# DAIDISIKE — Industrial Sensors & Machine Safety (daidisensor.com) > Foshan DAIDISIKE Optoelectronics Technology Co., Ltd. manufactures safety light curtains, measuring light curtains, press/press-brake protection, 2D TOF LiDAR, safety door locks, safety relays, proximity sensors, photoelectric sensors, laser switches, color mark sensors, fiber optic sensors and relay modules. Factory-direct from Foshan, Guangdong, China. OEM/ODM supported. Contact: WhatsApp +86 152 1890 9599. ## Product categories - [relay-module](https://www.daidisensor.com/products/relay-module/): 23 series — A1J0101 Economical Input Amplifier Module; B2J0101 Economical Power-up Delay Module; B2J0201 Economical Trigger Delay Module; B2J0302 Enhanced Single MODBUS-485 I/O Module; B2J0401 MODBUS Analog/Digital I/O Module. This directory groups ordinary automation modules, not interchangeable safety controllers. Start with the control task: timed switching, distributed I/O, protocol conversion, signal isolation or compact programmable logic. A connection to a PLC does not make a relay module a safety PLC. - [photoelectric-sensor](https://www.daidisensor.com/products/photoelectric-sensor/): 16 series — BGS-CX441 / BGS-CX442 Background Suppression Photoelectric Sensor; BGS-CX61 Focused-Beam Background Suppression Photoelectric Sensor; BX Series Long-range Background Suppression (BGS) Photoelectric Sensor; DD-301/401/302/402 Series Reflective Photoelectric Sensor (Wire-lead Type); DD-T21 / DD-T31 / DD-D21 Compact Self-Contained Photoelectric Sensor. A photoelectric sensor should first be selected by the optical path: **through-beam**, retro-reflective, diffuse-reflective, or background suppression. That choice decides whether the target must break a beam, return light to a receiver, or be separated from a background by distance. Housing, range and NPN/PNP output come after the sensing mode. - [color-mark-sensor](https://www.daidisensor.com/products/color-mark-sensor/): 5 series — CZ-V1 High-Precision Color Sensor; CZ-V21 RGB Digital Color Sensor (Amplifier-Separate Type); FS-S72 Color Mark Sensor (FS-S72 NPN / FS-S72P PNP); JNS-W70 / JNS-W500 Long-Range Color Mark Sensor; PZ-LX101 Color Mark Sensor. Detecting a registration mark against its background is not the same task as distinguishing several colours. Define the printed mark, background, surface finish, working distance and required control result before comparing sensor housings. Test the actual printed stock, not only a colour description. - [proximity-sensor](https://www.daidisensor.com/products/proximity-sensor/): 26 series — D6.5 Series Inductive Proximity Sensors (Ultra-Short 18mm / Y-Type / 35mm / 45mm); Economy Inductive Proximity Sensors M8/M12/M18/M30 (JNX/JNS Series); Economy M4/M5/M6 Inductive Proximity Switches (Export-Grade); High-Quality Threaded M4/M5/M6 Inductive Proximity Sensors; JD Series 3-Wire Connector-Type Inductive Proximity Sensors D6.5-M8 / D6.5-M12. Start with the target, not the thread size. An **inductive proximity sensor** detects metal without contact; a **capacitive proximity sensor** can also detect non-metal targets such as plastic, glass, powder or liquid when the application is validated. Then choose the mounting geometry, sensing distance and output that match the machine input. - [safety-relay](https://www.daidisensor.com/products/safety-relay/): 2 series — DA31 Emergency-Stop Safety Relay Module; DQSRN Safety Relay Module. A **safety relay module** evaluates a dual-channel signal from an emergency-stop device, safety light curtain, safety door interlock or two-hand control and uses forcibly guided contacts to interrupt hazardous machine functions. It is the evaluation stage between the field safety device and the machine contactors — not the sensor, PLC or contactor itself. - [safety-light-curtain](https://www.daidisensor.com/products/safety-light-curtain/): 17 series — DCE Automation Safety Light Curtain; DD / DDOF Single-Sided Area Light Curtain; DQA Long-distance Safety Light Curtain; DQB Ultra-thin (Side-emitting) Safety Light Curtain; DQBT Ultra-thin Optical-sync Safety Light Curtain. Compare seventeen light-curtain series by the exact configuration you need to order. Personnel-protection equipment must have documented detection capability, safety outputs and an applicable safety rating. This existing catalogue also contains the [DD / DDOF single-sided area sensors](/products/safety-light-curtain/dd-diffuse-reflection-area-light-curtain/): they are object-detection products, not personnel-protection devices, despite their position in this directory. - [slot-sensor](https://www.daidisensor.com/products/slot-sensor/): 5 series — DD-303N / DD-403N Wide-slot Photoelectric Sensor; DD-670 Series Slot Photoelectric Sensor (Pin/Plug-in Connector Type); DD-L25/45 Series Micro-slot (Micro U-shaped) Photoelectric Sensor; EE-SX67 Series Slot-type Photoelectric Sensor (Photomicrosensor); FS-KNS Slot Photoelectric Sensor (Plug-in Type). A slot sensor contains opposing optical elements in one body. Compare slot width, slot depth, target path, bracket access and connector orientation before choosing output logic. The nominal slot size is not a guarantee that every small or transparent target can be detected. - [laser-distance-sensor](https://www.daidisensor.com/products/laser-distance-sensor/): 3 series — DDA-Y & DDB-Y Industrial Laser Distance Sensor (Phase-Shift); DDK-F Long-range Laser Distance Sensor; DSK-CG Long-range Laser Distance Sensor. Select a laser distance sensor from the actual near and far working positions, the target surface and the controller signal. Range, measurement error, update rate and switching behaviour are separate requirements. Ask for the selected configuration rather than treating every interface listed for a family as simultaneously available. - [outdoor-security-sensor](https://www.daidisensor.com/products/outdoor-security-sensor/): 1 series — DDSK-J Outdoor Laser Beam Detector. An outdoor beam detector belongs to a perimeter alarm design, not a machine personnel-protection function. Selection must include line of sight, mounting stability, alarm interface, weather exposure and the response required by the security system. Nominal optical distance is not a guarantee for every outdoor condition. - [laser-switch-sensor](https://www.daidisensor.com/products/laser-switch-sensor/): 7 series — DDSK Laser Diffuse Reflective Sensor M12 / DK Laser Diffuse Reflective Sensor M18; DDSK Ultra-Miniature Laser Diffuse Reflective Sensor (M3/M4/M5/M6/M8); DS Laser Through-Beam Sensor M12/M18 (50m); DS Miniature Laser Through-Beam Sensor (M3/M4/M5/M6/M8); DS Right-Angle (90°) Laser Through-Beam Switch M4 / M6. Laser switches provide a switching result; they are not automatically displacement gauges or safety scanners. Choose one-sided diffuse detection or an opposed emitter/receiver arrangement according to target access, then compare spot size, working gap, housing and electrical output for the actual model. - [laser-displacement-sensor](https://www.daidisensor.com/products/laser-displacement-sensor/): 3 series — DK-G Series Laser Displacement Sensor; DDK-G Laser Displacement Sensor 30-250 mm; LK-F Series CMOS Laser Displacement Sensor. Laser displacement selection begins with the reference position, total movement and real target surface. A repeatability value is not automatically absolute accuracy, resolution or performance on another surface. Keep the selected model, sampling conditions and receiving controller in the same purchase specification. - [hot-metal-detector](https://www.daidisensor.com/products/hot-metal-detector/): 1 series — DK-SCZ-II Hot & Cold Metal Detector (Laser Distance Type). For a metal-processing line, state what must be detected and how the target passes the sensor. Target temperature, scale, glare, steam, dust, vibration and mounting distance are application inputs; a family name alone does not establish operation in every furnace or rolling-line condition. - [press-brake-protection](https://www.daidisensor.com/products/press-brake-protection/): 3 series — DKE-L3 Press Brake Laser Protection; DQS Press Photoelectric Safety Guard; DQV Double-sided Photoelectric Safety Protection Device - [lidar](https://www.daidisensor.com/products/lidar/): 10 series — DLD-100D Single-Line TOF Scanning LiDAR; DLD-50D 2D TOF LiDAR for Navigation & Mapping (50 m); DLD-50G 2D Single-line LiDAR (Diffuse-remission Measuring Type); DLD05A3 2D TOF Obstacle-avoidance LiDAR (5 m); DLD20A5-5N / DLD20A5-5P 2D TOF Obstacle-avoidance LiDAR (20 m). Separate a safety protective field from ordinary obstacle detection and navigation data before comparing distance. The catalogue includes safety scanning, configurable discrete-output devices and measurement/navigation scanners. A long maximum range or a software stop zone does not turn a measuring scanner into a safety device. - [measuring-light-curtain](https://www.daidisensor.com/products/measuring-light-curtain/): 3 series — DQL Measuring Light Curtain (Analog/RS485); DQLV Vehicle Separation Light Curtain; DQM Measuring Light Curtain (Switching Output) - [safety-door-lock](https://www.daidisensor.com/products/safety-door-lock/): 9 series — DX-C1 Magnetic Coded Safety Switch; DX-D2 & DX-D3 Safety Door Switch; DX-D6 Guard Locking Safety-Door Switch; DX-K Series Safety Door Lock Operation Keys; DX-R1 Non-contact Safety Switch (RFID Coded). A **safety interlock switch** either monitors whether a machine guard is closed, or monitors and physically locks it. Monitoring without locking requires the hazard to stop before a person can reach it, as verified by the machine risk assessment. Use guard locking when the assessment requires the door to remain closed until a persistent hazard has ended and release is permitted. - [fiber-optic-sensor](https://www.daidisensor.com/products/fiber-optic-sensor/): 3 series — Fiber Amplifier (Digital Fiber Optic Sensor Amplifier); Fiber Optic Sensor Heads (Fiber Units); Matrix (Array) Fiber Optic Heads. A fibre-optic sensing package may require a separate amplifier and optical head. Compare the task, available mounting space, fibre routing and receiving controller as one assembly. A fibre head alone is not a complete electrical sensor, and a head/amplifier combination must be confirmed before ordering. - [safety-edge](https://www.daidisensor.com/products/safety-edge/): 2 series — JB-PSE Series Pressure-Sensitive Safety Edge; JB Series Safety Edge (Economy Line). A pressure-sensitive edge detects contact along a moving edge. Its profile, mounting rail, end treatment, cable exit and evaluation interface belong to the selected system. It is not interchangeable with a floor mat or non-contact protective field. - [contact-displacement-sensor](https://www.daidisensor.com/products/contact-displacement-sensor/): 1 series — JNS-Q Contact Displacement Grating Sensor. A contact displacement probe measures by touching the workpiece. Select the usable stroke, tip arrangement, mounting, return or actuation method and compatible readout before comparing a single precision figure. Family options must not be silently assigned to every individual model. - [safety-mat](https://www.daidisensor.com/products/safety-mat/): 1 series — JT14 Safety Mat (Economical). Pressure-sensitive mat selection includes the floor area, access paths, joints, edge profiles, cable exits and evaluation system. A mat alone does not validate the machine stop function. Confirm the complete mat/controller combination and its applicable documentation for personnel protection. ## What we do - Manufacture and supply the sensor and machine-safety product lines listed above, factory-direct from Foshan, Guangdong, China. - OEM / ODM: custom housings, cable lengths, connectors, labelling and model codes on our existing platforms. - Supply the operating instructions, wiring information and technical data needed to design our products into a machine. - Send certification documentation on request, for the exact model code you intend to use. ## Capability boundaries — what we do NOT do - We do not provide machine risk assessments, safety-distance calculations or CE marking for your machine. Those are the machine builder's or integrator's responsibility under ISO 12100 / ISO 13849-1 / ISO 13855. We publish the device parameters those calculations need (response time, extension distance ZR, tolerance zone, object resolution) and worked examples that illustrate the formulae only. - We do not claim third-party certification we cannot document. Where a certificate exists we send it on request; where a figure is not published in the product's operating instructions we say so rather than estimate it. - We do not publish PFHd, MTTFd or TM figures for every product. Where they are not in the manual, ask and we will confirm with the factory before you design the product in. - Our LiDAR products fall into two distinct groups and they are not interchangeable: the ST27 series is presented as safety-rated electro-sensitive protective equipment (Type 3 / SIL 2 / PL d, OSSD outputs; verify the exact configuration and applicable documentation). DLD and SDLD products use ordinary navigation or measurement interfaces, which vary by model; they must not be treated as protective devices for a machine safety function. Check the exact model for switching, Ethernet or other interface requirements. - Scanner detection capability and protective-field limits are model- and configuration-specific. Do not generalise one scanner's object size to the category. For a light curtain, beam pitch is not the same as minimum detectable object; verify its documented detection capability and applicable safety scope. - DQSRN supports manual or automatic reset according to its confirmed current instructions; follow the selected version's circuit. EDM is not claimed without explicit evidence. DA31 requires its own current documentation. Ordinary programmable relay/I/O modules are not safety PLCs. - We are a manufacturer, not a systems integrator. We do not install, commission or validate safeguarding on site. ## Key pages - [All products](https://www.daidisensor.com/products/) - [About / factory / certificates](https://www.daidisensor.com/about/) - [Contact & quotes](https://www.daidisensor.com/contact/) - [Industry news & engineering insights](https://www.daidisensor.com/news/) ## Latest engineering articles - [Embodied AI Robots Enter Factories in 2026: How Light Curtains, Guard Locks, Safety Laser Scanners and Displacement Sensors Divide the Work](https://www.daidisensor.com/news/embodied-ai-robots-factory-sensor-role-selection/): A 2026 engineering guide to choosing light curtains, guard locks, safety laser scanners and displacement sensors for embodied AI robot cells. - [Press Brake and Punch Press Light Curtain Guarding: What Actually Fails on the Factory Floor](https://www.daidisensor.com/news/press-brake-punch-press-light-curtain-guarding/): Press and press-brake guard selection: five integration risks, detection-capability checks, limited distance arithmetic, and a qualified-verification checklist. ## Selection guides - [How to Choose a 2D LiDAR Scanner](https://www.daidisensor.com/guides/how-to-choose-a-lidar-scanner/): How to choose a 2D LiDAR scanner: discrete outputs vs point-cloud data, range at low reflectivity, field of view, zone sets, and IP ratings for AGVs. - [How to Choose an Inductive or Capacitive Proximity Sensor](https://www.daidisensor.com/guides/how-to-choose-a-proximity-sensor/): How to choose an inductive or capacitive proximity sensor: target material, flush vs non-flush mounting, sensing distance, wiring, and NPN/PNP outputs. - [How to Choose a Safety Door Switch / Interlock](https://www.daidisensor.com/guides/how-to-choose-a-safety-door-lock/): How to choose a safety door switch or guard-locking interlock: locking type, holding force, non-contact coded switches, ISO 14119 coding, and wiring. - [How to Choose a Safety Light Curtain](https://www.daidisensor.com/guides/how-to-choose-a-safety-light-curtain/): Step-by-step guide to choosing a safety light curtain: resolution, protective height, range, safety distance, NPN/PNP outputs, and IP ratings explained. - [NPN vs PNP Sensor Outputs Explained](https://www.daidisensor.com/guides/npn-vs-pnp-outputs-explained/): NPN vs PNP sensor outputs explained: sinking vs sourcing, PLC input matching, NO vs NC logic, wiring colors, and how to pick the right output type. - [Type 2 vs Type 4 Safety Light Curtains](https://www.daidisensor.com/guides/type-2-vs-type-4-safety-light-curtains/): Compare Type 2 and Type 4 light-curtain claims before ordering: fault behaviour, exact output version, detection capability, certificate scope and required evidence. # Product index (all series) ## relay-module Category URL: https://www.daidisensor.com/products/relay-module/ ### Select Timing, I/O or Programmable Control Before the Order Code This directory groups ordinary automation modules, not interchangeable safety controllers. Start with the control task: timed switching, distributed I/O, protocol conversion, signal isolation or compact programmable logic. A connection to a PLC does not make a relay module a safety PLC. ### Compare the Configuration Paths Required task | Existing product page | What to confirm Power-on or externally triggered timing | [B2J0101 power-up timing](/products/relay-module/b2j0101-economical-power-up-delay-module/) | Compare trigger source and timing sequence with the selected B2J/E4J model. Multifunction timing | [E4J0101 timing configurations](/products/relay-module/e4j0101-easy-multifunctional-trigger-delay-module/) | Confirm the exact input, output, timing range and configuration method from its table. Remote I/O configuration | [B2J0401 I/O ordering options](/products/relay-module/b2j0401-relay-module/) | Count digital/analog inputs and outputs separately; B2J0401 and B2J0405 are different ordering codes. Ethernet to RS485 communication | [B2J0701 gateway options](/products/relay-module/b2j0701-ethernet-rs485-modbus-gateway-module/) | Confirm protocol roles, connected equipment, register access and network arrangement. Compact programmable sequencing | [E4J0206 programmable-control configuration](/products/relay-module/d4g0206-relay-module/) | The existing page address is retained; use the confirmed E4J0206 ordering name and verify the actual I/O version. ### Specify I/O and Mechanical Options as Separate Line Items Purchase input | Information to provide I/O schedule | List each input signal and each output load, including voltage, current and isolation requirements. D3J-02XX covers 2–14 outputs; select the exact channel-count model. Timing or program behaviour | Provide the required sequence, trigger conditions and restart behaviour; do not assume every timer supports every cyclic mode. Housing and installation | For B2J/E4J, DIN-rail mounting, bare-board supply and enclosure choices are options. State which arrangement the quotation should include. When the job is a protective stop, use the [DA31 and DQSRN safety relay directory](/products/safety-relay/) and verify the complete safety circuit. Ordinary programmable process modules must not replace that function. Send the application details and required configuration through the [inquiry form](/contact/) so that the quotation identifies the selected equipment and options. ### A1J0101 Economical Input Amplifier Module URL: https://www.daidisensor.com/products/relay-module/a1j0101-economical-input-amplifier-module/ A1J0101 optocoupler-isolated input amplifier module: 1000V input isolation, 250V AC/10A relay output, 5-24V DC supply, selectable high/low-level trigger. - Input isolation is rated DC 1000V for 60s (type test); working input isolating voltage is less than 250V. - The relay output switches DC 30V or AC 0-220V at 8A under normal conditions, with an absolute maximum of AC 250V, 10A on both the NO and NC contacts. - Supply current is less than 50mA, typically 40mA with the relay energized, from a 5V, 9V, 12V, 18V or 24V DC supply. - Relay mechanical life exceeds 100,000 operations (more than 10,000 under heavy load). ### B2J0101 Economical Power-up Delay Module URL: https://www.daidisensor.com/products/relay-module/b2j0101-economical-power-up-delay-module/ B2J0101 power-up delay relay module: 2-30s adjustable delay via potentiometer, 5-24V DC supply, single relay output up to 250V AC/10A, no trigger input. - B2J0101's power-up delay is adjustable from 2 to 30 seconds via an on-board potentiometer, with no external trigger input — the countdown starts the instant power is applied. - B2J0101 can be supplied from 5V, 9V, 12V, 18V or 24V DC, with a supply current below 50mA (typical 40mA when the relay is energized). - B2J0101's single relay output is rated up to 250V AC / 10A as an absolute maximum, with a normal operating output stress of AC 0-220V or DC 30V at 8A. - B2J0101's output isolation voltage is type-tested to DC 1000V / 60s (relay type), with continuous operating isolation below 250V. ### B2J0201 Economical Trigger Delay Module URL: https://www.daidisensor.com/products/relay-module/b2j0201-economical-trigger-delay-module/ B2J0201 economical trigger delay relay module: 5-24V DC supply, jumper-selectable high/low-level trigger, 2-30s adjustable delay, 250V AC/10A relay output. - The B2J0201 begins its delay only after an external trigger signal or button press is applied; the relay does not start counting down at power-up. - Delay time is adjustable from 2 to 30 seconds via an on-board NE555-based potentiometer circuit, with no programming required. - Trigger polarity is jumper-selectable: high-level trigger fires on a voltage above 2V at the trigger terminal, low-level trigger fires when the terminal is shorted to ground. - The default M31 configuration is a 12V DC supply with a single-channel relay output rated AC 250V / 10A absolute maximum (NO/NC), and relay mechanical life exceeds 100,000 operations. ### B2J0302 Enhanced Single MODBUS-485 I/O Module URL: https://www.daidisensor.com/products/relay-module/b2j0302-economical-single-modbus-485-i-o-module/ B2J0302 enhanced MODBUS-RTU/RS-485 I/O module: 1 digital + 2 analog inputs (0-35V/0-5V), relay output to 250V AC/10A or transistor to 48V DC, AT commands, PWM. Replaces B2J0301. - B2J0302 is the enhanced single-channel MODBUS-RTU RS-485 I/O module: 1 digital input, 2 analog inputs, 1 relay or open-drain transistor output. - It is the direct successor to the discontinued B2J0301 — same wiring, same board size, same MODBUS registers for input and output, with added functions. - Relay output: NO and NC contacts rated 30 V DC or 0-220 V AC at 8 A working (250 V AC / 10 A absolute maximum); mechanical life over 100,000 operations. - Transistor variant: open-drain output 12-48 V DC at 8 A working with built-in 10 A freewheel diode, plus PWM output about 337 Hz to 86.4 kHz with 8-bit duty resolution. ### B2J0401 MODBUS Analog/Digital I/O Module URL: https://www.daidisensor.com/products/relay-module/b2j0401-relay-module/ B2J0401 MODBUS-RTU/RS-485 I/O module: 4 digital/analog dual-use inputs, 2 MOSFET PWM/PTO outputs, selectable supply/output variants and USB configuration. - 4 digital/analog dual-use inputs (DIN0-3 / AIN0-3) on the same terminals: 16-bit analog register with LSB = 1 mV and typical 3% full-scale accuracy, or digital input with a threshold of about 3 V. - Per-channel debounce filter configurable 1-65535 ms in 1 ms steps, plus rising-edge pulse counting that rolls over at 65535 at frequencies up to 5 Hz. - 2 open-drain MOSFET outputs (DOUT0/DOUT1) with direct drive, on-delay (5 trigger modes), standard PWM, standard PTO (channels 0/1) and fast PWM (channel 0). - Emergency brake set by BRKCFG blocks the outputs immediately, latches BRKFLG = "BK" until cleared over the communication port, and takes priority over forced output. ### B2J0601 Economical Intelligent Trigger Delay Module URL: https://www.daidisensor.com/products/relay-module/b2j0601-economical-intelligent-trigger-delay-module/ B2J0601 economical intelligent delay relay module: 26 delay modes, 0-255 unit second/minute/hour timing, 30 ppm accuracy, and 0-30V voltage detection. - 26 delay modes in one module: 3 time units (second/minute/hour) x 8 trigger/action templates = 24 modes, plus 2 edge-triggered self-locking modes. - Delay time is set from 0 to 255 units with a single button, so one board covers a 2-second flashing interval and a 200-hour soak cycle. - Long-term delay accuracy reaches 30 ppm, with no drift from temperature, humidity or supply voltage across the -20 to 60 C operating range. - Supply versions of 5V, 9V, 12V and 24V DC (default M31 = 12V relay output) draw less than 50 mA, typically 40 mA with the relay energised. ### B2J0701 Ethernet to RS-485 MODBUS-TCP Gateway Module URL: https://www.daidisensor.com/products/relay-module/b2j0701-ethernet-rs485-modbus-gateway-module/ B2J0701 Ethernet to RS-485 gateway: MODBUS-TCP to RTU conversion, transparent mode, TCP server/client, USB config, 5-24V DC. Puts your RS-485 modules on the network. - B2J0701 is an economical Ethernet (10Base-T) to RS-485 gateway: MODBUS-TCP to MODBUS-RTU conversion plus transparent serial tunnelling in one module. - Works as a TCP server for classic LAN topologies, or as a TCP client that connects outward to a host or cloud server — the right choice behind NAT firewalls on wide-area installations. - Gateway mode is request-response managed with a frame-timeout mechanism, so an unresponsive RS-485 slave cannot stall the whole bus. - Transparent mode tunnels arbitrary serial data with 4 KiB receive and transmit buffers and a basic transport-encryption option — legacy serial protocols keep working over the network. ### D3J0104 Modbus URL: https://www.daidisensor.com/products/relay-module/d3j0104-modbus/ D3J0104 Modbus-RTU/RS-485 digital input module: 4 isolated inputs, 2 analog inputs, 11-28V DC supply, edge counting and adjustable filtering per channel. - 4 fully isolated digital inputs, plus 2 analog input channels and 1 x 5V/100mA sensor supply, on a 54 x 88 x 59mm board with 5.08mm terminal pitch. - Default communication is 9600bps, 8 data bits, even parity, 1 stop bit at slave address 0x02; the address range is 1-247 and the baud rate is selectable up to 115200bps. - Supply voltage is DC 11-28V, drawing typically 40mA and under 1500mA, with ripple tolerance under 1Vp-p. - Each channel has an independent input filter adjustable 1-65535ms and a rising-edge counter that runs up to 5Hz and rolls over at 65535. ### D3J0108 Modbus URL: https://www.daidisensor.com/products/relay-module/d3j0108-modbus/ D3J0108 (D3J01 series) is an 8-channel fully isolated Modbus-RTU/RS-485 digital input module with DC 11-28V supply and 2kV EFT immunity for control cabinets. - 8 fully isolated digital inputs plus 2 auxiliary analog input channels (1mV per bit, approx. 10-bit, typ. 3% accuracy) and a 5V/100mA sensor power output. - EFT immunity of 2kV/5kHz/2min at Criterion A - double the 1kV required by IEC61000-6-2-2016 for industrial environments. - Default Modbus-RTU communication: 9600 bps, 8 data bits, even parity, 1 stop bit, slave address 0x02, with an address range of 1-247 and baud rates up to 115200 bps. - Inputs accept DC 0-30V with an approximately 3V threshold; input response time is typically 20ms and serial reply time is at most 25ms. ### D3J0116 Modbus URL: https://www.daidisensor.com/products/relay-module/d3j0116-modbus/ D3J0116 (D3J01 series) is a 16-channel fully isolated Modbus-RTU/RS-485 digital input module, DC 11-28V supply, 2 analog inputs, 2kV EFT immunity, for panels. - 16 fully isolated digital inputs on one Modbus node, plus 2 bonus analog input channels and a 5V/100mA sensor power output. - Default Modbus-RTU communication is 9600 bps, 8 data bits, even parity, 1 stop bit at slave address 0x02; the address range is 1-247 and the baud rate is selectable up to 115200 bps. - EFT immunity is 2kV/5kHz, twice the 1kV level the IEC61000-6-2-2016 industrial standard asks for; ESD of 4kV to all terminals leaves operation normal (Criterion A). - Per-channel rising-edge counting up to a 5Hz pulse rate (rolls over at 65535) and per-channel input filtering adjustable from 1 to 65535ms, savable through power loss. ### D3J0128 Modbus URL: https://www.daidisensor.com/products/relay-module/d3j0128-modbus/ D3J0128 is a 28-channel fully isolated Modbus-RTU/RS-485 digital input module with DC 11-28V supply and 2kV EFT immunity for industrial control panels. - D3J0128 provides 28 fully isolated digital inputs plus 2 analog input channels and 1 x 5V/100mA sensor power output; it is a pure-input module with no relay or transistor outputs, measuring 158 x 88 x 59mm (tolerance +/-5%) with 5.08mm terminal pitch, one green power LED and one yellow LED per input channel. - All 28 inputs sit in the discrete input block from address 0x0000 under a single slave address, so one function code 0x02 poll returns every channel state, with a serial reply time of up to 25ms and typical input response of 20ms. - Supply voltage is DC 11-28V (absolute maximum DC 28V) with supply current under 1500mA, ripple under 1Vp-p, and a DC 250V / 3000mA slow-blow fuse on board; the module operates from -20 to 60C and stores from -40 to 85C. - Default communication is 9600bps, 8 data bits, even parity, 1 stop bit at slave address 0x02 (fixed at 0x01 in USB mode); baud rate is configurable from 300 to 115200bps and slave address from 1-247. ### D3J0202 Modbus URL: https://www.daidisensor.com/products/relay-module/d3j0202-modbus/ D3J0202 Modbus-RTU/RS-485 digital output module: 2 isolated relay or transistor outputs, 8A switching, DC 11-28V supply, optional PWM/PTO on existing DO0/DO1. - The D3J0202 provides 2 fully isolated digital output channels, each with NC / COM / NO terminals, orderable as relay type (DC 30V or AC 0-220V, 8A) or open-drain transistor type (DC 12-48V, 8A, with a built-in 10A freewheeling diode); product ID is 0x3202 and the default shipped order code is D3J0202M111 (all-relay output, pulse unavailable, no wireless). - It runs on a DC 11-28V supply at 40mA typical (under 1500mA maximum, ripple below 1Vp-p) and operates from -20 to 60 degrees C, with storage from -40 to 85 degrees C. - Communication is Modbus-RTU over RS-485, defaulting to 9600bps / 8 data bits / even parity / 1 stop bit, with 300-115200bps and slave addresses 1-247 (0x01-0xF7) selectable; the 2 outputs occupy coils 0x0000-0x0007 and respond to function codes 0x01, 0x05 and 0x0F. - Relay mechanical life exceeds 100,000 operations, and over 10,000 operations under heavy load. ### D3J0204 Modbus URL: https://www.daidisensor.com/products/relay-module/d3j0204-modbus/ D3J0204 4-channel Modbus-RTU/RS-485 output module: relay or MOSFET output, 8A per channel, optional PWM/PTO on existing DO0/DO1, DC 11-28V, 9600-115200bps. - 4 fully isolated digital output channels in a 72 x 88 x 59 mm body, each with its own NC/COM/NO screw terminals on a 5.08 mm pitch. - Relay-type contacts switch AC 0-220 V or DC 30 V at 8 A with a mechanical life over 100,000 cycles (over 10,000 cycles under heavy load); open-drain MOSFET-type outputs are rated DC 12-48 V, 8 A and carry a built-in 10 A flyback diode. - Up to 2 of the 4 channels (DO0/DO1) can be ordered as high-speed transistors for standard PWM, standard PTO or fast-PWM pulse output, in addition to their on/off function. - Standard MODBUS-RTU slave: default 9600 bps / 8 data bits / even parity / 1 stop bit at address 0x02, with baud rates 300-115200 bps, addresses 1-247 (0x01-0xF7) and product ID 0x3204. ### D3J0208 Modbus URL: https://www.daidisensor.com/products/relay-module/d3j0208-modbus/ D3J0208 is an 8-channel isolated Modbus-RTU/RS-485 digital output module with relay or transistor outputs, DC 11-28V supply, 8A, optional PWM/PTO on existing DO0/DO1. - 8 fully isolated digital outputs with NC/COM/NO screw terminals on each channel (24 output terminals, 5.08mm pitch); up to two of these existing channels (DO0/DO1) can be ordered for high-speed PWM/PTO. Pulse mode does not add outputs. - Relay outputs are rated DC 30V or AC 0-220V at 8A with a mechanical life of over 100,000 operations (over 10,000 under heavy load); transistor (open-drain) outputs are rated DC 12-48V at 8A with a built-in 10A flyback diode for inductive DC loads. - Default Modbus-RTU communication is 9600 bps, 8 data bits, even parity, 1 stop bit at slave address 0x02, selectable across 300-115200 bps and addresses 1-247; the 8-channel type maps its outputs to coils 0x0000-0x001F. - Ten Modbus function codes are supported, including 0x01 read coils, 0x05 write single coil, 0x0F write multiple coils, 0x03/0x06/0x10 holding registers, 0x04 read input registers and 0x11 report device ID; product ID is 0x3208. ### D3J0214 Modbus URL: https://www.daidisensor.com/products/relay-module/d3j0214-modbus/ D3J0214 is a 14-channel Modbus-RTU RS-485 isolated digital output module with relay or transistor outputs, 8A switching, and optional PWM/PTO on existing DO0/DO1. - 14 fully isolated digital output channels in a single 158 x 88 x 59 mm module, terminal pitch 5.08 mm. - Relay outputs switch DC 30V or AC 0-220V at 8A, with a mechanical life over 100,000 cycles (10,000+ under heavy load). - Transistor outputs are open-drain at DC 12-48V / 8A, with a built-in 10A flyback diode for direct inductive loads. - The 14 channels occupy all 56 Modbus coils from 0x0000 to 0x0037; product ID and address code is 0x3214, default slave address 0x02. ### D3J0302 Modbus URL: https://www.daidisensor.com/products/relay-module/d3j0302-modbus/ D3J0302 (D3J03 series) is a 2-input/1-output Modbus-RTU/RS-485 I/O module with relay or transistor output, DC 11-28V supply, and 2kV EFT immunity. - One 54 x 88 x 59mm module with 8 screw terminals at 5.08mm pitch carries 2 fully isolated digital inputs, 1 digital output, 2 analog inputs, up to 2 high-speed pulse outputs and a 5V/100mA sensor supply. - Supply is DC 11-28V at under 1500mA with ripple below 1Vp-p; operating range is -20 to 60C and storage -40 to 85C. - Default Modbus-RTU communication is 9600 bps, 8 data bits, even parity, 1 stop bit at slave address 0x02; baud rate is selectable from 300 to 115200 bps and the address range is 1-247. - Relay output is rated DC 30V or AC 0-220V at 8A; the transistor option is open-drain, rated DC 12-48V at 8A, with a built-in 10A flyback diode that can drive 10A inductive loads directly. ### D3J0304 Modbus URL: https://www.daidisensor.com/products/relay-module/d3j0304-modbus/ D3J0304 Modbus-RTU/RS-485 digital I/O module: 4 isolated inputs, 2 relay/transistor outputs, 11-28V DC supply, local input-linked output and emergency brake. - 4 fully isolated digital inputs (threshold approx. 3V, input stress DC 0-30V) and 2 digital outputs on one board, plus 2 analog inputs, up to 2 PWM/PTO pulse outputs and a 5V/100mA sensor supply. - Relay outputs are rated DC 30V or AC 0-220V at 8A with mechanical life over 100,000 cycles; the optional FET version is open-drain, DC 12-48V, with a built-in 10A flyback diode for inductive loads. - Default communication is Modbus-RTU at 9600bps, 8 data bits, even parity, 1 stop bit; baud rates 300-115200bps, slave address range 1-247, default address 0x02, product identification code 0x3304. - Supply voltage is DC 11-28V at under 1500mA, with ripple under 1Vp-p; operating temperature is -20 to 60C. ### D3J0308 Modbus URL: https://www.daidisensor.com/products/relay-module/d3j0308-modbus/ D3J0308 Modbus-RTU/RS-485 I/O module: 8 isolated inputs, 4 relay/transistor outputs at 8A, DC 11-28V supply, with local interlock and emergency braking. - 8 fully isolated digital inputs and 4 fully isolated digital outputs (relay or transistor type, selectable at order time) on one module, plus 2 analog inputs, up to 2 PWM/PTO pulse channels and a 5V/100mA sensor supply. - Relay output switches DC 30V or AC 0-220V at 8A; transistor output is open-drain at DC 12-48V / 8A with a built-in 10A freewheeling diode for direct inductive-load drive. - Supply voltage DC 11-28V at under 1500mA; RS-485 communication, inputs and outputs are each electrically isolated from the internal logic (isolation voltage under 250V, normal condition). - Typical input/output response time 20ms and maximum serial command reply time 25ms; each input has a 65535-count rising-edge counter and an adjustable debounce filter retained through power loss. ### D3J0312 Modbus URL: https://www.daidisensor.com/products/relay-module/d3j0312-modbus/ D3J0312 Modbus-RTU/RS-485 I/O module: 12 isolated inputs, 8 relay/transistor outputs at 8A, DC 11-28V supply, plus analog input and PWM/PTO pulse outputs. - 12 fully isolated digital inputs and 8 fully isolated digital outputs (relay or transistor type, selectable at order time) on one module - the highest channel count in the D3J03 series. - Relay-type outputs switch DC 30V or AC 0-220V at 8A; transistor-type outputs are open-drain, DC 12-48V at 8A, with a built-in 10A freewheeling diode. - Default Modbus-RTU communication at 9600bps, 8 data bits, even parity, 1 stop bit; baud rate selectable 300-115200bps; slave address range 1-247 (0x01-0xF7); product ID 0x3312. - Typical I/O response time 20ms and maximum serial reply time 25ms; relay mechanical life exceeds 100,000 operations (over 10,000 under heavy load). ### D4G0206 Relay Module URL: https://www.daidisensor.com/products/relay-module/d4g0206-relay-module/ E4J0206 micro PLC module: schematic programming replaces ladder logic, with 6 digital/analog inputs and 4 relay or transistor outputs rated up to 8A. - 6 input channels accept 0-35V DC and each one takes either a digital or an analog signal; the inputs are not isolated from the supply, so field devices must share the module's 0V rail. - 4 independent digital outputs. The relay version provides potential-free NO-COM-NC changeover contacts; the transistor version uses a different DC sinking output arrangement. Apply the selected version's load, voltage and switching-duty ratings rather than treating both versions as relay contacts. - Power input accepts 11-24V DC (absolute max 28V) with reverse-polarity protection; consumption is 250mA maximum running and 35mA maximum standby. - Tested to 1000V DC isolated output on the relay side; the inputs are non-isolated from the supply; creepage is 6mm minimum and clearance 2mm minimum from the relay terminals to the logic side at pollution degree 3. ### E4J0101 Easy Multifunctional Trigger Delay Module URL: https://www.daidisensor.com/products/relay-module/e4j0101-easy-multifunctional-trigger-delay-module/ E4J0101 multifunctional trigger delay relay module: about 100 delay templates, ~1,000 delay modes, 1.5% factory accuracy (0.1% after calibration). - About 100 basic delay templates in five groups (switching 5, delay-then-break 40, delay-make-then-break 34, cyclic delay 17, counting delay 8) combine with input/output polarity inversion for roughly 1,000 distinct delay modes. - Delay times A and C are each set as 0-999 multiplied by a selectable unit of 10 ms, 100 ms, 1 s, 10 s, 1 min, 10 min, 1 h or 10 h; loop count L is 0-9999, where 0 means unlimited. - Factory delay accuracy is 1.5% across the full -20 to 60 C operating range, tightened to 0.1% (0.05% with fine calibration) after USB PC calibration over a trim range of about +/-2%. - Measured noise immunity is 2000 V EFT and 4000 V ESD, twice the 1 kV EFT required by IEC61000-6-2; the digital trigger input is optocoupler-isolated at a measured 1500 V DC. ### E4J0102 Easy Multifunctional Clock-Trigger Delay Module URL: https://www.daidisensor.com/products/relay-module/e4j0102-easy-multifunctional-clock-trigger-delay-module/ E4J0102 clock-trigger delay module: 0-30V voltage-threshold trigger, 0.01V resolution, optional RTC with 8 trigger points, ~1,000 delay modes, 5-24V DC. - The E4J0102's differential analog voltage input reads 0-30V per terminal and is non-polarized, with a threshold-setting resolution of 0.01V over a 0-39.99V range and analog-to-digital conversion accuracy of about 0.1V. - About 100 base delay templates combine with input/output polarity inversion into roughly 1,000 delay modes across five groups; delay times A and C are each adjustable 0-999 in eight time-unit steps from 10ms to 10h, with a cycle count of 0-9999. - Factory delay accuracy is about 1% (2% worst case) and can be calibrated via PC software to within 0.05%, using a calibration value of 0-100 that shifts timing by about 0.05% per step over a +/-2% range. - Selected versions include a battery-backed real-time clock with up to 8 calendar trigger points and an optional buzzer; each clock trigger produces about a 500ms trigger pulse, and calibrated real-world clock drift is 0.5 s/day typical and 2 s/day maximum. ### E4J0103 Easy Multifunctional Dual-Channel Trigger Delay Module URL: https://www.daidisensor.com/products/relay-module/e4j0103-easy-multifunctional-dual-channel-trigger-delay-module/ E4J0103 dual-channel trigger delay module: 3 optocoupler inputs, 2 relay/transistor outputs, ~1000 delay modes, four linkage types, 0.01% accuracy. - Two relay or transistor output channels that can be linked through four categories - simultaneous, sequential, alternating and mutual-follow (same / interlock / mutual-block) - selected by a single digit of the F--0 menu. - About 100 independent delay templates per channel across five groups, combined with input and output polarity reversal for about 1000 delay modes in total. - Delay times A and C are set 0-999 in units of 10 ms, 100 ms, 1 s, 10 s, 1 min, 10 min, 1 h or 10 h, with a cycle count L of 0-9999 (0 = unlimited). - Factory-default delay accuracy of 0.01% (one part in ten thousand) across the full -20 to 60 C operating range. ## photoelectric-sensor Category URL: https://www.daidisensor.com/products/photoelectric-sensor/ ### Choose a Photoelectric Sensor by Sensing Mode A photoelectric sensor should first be selected by the optical path: **through-beam**, retro-reflective, diffuse-reflective, or background suppression. That choice decides whether the target must break a beam, return light to a receiver, or be separated from a background by distance. Housing, range and NPN/PNP output come after the sensing mode. The sixteen series below range from M3–M18 threaded barrels and ultra-thin bodies to square relay-output sensors, strip-beam detectors and focused background-suppression models. The map identifies the correct family before you compare part numbers. Figure context: Four optical paths: select the mode by the target and mounting access, then choose range and output. ### Through-Beam, Retro-Reflective, Diffuse or Background Suppression Through-beam uses a separate emitter and receiver. It is the strongest starting point for mixed target colours and long spans because detection occurs when the target interrupts the beam. Retro-reflective places the emitter and receiver on one side and a reflector on the other. Diffuse-reflective works from one side with no reflector, using light returned by the target. Background suppression also works from one side but is designed to separate the target from objects beyond a set distance. Background suppression is a distance-selective optical method; it is not automatically time-of-flight. The BGS-CX and BX pages use only their published BGS descriptions and do not claim ToF. Mode | Hardware layout | Best starting point | Watch for Through-beam | emitter and receiver opposite | long span and mixed surfaces | two-sided mounting and alignment Retro-reflective | sensor one side, reflector opposite | one powered side with a clear reflector location | reflective targets may need application testing Diffuse-reflective | single sensor, target returns light | simple one-sided presence detection | colour and surface can change usable range Background suppression | single sensor, distance-selective optics | target in front of a nearby background | setting range and black/white differential ### M12 and M18 Through-Beam Photoelectric Sensors The [H-M through-beam family](/products/photoelectric-sensor/h-m-series-m12-m18-through-beam-photoelectric-sensor/) is the main M12/M18 opposed-mode range in this catalogue: M12 pairs at 2 m or 5 m, and M18 pairs at 5 m or 15 m, each offered in NPN or PNP and N.O. or complementary N.O.+N.C. output variants. It is the first series to compare for conveyor cross-belt detection, chute monitoring or a wide portal where target colour should not decide the result. For an ultra-thin housing and shorter span, compare the [DX-15/30/50/100 series](/products/photoelectric-sensor/dx-15-30-series-ultra-thin-self-contained-photoelectric-sensor/). For a square housing with internal relay or transistor choices, compare [E3JK](/products/photoelectric-sensor/e3jk-square-photoelectric-sensor/). Figure context: The receiver changes state when an object blocks the emitter beam; target colour is not the measurement. ### Diffuse-Reflective and Background-Suppression Selection Use compact diffuse models when one-sided mounting and straightforward presence detection matter: the [H-series M3–M6](/products/photoelectric-sensor/h-series-micro-diffuse-photoelectric-sensor/), [H08/R12 M8–M12](/products/photoelectric-sensor/h08-r12-series-micro-diffuse-reflective-photoelectric-sensor/), [JNS18/JNK18 M18](/products/photoelectric-sensor/jns18-and-jnk18-series-m18-diffuse-photoelectric-sensor/) and [QF-35 M8](/products/photoelectric-sensor/qf-35-m8-diffuse-reflective-photoelectric-sensor/) cover different footprints and ranges. Use BGS where a nearby machine wall or conveyor structure must be ignored. Compare the [BGS-CX61 focused-beam option](/products/photoelectric-sensor/bgs-cx61-focused-beam-background-suppression-photoelectric-sensor/), [BGS-CX441/CX442 adjustable families](/products/photoelectric-sensor/bgs-cx441-bgs-cx442-background-suppression-photoelectric-sensor/) and [BX long-range BGS family](/products/photoelectric-sensor/bx-series-long-range-background-suppression-photoelectric-sensor/) using their own setting ranges and target conditions. BGS does not by itself establish a ToF measurement principle. ### Photoelectric Sensor Output and Housing Checklist After the optical mode is fixed, match NPN or PNP to the PLC input and choose N.O., N.C. or complementary logic by the control sequence. Use the [NPN vs PNP guide](/guides/npn-vs-pnp-outputs-explained/) for the current path. Then check the real installation limits: supply voltage, response time, IP rating, minimum target, available mounting faces and cable replacement method. These are general-purpose detection sensors. They are not personnel-protection devices. For machine access safety, use the [safety light curtain range](/products/safety-light-curtain/) or [safety door switches](/products/safety-door-lock/) selected from the machine risk assessment. Send the target material, target size, sensing gap, background distance and PLC input type via the [inquiry form](/contact/) for a mode-first recommendation. ### Prepare a Target-and-Background Sample Check For a comparable photoelectric-sensor quote, provide a photo or sample of the darkest, glossiest or partially transparent target, the smallest feature, working distance and background position. Ask for the proposed model and test conditions to be recorded together; a catalogue range measured on one reference target does not prove performance on every surface. Purchase question | Where to compare Can both sides be mounted and cabled? | [H-M emitter/receiver pairs](/products/photoelectric-sensor/h-m-series-m12-m18-through-beam-photoelectric-sensor/) Must the sensor ignore a nearby background? | [BGS-CX61 configuration](/products/photoelectric-sensor/bgs-cx61-focused-beam-background-suppression-photoelectric-sensor/) Does the panel accept the selected switching output? | [NPN/PNP current-path guide](/guides/npn-vs-pnp-outputs-explained/) ### Category FAQ Q: Which photoelectric sensor is best for dark or shiny objects? A: A through-beam pair is the strongest starting point because the target is detected by interrupting the beam rather than by returning a certain amount of reflected light. Application testing is still required for partially transparent targets. Q: What is a through-beam photoelectric sensor? A: It is an opposed emitter and receiver pair. The receiver output changes when an object blocks the optical path between the two housings. Q: What is the difference between diffuse reflective and background suppression? A: Both work from one side. A standard diffuse sensor switches from target-reflected light; a BGS sensor is designed to distinguish a target from a background beyond a set distance. Q: Are background-suppression photoelectric sensors the same as ToF sensors? A: No. Background suppression describes the application result, not one universal ranging technology. A product should only be called time-of-flight when its first-party specification explicitly states that principle. Q: Which H-M model gives a 15 m through-beam range? A: The M18 H1815M range class is published at 15 m ±10%. Choose its NPN/PNP and output-logic suffix from the product model table. Q: Can a general photoelectric sensor replace a safety light curtain? A: No. The products on this category page are for automation detection, not safety-rated personnel protection. ### BGS-CX441 / BGS-CX442 Background Suppression Photoelectric Sensor URL: https://www.daidisensor.com/products/photoelectric-sensor/bgs-cx441-bgs-cx442-background-suppression-photoelectric-sensor/ BGS-CX441/CX442 background suppression photoelectric sensors: 2 mm or 15 mm spot, 10-300 mm adjustable range, 0.5 ms response, IP65, NPN/PNP output. - BGS-CX441 offers an adjustable sensing distance of 10-100 mm with an 80 mm black/white differential distance (100 mm on white paper). - BGS-CX442 offers an adjustable sensing distance of 20-300 mm, extending to 500 mm on white targets, with a 280 mm black/white differential distance. - BGS-CX441 uses a 2 mm infrared spot; BGS-CX442 uses a 15 mm wide spot for detection on perforated or textured surfaces. - Both models respond in under 0.5 ms with a 100 Hz switching frequency. ### BGS-CX61 Focused-Beam Background Suppression Photoelectric Sensor URL: https://www.daidisensor.com/products/photoelectric-sensor/bgs-cx61-focused-beam-background-suppression-photoelectric-sensor/ BGS-CX61 background suppression photoelectric sensor: 2 mm focused spot, under 0.5 ms response, IP67 rated, NPN/PNP open-collector output, DC12-24V. - The BGS-CX61 background-suppression photoelectric sensor projects a focused 2 mm light spot and responds in under 0.5 ms. - BGS-CX61N provides NPN open-collector output; BGS-CX61P provides PNP open-collector output. - The BGS-CX61's white control wire selects Light-ON or Dark-ON operation on site: unconnected for Light-ON, connected to the blue wire for Dark-ON. - The BGS-CX61 operates on DC 12-24V (±10%) with current consumption under 30 mA and is rated IP67 per IEC 60529. ### BX Series Long-range Background Suppression (BGS) Photoelectric Sensor URL: https://www.daidisensor.com/products/photoelectric-sensor/bx-series-long-range-background-suppression-photoelectric-sensor/ BX series long-range background suppression photoelectric sensor detects targets up to 4000 mm from one side, no reflector, 2 ms response, DC12-24V. - The BX-H4000 background suppression photoelectric sensor has an adjustable sensing range of 50-4000 mm. - BX-G2000 and BX-S2000 are diffuse reflective sensors with an adjustable range of 30-2000 mm. - All BX series sensors have a 2 ms response time and operate on DC12-24V. - BX-H4000 is available in NPN (BX-H4000NPN) and PNP (BX-H4000PNP) output versions. ### DD-301/401/302/402 Series Reflective Photoelectric Sensor (Wire-lead Type) URL: https://www.daidisensor.com/products/photoelectric-sensor/dd-301-401-302-402-series-reflective-photoelectric-sensor/ DD-301/401/302/402 reflective photoelectric sensor: 5mm detection range, DC5-24V supply, NPN output, 940nm infrared, 500Hz switching frequency, IP50 rated. - The DD-301/401/302/402 series is a diffuse-reflective NPN photoelectric sensor rated for a 5mm detection distance against a 90% reflectance white paper target. - DD-301 and DD-302 are Dark-ON (output ON when the beam is blocked); DD-401 and DD-402 are Light-ON (output ON when reflected light is received). - DD-301/DD-401 are horizontal (side-sensing) models; DD-302/DD-402 are vertical (top-sensing) models. - The sensor operates on a DC5-24V ±10% supply, covering both 5V logic-board and 24V industrial-control applications. ### DD-T21 / DD-T31 / DD-D21 Compact Self-Contained Photoelectric Sensor URL: https://www.daidisensor.com/products/photoelectric-sensor/dd-t21-dd-t31-dd-d21-compact-self-contained-photoelectric-sensor/ DD-T21/T31/D21 compact photoelectric sensors: built-in amplifier, NPN NO output, 1.5m/2.5m through-beam or 150mm diffuse, 1ms response, DC10.8-26.4V. - DD-T21 and DD-T31 are through-beam photoelectric sensors with an infrared light source, detecting at 1.5 m and 2.5 m respectively. - DD-D21 is a diffuse-reflective photoelectric sensor with a 150 mm detection range and on-site adjustable sensitivity. - All three models in the DD-T21/T31/D21 series output NPN, Normally Open (NO), and operate on 10.8-26.4 VDC (nominal 12-24 VDC). - The series has a response time of 1 ms, a maximum current consumption of 20 mA, and a minimum detectable object size of 6 mm. ### DK-D461 / DK-D561 Strip-beam (Line-beam) Photoelectric Sensor URL: https://www.daidisensor.com/products/photoelectric-sensor/dk-d461-dk-d561-strip-beam-photoelectric-sensor/ DK-D461/DK-D561 strip-beam photoelectric sensors: 4mm x 100mm line beam, background-suppression sensing to 200mm, 1ms response, IP65, DC12-24V, NPN/PNP. - The DK-D461 photoelectric sensor emits a strip-shaped light beam 4 mm wide and up to 100 mm long, in place of a conventional round point spot. - The DK-D461 uses distance-settable (background-suppression) reflective sensing with a detection distance within 200 mm. - Repeatability is 1 mm along the sensing axis and 0.2 mm perpendicular to it, with hysteresis under 2% of the operating distance. - Ambient light immunity is rated up to 3,000 lx incandescent and 10,000 lx sunlight at the receiver. ### DX-15/30/50/100 Series Ultra-thin Through-beam Photoelectric Sensor URL: https://www.daidisensor.com/products/photoelectric-sensor/dx-15-30-series-ultra-thin-self-contained-photoelectric-sensor/ DX series ultra-thin through-beam photoelectric sensor: emitter/receiver pairs at 150, 300, 500 and 1000mm, front-sensing (F) or side-sensing (L), NPN or PNP, N.O./N.C. switchable, detects 1mm objects. - The DX series is a through-beam (opposed) sensor: each model number is a matched emitter/receiver pair, not a single reflective unit. Detection occurs when an object breaks the beam between the two housings. - Detection distances across the series are 150 mm (DX-15), 300 mm (DX-30), 500 mm (DX-50L / DX-50F) and 1000 mm (DX-100L / DX-100F). - Both optical layouts are available at every distance: front-sensing (beam along the housing axis) and side-sensing (beam turned 90 degrees for rail-side or panel-gap mounting). - On the 500 mm and 1000 mm models the model code carries an L or F suffix — L = side-sensing, F = front-sensing — and an (N/P) option for NPN or PNP output. ### E3JK Square Photoelectric Sensor (Relay & Transistor Output) URL: https://www.daidisensor.com/products/photoelectric-sensor/e3jk-square-photoelectric-sensor/ E3JK square photoelectric sensors: diffuse 0.5/1.5m, retro-reflective 4m, through-beam 15m, relay 3A or NPN/PNP output, 90-250VAC/10-30VDC, IP55. - E3JK relay-output versions switch loads up to 3 A directly from the sensor's built-in relay contact. - E3JK diffuse-reflective (DS30) models detect at 0.5 m or 1.5 m (±10%); retro-reflective (R4) models detect at 4 m (±10%); through-beam (5DM) models detect at 5 m (relay) or up to 15 m (transistor). - E3JK relay versions are offered for 90-250 VAC, 10-30 VDC, or universal 10-250 V AC/DC supply. - The E3JK through-beam transistor line is available only in normally-open (NO) logic — E3JK-5DM2 and E3JK-5DM4 (normally-closed) do not exist in this series. ### E3Z Compact Photoelectric Sensor URL: https://www.daidisensor.com/products/photoelectric-sensor/e3z-compact-photoelectric-sensor/ E3Z compact photoelectric sensor: 31×11×22mm housing, diffuse-reflective 30-100/200/300mm or through-beam 5m detection, NPN/PNP output, IP65, 10-30VDC. - The E3Z series diffuse-reflective sensors are offered in three adjustable sensing ranges: 30-100mm, 30-200mm, and 30-300mm. - The E3Z series through-beam version has a sensing distance of 5 meters. - The E3Z series housing measures 31 × 11 × 22 mm and is made of PBT plastic. - The E3Z series is rated IP65 and operates on a 10-30VDC supply. ### H-M Series M12/M18 Through-beam Photoelectric Sensor URL: https://www.daidisensor.com/products/photoelectric-sensor/h-m-series-m12-m18-through-beam-photoelectric-sensor/ H-M series M12/M18 through-beam photoelectric sensors: 16 models, 2-15 m sensing range, NPN/PNP NO/NC outputs, 10-30VDC, nickel-plated brass barrel. - The H1815M through-beam sensor pair reaches a sensing range of up to 15 m +/-10% from a single M18 emitter/receiver pair. - The H-M series through-beam sensors are available in four sensing-range classes: 2 m, 5 m (M12), 5 m and 15 m (M18), each with +/-10% tolerance. - N2 and P2 output versions provide complementary normally-open (N.O.) and normally-closed (N.C.) signals from a single receiver. - The M12 barrel measures M12x63 mm and the M18 barrel measures M18x73 mm, both machined from nickel-plated brass. ### How the H-M Through-Beam Sensor Pair Works The emitter sends a continuous optical beam across the detection zone to the receiver. With the path clear, the receiver sees the emitter; when a target blocks the path, the receiver changes its output state. That opposed layout is why the H-M **through-beam photoelectric sensor** is much less dependent on the target's colour or gloss than a sensor that must read reflected light. The trade-off is mechanical: both sides need mounting and power/cabling, and the two M12 or M18 barrels must share the same optical axis. Choose the range class from the real installed span, then allow alignment margin rather than specifying exactly at the published maximum. Figure context: Emitter and receiver face each other; beam interruption—not target reflectivity—changes the output. ### H122M, H125M, H1805M or H1815M? Range class | Barrel | Published sensing range | Start here when H122M | M12 × 63 mm | 2 m ±10% | the span is short and the mounting hole is M12 H125M | M12 × 63 mm | 5 m ±10% | a compact M12 pair must cover a wider conveyor H1805M | M18 × 73 mm | 5 m ±10% | the installation uses an M18 barrel H1815M | M18 × 73 mm | 15 m ±10% | a gate, portal or long conveyor needs the longest H-M class After the range/body choice, select N1 or P1 for a single normally-open output, or N2/P2 for complementary normally-open plus normally-closed outputs. For other sensing principles and housings, return to the [photoelectric sensor range](/products/photoelectric-sensor/). ### H-series Micro Diffuse Photoelectric Sensor (M3-M6) URL: https://www.daidisensor.com/products/photoelectric-sensor/h-series-micro-diffuse-photoelectric-sensor/ H-series M3-M6 micro diffuse photoelectric sensors: 32 models, 5-200mm adjustable range, NPN/PNP, IP65 stainless housing, 940nm infrared, 10-30VDC. - The H-series M3-M6 micro diffuse photoelectric sensors offer adjustable sensing ranges from 5mm up to 200mm, depending on thread size and model. - Each of the four thread sizes (M3, M4, M5, M6) in the H-series is available in two adjustable sensing-range bands, with NPN/PNP output and N.O./N.C. logic, for a total of 32 part numbers. - The H-series sensor housing is stainless steel with an IP65 protection rating. - The H-series uses a 940nm infrared emitter and operates on a 10-30VDC supply with a 120mA load current, 5ms response time, and 100Hz response frequency. ### H08 / R12 Series Micro Diffuse-Reflective Photoelectric Sensor (M8/M12) URL: https://www.daidisensor.com/products/photoelectric-sensor/h08-r12-series-micro-diffuse-reflective-photoelectric-sensor/ H08/R12 series M8/M12 threaded diffuse-reflective photoelectric sensors: 20 models, sensing range up to 300mm, IP65 nickel-plated brass, 10-30VDC NPN/PNP. - The H08/R12 series comprises 20 models across M8 and M12 threaded barrel sizes, each available in NPN/PNP and N.O./N.C. output combinations. - The R12300 model offers the longest sensing range in the series, rated 30-300 mm, using an M12 threaded metal barrel. - H08 and R12 sensors use an infrared light source at 850/940 nm and operate on 10-30VDC supply voltage. - The sensor housing is nickel-plated brass with an IP65 ingress protection rating. ### JNS18 & JNK18 Series M18 Diffuse Photoelectric Sensor URL: https://www.daidisensor.com/products/photoelectric-sensor/jns18-and-jnk18-series-m18-diffuse-photoelectric-sensor/ JNS18 & JNK18 M18 diffuse photoelectric sensors: 10-30 VDC, IP65, sensing range 100 mm to 3 m, NPN/PNP, N.O./N.C. outputs, no reflector required. - The JNK18-300D variant of the JNK18 series delivers a rated diffuse sensing distance of 3 m in a standard M18-threaded barrel housing. - The JNS18 series is available in three sensing-distance options — 10 cm, 30 cm, and 50 cm — each offered with NPN or PNP, normally-open or normally-closed output. - The JNK18 series' DN2 and DP2 output variants provide complementary normally-open and normally-closed signals simultaneously from a single sensor. - Both JNS18 and JNK18 series operate on a 10-30 VDC supply and carry an IP65 ingress-protection rating. ### PZ-CM10 Vision-based One-touch Teach Photoelectric Sensor URL: https://www.daidisensor.com/products/photoelectric-sensor/pz-cm10-vision-based-one-touch-teach-photoelectric-sensor/ PZ-CM10 vision-based one-touch teach photoelectric sensor: SET-button teach, 3-wire NPN/PNP output, response time ≤0.5 ms, DC12-24V ±10%, IP65/IP66. - The PZ-CM10 completes target setup with a single press of its SET button, without external software or programming. - The PZ-CM10 uses a standard 3-wire output (brown +, blue -, black signal), with NPN or PNP selectable to order. - The PZ-CM10's rated response time is 0.5 milliseconds or less. - The PZ-CM10 operates on a DC12-24V ±10% supply and carries an IP65/IP66 ingress protection rating. ### PZ-MK10 One-Touch Teach Laser Sensor URL: https://www.daidisensor.com/products/photoelectric-sensor/pz-mk10-one-touch-teach-laser-sensor/ PZ-MK10 one-touch teach laser sensor: setting distance 10-500mm on light backgrounds, 10-200mm on dark backgrounds, 200mm diffuse mode. 3-wire, 2m cable. - The PZ-MK10 laser sensor is taught via a single push-button (one-touch teach) against the sensor's actual installed background. - With a light background or reflector present, the PZ-MK10's specified setting distance range is 10-500 mm. - Against a dark background, the PZ-MK10's specified setting distance range is 10-200 mm. - With no background present, the PZ-MK10 operates as a standard diffuse-reflective photoelectric sensor at a 200 mm detection distance. ### QF-35 M8 Diffuse-Reflective Photoelectric Sensor URL: https://www.daidisensor.com/products/photoelectric-sensor/qf-35-m8-diffuse-reflective-photoelectric-sensor/ QF-35 M8 diffuse-reflective photoelectric sensor: 35 mm sensing distance, IP66 stainless housing, 940 nm infrared, DC12-24V supply, 3 ms response, NPN/PNP. - The QF-35 M8 diffuse-reflective photoelectric sensor has a rated sensing distance of 35 mm, calibrated against a 30×30 mm white paper target. - The QF-35 is rated IP66 per IEC 60529, designed to withstand powerful water jets. - The QF-35 uses a 940 nm infrared emitter and offers NPN (QF-35N1) or PNP (QF-35P1) Normally Open output. - The QF-35's operate/reset response time is 3 ms or less, and its output is rated for loads up to 80 mA at DC24V or below. ## color-mark-sensor Category URL: https://www.daidisensor.com/products/color-mark-sensor/ ### Choose Registration-Mark Detection or Colour Recognition Detecting a registration mark against its background is not the same task as distinguishing several colours. Define the printed mark, background, surface finish, working distance and required control result before comparing sensor housings. Test the actual printed stock, not only a colour description. ### Compare the Configuration Paths Required task | Existing product page | What to confirm Remote mark-detection arrangement | [JNS-W70 / JNS-W500 options](/products/color-mark-sensor/jns-w70-jns-w500-long-range-color-mark-sensor/) | Select the appropriate working-distance model and verify the target/mark combination. Packaging registration marks | [FS-S72 switching configurations](/products/color-mark-sensor/fs-s72-color-mark-sensor/) | Check output polarity, target contrast and mounting geometry. Colour-sensing configuration | [CZ-V21 amplifier-separate family](/products/color-mark-sensor/cz-v21-rgb-digital-color-sensor/) | Confirm head/amplifier compatibility and the colour-selection task. ### Prepare Printed Samples for a Comparable Trial Purchase input | Information to provide Print samples | Include the smallest mark, background colours, gloss, transparent film and normal print variation. Mechanical and timing input | State distance, mark orientation, web movement, speed and available teaching access. Order contents | List sensor head, amplifier if required, cables and the required output/logic together. For a simple gap or edge passing through a fixed opening, compare [slot sensors](/products/slot-sensor/). For difficult background geometry, compare [photoelectric modes](/products/photoelectric-sensor/) and test the same sample. Send the application details and required configuration through the [inquiry form](/contact/) so that the quotation identifies the selected equipment and options. ### CZ-V1 High-Precision Color Sensor URL: https://www.daidisensor.com/products/color-mark-sensor/cz-v1-high-precision-color-sensor/ CZ-V1 high-precision color sensor: 4-channel amplifier discriminates 1,000+ colors, teaches 4 target colors, 200 μs HSP response, NPN/PNP 12-24VDC output. - The CZ-V1 color sensor amplifier discriminates more than 1,000 colors and can teach up to four target colors in a single unit. - CZ-V1 (NPN, max. 40 VDC / 100 mA) and CZ-V1P (PNP) are the two amplifier output versions of the CZ-V1 color sensor. - The CZ-V1 offers two response-time settings: 200 μs in HSP mode and 1 ms in FINE mode. - The CZ-V1 supports selectable match (ON on match) or mismatch (ON on mismatch) output logic. ### CZ-V21 RGB Digital Color Sensor (Amplifier-Separate Type) URL: https://www.daidisensor.com/products/color-mark-sensor/cz-v21-rgb-digital-color-sensor/ CZ-V21 RGB digital color sensor: 8 channels, 3,000+ color discrimination, NPN/PNP output, and two interchangeable sensor heads for glare or texture. - The CZ-V21 amplifier has 8 independent detection channels and can be configured to detect 4 or 8 colors simultaneously. - The CZ-V21 discriminates over 3,000 colors. - The CZ-C35 sensor head has a detection distance of 28–52mm; the CZ-C37 sensor head has a detection distance of 11–20mm and is a luster-cancellation, small-beam-spot design for glossy or metallic surfaces. - The CZ-V21 (NPN) outputs a maximum of 40VDC and the CZ-V21P (PNP) outputs a maximum of 30VDC, each with 4 channels rated at 100mA per channel, 200mA total. ### FS-S72 Color Mark Sensor (FS-S72 NPN / FS-S72P PNP) URL: https://www.daidisensor.com/products/color-mark-sensor/fs-s72-color-mark-sensor/ FS-S72 color mark sensor: 24VDC, 18-28mm sensing range, sub-200μs response. NPN (FS-S72) or PNP (FS-S72P) output for packaging and labeling machines. - The FS-S72 color mark sensor has a response time of 200 microseconds or less. - The FS-S72 operates on a 24VDC power supply with a sensing distance of 18-28mm. - FS-S72 provides NPN open-collector output; FS-S72P provides PNP open-collector output, within the same sensor series. - The FS-S72 supports two operating modes: mark (contrast) detection mode and color mode, switching output ON on mark detection or on color match respectively. ### JNS-W70 / JNS-W500 Long-Range Color Mark Sensor URL: https://www.daidisensor.com/products/color-mark-sensor/jns-w70-jns-w500-long-range-color-mark-sensor/ JNS-W70/JNS-W500 long-range color mark sensor: 30-70mm/50-500mm range, white LED, switchable NPN/PNP, N.O./N.C. logic, IO-Link, 10-30VDC, IP65 rated. - The JNS-W500 color mark sensor detects at 50-500mm and the JNS-W70 at 30-70mm. - Both JNS-W70 and JNS-W500 use a white LED emitter. - The JNS-W series provides switchable NPN/PNP open-collector output (≤30V, ≤100mA, residual voltage ≤2V) with selectable N.O./N.C. logic on a single unit. - The JNS-W series supports IO-Link communication in addition to discrete output. ### PZ-LX101 Color Mark Sensor URL: https://www.daidisensor.com/products/color-mark-sensor/pz-lx101-color-mark-sensor/ PZ-LX101 color mark sensor: NPN output, selectable Light-ON/Dark-ON logic, 8-25mm sensing range, 12-24VDC supply, for packaging and labeling lines. - The PZ-LX101 is an NPN-output color mark (contrast) sensor with a sensing range of 8-25 mm. - The PZ-LX101 offers a selectable Light-ON / Dark-ON output, allowing one sensor to detect either a dark mark on a light background or a light mark on a dark background. - The PZ-LX101 operates on a 12-24 VDC supply. - The PZ-LX101 provides two operating modes, MARK mode and C/C1 mode, each with an independently rated response time. ## proximity-sensor Category URL: https://www.daidisensor.com/products/proximity-sensor/ ### Choose an Industrial Proximity Sensor in Four Steps Start with the target, not the thread size. An **inductive proximity sensor** detects metal without contact; a **capacitive proximity sensor** can also detect non-metal targets such as plastic, glass, powder or liquid when the application is validated. Then choose the mounting geometry, sensing distance and output that match the machine input. The catalogue below covers cylindrical M3, M4, M5, M6, D6.5, M8, M12, M18 and M30 bodies, compact square housings, cable and quick-disconnect versions, flush and non-flush mounting, NPN or PNP outputs, and selected 2-wire DC or AC families. Use the decision map first, then open the matching series card for its exact model table. Figure context: Target material → mounting → sensing distance → electrical output: decide in that order. ### Choose Inductive or Capacitive by Target Material Choose inductive for repeatable detection of steel, aluminium and other metal machine parts. It is the default for gear teeth, cylinder positions, fixtures and end stops because the sensing principle responds to conductive metal rather than surface colour. Choose capacitive when the target is non-metal or must be detected through a non-metal wall; the catalogue includes M8, M12, M18, M30 and square capacitive families. Capacitive sensing is more application-dependent because material density, moisture, container wall thickness and nearby metal affect the usable setting. For a new material, treat the published nominal range as a selection starting point and validate the actual target before production release. Question | Inductive | Capacitive Best target | metal | metal and non-metal Typical duty | position, end stop, gear or fixture | plastic, glass, powder or liquid presence Common bodies here | M3 to M30 and square | M8 to M30 and Q20 square Application check | target metal changes usable distance | validate material, wall and surrounding metal ### M8, M12, M18 or M30 Proximity Sensor? Thread size controls far more than the mounting hole. Small M8 and sub-M8 sensors fit grippers, compact slides and narrow brackets; M12 is the general machine-building size; M18 and M30 bodies provide room for longer nominal distances and more robust mounting. If the existing hole must stay, choose the thread first and compare only the ranges available in that body. For a common threaded industrial range, start with the [M8 inductive series](/products/proximity-sensor/m8-inductive-proximity-sensors/), [M12 short-body series](/products/proximity-sensor/m12-inductive-proximity-sensors/), or [M18/M30 inductive series](/products/proximity-sensor/m18-m30-inductive-proximity-sensors/). For a cost-led M8–M30 platform, compare the [JNX/JNS economy family](/products/proximity-sensor/economy-inductive-proximity-sensors-m8-m12-m18-m30/). Body class | Use it when | Representative family M3–M6 / D6.5 | the installation is smaller than a standard M8 mount | [M3/M4/M5 separate-amplifier](/products/proximity-sensor/m3-m4-m5-short-body-separate-amplifier-inductive-proximity-switches/), threaded M4/M5/M6, D6.5 M8 | compact industrial mounting and short sensing distances | M8 inductive or M8 capacitive M12 | general machine position sensing | M12 short-body, JM12 connector, capacitive M12 M18 / M30 | longer nominal distance or a larger mounting body | M18/M30 inductive and capacitive families Square | a threaded barrel cannot fit or the sensing face must turn sideways | Q08, Q10, Q17/Q18C, Q25/Q30/Q40 ### Select the Mounting Style and Required Clearance A flush sensor can be embedded with its sensing face level with surrounding metal. A non-flush sensor needs free space around the sensing face because its field extends sideways as well as forward. Non-flush versions often provide a longer nominal distance in the same diameter, but installing one inside a metal pocket can reduce range or keep the output permanently active. Our model names and tables identify the mounting style for each family; do not infer it from body length alone. The visual below shows the mechanical difference before you choose the bracket; the [proximity sensor selection guide](/guides/how-to-choose-a-proximity-sensor/) keeps the detailed comparison in one place. Figure context: Flush sits level with metal; non-flush needs a clear zone around the active face. ### NPN, PNP, 2-Wire, Cable or Connector For 3-wire DC sensors, match NPN or PNP to the receiving PLC input rather than choosing by region or habit. Normally-open and normally-closed logic is a separate decision. The [NPN vs PNP output guide](/guides/npn-vs-pnp-outputs-explained/) explains the current path; the series pages list the actual suffixes. Choose a molded cable where vibration resistance and a sealed permanent lead matter. Choose a quick-disconnect connector where maintenance teams need fast replacement without pulling a new cable. The [JM12 M12 connector series](/products/proximity-sensor/jm12-series-m12-inductive-proximity-sensor-with-m12-aviation-connector/) and [JM M18/M30 connector series](/products/proximity-sensor/jm-series-m18-m30-connector-type-inductive-proximity-sensors/) are the direct starting points. If the circuit specifically requires two conductors, use the [DC 2-wire family](/products/proximity-sensor/m8-m12-m18-m30-dc-2-wire-inductive-proximity-sensors/) or [AC 2-wire family](/products/proximity-sensor/m12-m18-m30-2-wire-ac-inductive-proximity-sensors/) instead of adapting a 3-wire output. ### Compact and Long-Range Proximity Sensor Options For compact fixtures, published family envelopes begin with M3/M4/M5 models around 0.6–1.5 mm and M8 families around 1–6 mm. Standard M12 inductive families extend through the published options on their product pages, while selected M18/M30 non-flush inductive models publish the longest catalogue distances in this category, up to 40 mm. Selected adjustable capacitive families publish options up to 30 mm. These are family envelopes, not a promise for every model or target. The selected housing, flush/non-flush mounting and target material determine the rated distance, and a production design should keep operating margin instead of mounting exactly at the catalogue limit. ### What Affects the Cost of a Proximity Sensor? Quotation depends on sensing principle, body size and shape, sensing distance, flush/non-flush construction, 2-wire or 3-wire circuit, AC or DC supply, NPN/PNP and N.O./N.C. logic, molded cable or connector, cable length and order quantity. We do not publish one flat price because those choices change the part itself. For a comparable quotation, send the target material, required operating gap, housing size, mounting style, supply voltage, output logic, cable or connector preference and quantity. Have those application facts ready? Send them through the [inquiry form](/contact/) for a model-level recommendation and quotation. ### Build a Replacement or New-Machine Order Specification Send the existing sensor label and bracket drawing for a replacement. Record thread diameter, usable body length, sensing-face position, target metal, operating gap, supply, switching logic and cable or connector. A matching M12 thread is not proof of electrical or sensing equivalence. Configuration question | Compare these catalogue options Need a detachable connector in an M8 mount? | [JM8 quick-disconnect configurations](/products/proximity-sensor/jm8-series-quick-disconnect-inductive-proximity-sensors/) Need a short M12 body? | [M12 body-length choices](/products/proximity-sensor/m12-inductive-proximity-sensors/) Need non-metal target detection? | [M8 capacitive cable models](/products/proximity-sensor/m8-capacitive-proximity-switch/) Unsure about target or mounting clearance? | [Proximity selection guide](/guides/how-to-choose-a-proximity-sensor/) For a sample check, include the real bracket and target rather than testing in free air only. Record the order code and test setup so subsequent production orders use the same configuration. ### Category FAQ Q: What does an industrial proximity switch detect? A: An inductive proximity switch detects metal. A capacitive proximity switch can detect metal and selected non-metal targets, but its final sensing performance should be validated with the actual material and mounting. Q: How do I choose an M8, M12, M18 or M30 proximity sensor? A: Start with the available mounting hole and mechanical clearance, then confirm that the body size offers the required nominal sensing distance and output. Larger threads often offer longer ranges, but the exact value belongs to the series model table. Q: What is the difference between flush and non-flush proximity sensors? A: Flush models can be embedded level with surrounding metal. Non-flush models require clearance around the active face; they often reach farther, but a metal pocket can disturb their field. Q: Should I choose an NPN or PNP proximity sensor? A: Match the sensor to the PLC or controller input circuit. NPN is a sinking output and PNP is a sourcing output; neither is universally better. Q: Can a capacitive proximity sensor detect through a plastic container? A: Potentially, yes. The usable result depends on the container wall, target dielectric properties, moisture and surrounding metal, so validate the real container and fill material before production use. Q: Which proximity sensor should I use when a cylindrical body will not fit? A: Use a square family and choose its sensing-face direction. The catalogue includes Q08, Q10, Q17/Q18C, Q20 and Q25/Q30/Q40 bodies for compact, side-sensing or larger-distance layouts. ### D6.5 Series Inductive Proximity Sensors (Ultra-Short 18mm / Y-Type / 35mm / 45mm) URL: https://www.daidisensor.com/products/proximity-sensor/d6-5-series-inductive-proximity-sensors/ D6.5 Series inductive proximity sensors: 6.5mm diameter, 10-30VDC, 1-6mm sensing distance, NPN/PNP NO/NC, IP67, ultra-short 18mm/Y-type/35mm/45mm bodies. - This inductive proximity sensor series has a 6.5mm barrel diameter and is offered in four body configurations: ultra-short (18mm), right-angle Y-type (18mm), 35mm, and 45mm. - Sensing distance across the series ranges from 1mm to 6mm, depending on body length and flush/non-flush mount type. - The series operates on 10-30VDC, 3-wire DC wiring, with selectable NPN or PNP output and NO or NC switching. - Response time is 0.1ms on most models (0.2ms on the 4mm non-flush 35mm variant), with switching frequency up to 2kHz on the shortest-range models. ### Economy Inductive Proximity Sensors M8/M12/M18/M30 (JNX/JNS Series) URL: https://www.daidisensor.com/products/proximity-sensor/economy-inductive-proximity-sensors-m8-m12-m18-m30/ Economy inductive proximity sensors (JNX/JNS series) in M8/M12/M18/M30, sensing 1-15mm, IP67, 10-30VDC 3-wire, NPN/PNP NO/NC, -25°C to +70°C, 0.1ms response. - The M8/M12/M18 economy inductive proximity sensors in this series have a response time of 0.1ms and a switching frequency of up to 1KHz. - Sensing distance ranges from 1mm (M8 flush) up to 15mm (M30 non-flush) across the JNX/JNS economy series. - All models operate on 10-30VDC, 3-wire DC wiring, with NPN or PNP output in normally-open or normally-closed configuration. - The sensor housing is rated IP67 and the operating temperature range is -25°C to +70°C. ### Economy M4/M5/M6 Inductive Proximity Switches (Export-Grade) URL: https://www.daidisensor.com/products/proximity-sensor/economy-m4-m5-m6-inductive-proximity-switches/ Economy M4/M5/M6 inductive proximity switches, export-grade: 1.0mm sensing distance, NPN/PNP, NO/NC output, copper body, 25-35mm lengths for tight spaces. - The M4 non-threaded proximity switch (JJ4A3-1 series) has a 30mm body length and 4mm diameter, with a confirmed sensing distance of 1.0mm ± 10%. - The M5 threaded proximity switch (JJ5A3-1 series, M5 x 0.5 thread) has a 30mm body length, is rated for flush (shielded) mounting, and has a confirmed sensing distance of 1.0mm ± 10%. - The M6 threaded proximity switch (JJ6A3-1 series, M6 x 0.75 thread) has a 35mm body length, is rated for flush (shielded) mounting, and has a confirmed sensing distance of 1.0mm ± 10%. - Each size in this series is available in NPN output (model suffix ZB) or PNP output (model suffix ZA), with normally-open (suffix X) or normally-closed (suffix Y) contact configuration. ### High-Quality Threaded M4/M5/M6 Inductive Proximity Sensors URL: https://www.daidisensor.com/products/proximity-sensor/high-quality-threaded-m4-m5-m6-inductive-proximity-sensors/ High-Quality Threaded M4/M5/M6 inductive proximity sensor series: M4 0.6-1.0mm, M5/M6 0.8-1.5mm sensing distance, NPN/PNP, NO/NC output, 3-wire DC, 44 models. - The M4/M5/M6 threaded inductive proximity sensor series is available in three thread sizes: M4x0.5 (25mm body), M5 (25mm body), and M6 (35mm body). - Each size in this series offers selectable NPN or PNP output combined with normally-open (NO) or normally-closed (NC) logic. - M4 models cover sensing distances of 0.6mm, 0.8mm, and 1.0mm; M5 and M6 models cover 0.8mm, 1.0mm, 1.2mm, and 1.5mm. - All models in this series use a 3-wire DC wiring connection. ### JD Series 3-Wire Connector-Type Inductive Proximity Sensors D6.5-M8 / D6.5-M12 URL: https://www.daidisensor.com/products/proximity-sensor/jd-series-3-wire-connector-type-inductive-proximity/ JD Series D6.5 inductive proximity sensor with M8/M12 connector: 6.5mm probe, 1-6mm sensing distance, 10-30VDC, IP67, NPN/PNP NO/NC 3-wire output. - The JD Series inductive proximity sensor has a 6.5mm probe diameter and terminates in an M8 (3-pin) or M12 (4-pin) circular connector instead of a fixed cable. - Flush-mount JD Series variants provide 1mm, 2mm, or 3mm sensing distance; non-flush variants provide 2mm, 4mm, or 6mm. - The JD Series operates on 10-30VDC, with a maximum load current of 150mA and an overload protection point of 180mA. - The JD Series is rated IP67 and operates across a -25°C to +70°C ambient temperature range. ### JM Series M18/M30 Connector-Type Inductive Proximity Sensors (M12 Quick-Disconnect) URL: https://www.daidisensor.com/products/proximity-sensor/jm-series-m18-m30-connector-type-inductive-proximity-sensors/ JM series M18/M30 inductive proximity sensors with M12 4-pin quick-disconnect connector, 10-30VDC, IP67, sensing distance up to 40mm, NPN/PNP NO/NC. - The JM18 series is available in flush-mount sensing distances of 5mm, 8mm, and 12mm, and non-flush sensing distances of 8mm, 16mm, and 20mm. - The JM30 series is available in flush-mount sensing distances of 10mm, 15mm, and 22mm, and non-flush sensing distances of 15mm, 25mm, and 40mm. - JM series inductive proximity sensors operate on a 10-30VDC supply with an IP67 protection rating. - The JM series terminates in an M12, 4-pin connector for quick-disconnect wiring instead of a fixed cable. ### JM12 Series M12 Inductive Proximity Sensor with M12 Aviation (Quick-Disconnect) Connector URL: https://www.daidisensor.com/products/proximity-sensor/jm12-series-m12-inductive-proximity-sensor-with-m12-aviation-connector/ JM12 series M12x1 inductive proximity sensor with M12 4-pin aviation connector for tool-free swap. 2-10mm sensing distance, NPN/PNP, NO/NC, IP67, 10-30VDC. - The JM12 series is a DC 3-wire inductive proximity sensor with an M12x1 threaded barrel and an M12 4-pin aviation connector, available in 40mm, 50mm, and 68mm body lengths. - Sensing distance across the JM12 series ranges from 2mm to 10mm, depending on body length and flush/non-flush mounting type. - The JM12 series operates on 10-30VDC with a maximum load current of 150mA and includes built-in short-circuit protection with an overload trip point of 180mA. - The JM12 housing is rated IP67 and carries an operating temperature range of -25°C to +70°C. ### JM8 Series Quick-Disconnect (Connector-Type) Inductive Proximity Sensors URL: https://www.daidisensor.com/products/proximity-sensor/jm8-series-quick-disconnect-inductive-proximity-sensors/ JM8 series M8 inductive proximity sensors use an M8 or M12 quick-disconnect connector, 1-6mm sensing distance, IP67, 10-30VDC, NPN/PNP, NO/NC, 32-70mm bodies. - The JM8 series inductive proximity sensor uses an M8 or M12 quick-disconnect connector, allowing sensor replacement without cutting or re-terminating cable. - JM8 sensing distances are confirmed at 1mm, 2mm, 3mm, 4mm, and 6mm across model codes JM801 through JM806. - JM8 series operates on 10-30VDC three-wire DC power with a maximum load current of 150mA and no-load current under 10mA. - The JM8 housing carries an IP67 protection rating and is specified for -25°C to +70°C operation. ### M12 Inductive Proximity Sensors (22mm/35mm/45mm Short-Body) URL: https://www.daidisensor.com/products/proximity-sensor/m12-inductive-proximity-sensors/ M12x1 inductive proximity sensors in 22mm, 35mm and 45mm bodies with flush/non-flush mounting, NPN/PNP NO/NC outputs, IP67 housing, and 0.1ms response time. - This M12x1 inductive proximity sensor series is offered in three body lengths - 22mm, 35mm, and 45mm - each available in flush and non-flush mounting. - Sensing distance ranges from 2mm to 6mm for flush-mount variants and 4mm to 10mm for non-flush variants across the 22/35/45mm body family. - The sensor operates on 10-30VDC three-wire DC supply with a maximum load current of 150mA and no-load current below 10mA. - Response time is as fast as 0.1ms, with switching frequency up to 1.5KHz on the fastest variant. ### M12/M18/M30 2-Wire AC Inductive Proximity Sensors URL: https://www.daidisensor.com/products/proximity-sensor/m12-m18-m30-2-wire-ac-inductive-proximity-sensors/ M12/M18/M30 2-wire AC inductive proximity sensors wire directly into 20-250V AC circuits, 2-16mm sensing distance, IP67 rated, -25 to 70C, 24 models. - This M12/M18/M30 series is a 2-wire inductive proximity sensor designed to be wired directly in series with a 20-250V AC load, using only its brown and blue leads. - Sensing distances in this AC series range from 2mm (M12, flush mount) to 16mm (M18/M30, non-flush mount). - The series is rated IP67 with an operating temperature range of -25°C to +70°C. - Maximum load current is 400mA, with a rated inrush current of 5A for 20ms and a no-load leakage current below 1.8mA. ### M12/M18/M30 Metal-Housing Capacitive Proximity Sensors (Cable Type) URL: https://www.daidisensor.com/products/proximity-sensor/m12-m18-m30-metal-housing-capacitive-proximity-sensors/ M12/M18/M30 nickel-plated metal capacitive proximity sensors with adjustable sensing distance, IP67 rating, and 1.5ms response time for level detection. - Covers M12, M18, and M30 threaded capacitive proximity sensors in a nickel-plated metal, cable-type housing. - Each model has a factory-defined, field-adjustable sensing distance rather than a single fixed trip point. - Offered in flush and non-flush mounting styles, with non-flush models marked by a "T" suffix. - Every model is available in NPN or PNP output, with NO or NC logic, on standard 3-wire DC wiring. ### M18/M30 Capacitive Proximity Sensors with M12 Connector (Plug-in Type) URL: https://www.daidisensor.com/products/proximity-sensor/m18-m30-capacitive-proximity-sensors-with-m12-connector/ M18/M30 capacitive proximity sensors with a detachable M12, 4-pin connector, 2-5mm to 2-30mm adjustable sensing distance, IP67, 1.5ms response, NPN/PNP NO/NC. - This series covers M18 and M30 threaded capacitive proximity sensors terminated in a detachable M12, 4-pin connector instead of a fixed cable. - Adjustable sensing distances range from 2-5mm (M18 flush, R1805) to 2-30mm (M30 non-flush, R3030T) across the eight models in this series. - The housing is nickel-plated metal, sealed to IP67, per the manufacturer's selection table. - Response time is 1.5ms and the stated overload current protection point is 240mA across both M18 and M30 sizes. ### M18 / M30 Inductive Proximity Sensors (35mm & 55mm Body Length) URL: https://www.daidisensor.com/products/proximity-sensor/m18-m30-inductive-proximity-sensors/ M18/M30 inductive proximity sensors in 35mm short or 55mm standard body, flush and non-flush, 5-40mm sensing distance, IP67, NPN/PNP, NO/NC, 10-30VDC 3-wire. - The M18/M30 inductive proximity sensor series covers sensing distances from 5mm (M18 flush) up to 40mm (M30 non-flush). - Each thread size - M18 and M30 - is available in a 35mm short body or a 55mm standard body. - All models operate on 10-30VDC, 3-wire DC wiring, with NPN or PNP output in normally-open or normally-closed configuration. - Response time ranges from 0.2ms to 2ms and switching frequency ranges from 80Hz to 1KHz across the series, depending on sensing distance and mounting type. ### M3/M4/M5 Short-Body Separate-Amplifier Inductive Proximity Switches (15mm) URL: https://www.daidisensor.com/products/proximity-sensor/m3-m4-m5-short-body-separate-amplifier-inductive-proximity-switches/ M3/M4/M5 short-body (15mm) unthreaded inductive proximity switches: D3/D4/M5 diameters, 0.6-1.5mm sensing distance, NPN/PNP output, NO/NC, 3-wire DC wiring. - The M3/M4/M5 short-body inductive proximity switch series has a 15mm body length, shorter than the same brand's standard 25mm unthreaded M3/M4 and threaded M5 proximity switches. - M3 short-body proximity switches are available with 0.6mm, 0.8mm, or 1.0mm sensing distance. - M4 and M5 short-body proximity switches are available with 0.8mm, 1.0mm, 1.2mm, or 1.5mm sensing distance. - Every diameter and sensing distance in this series is offered in both NPN and PNP output, each with NO (normally-open) or NC (normally-closed) logic. ### M3 / M4 Non-Threaded (Thread-less) Inductive Proximity Switches URL: https://www.daidisensor.com/products/proximity-sensor/m3-m4-non-threaded-inductive-proximity-switches/ M3/M4 non-threaded inductive proximity switches: D3/D4mm barrel, 0.6-1.5mm sensing distance, NPN/PNP NO/NC output, 10-30VDC 3-wire, IP67, -25C to +70C. - The M3 non-threaded inductive proximity switch has an outer diameter of 3mm and an overall length of 25mm, with a 0.6mm, 0.8mm, or 1.0mm sensing distance. - The M4 non-threaded inductive proximity switch (D4x25mm) offers 0.8mm, 1.0mm, 1.2mm, or 1.5mm sensing distance. - Both the M3 and M4 non-threaded proximity switch versions are rated IP67 with an operating temperature range of -25C to +70C. - The series is available in NPN or PNP DC 3-wire output, each in normally-open (NO) or normally-closed (NC) configuration. ### M8 Capacitive Proximity Switch (Metal Housing, Cable Type) URL: https://www.daidisensor.com/products/proximity-sensor/m8-capacitive-proximity-switch/ M8 capacitive proximity switch detects metal and non-metal targets (liquids, powders, wood, glass, plastic) at 1mm/2mm range, IP67, M8x45mm, NPN/PNP 10-30VDC. - The M8 capacitive proximity switch offers a 1mm sensing distance in flush mounting and 2mm in non-flush mounting. - This M8 capacitive proximity switch measures M8x45mm and uses a nickel-plated brass metal housing rated IP67. - The sensor operates on 10-30VDC and provides NPN or PNP output in normally open (NO) or normally closed (NC) configuration. - Response time is 1.5ms with a switching frequency of 100Hz. ### M8 Inductive Proximity Sensors (Short/Flush, Y-Type, 35mm, 45mm) URL: https://www.daidisensor.com/products/proximity-sensor/m8-inductive-proximity-sensors/ M8x1 inductive proximity sensors in straight, Y-type, 35mm and 45mm bodies. Sensing 1-6mm, IP67, -25 to +70C, NPN/PNP NO/NC 3-wire DC, 0.1ms response time. - The M8 inductive proximity sensor family (18mm, Y-type, 35mm, 45mm bodies) offers sensing distances from 1mm (flush) to 6mm (non-flush, 45mm body). - All variants in this M8 sensor family are rated IP67 with an operating temperature range of -25°C to +70°C. - Response time is 0.1ms on the 18mm, Y-type, and short-range taps of the 35mm/45mm M8 proximity sensors. - Each M8 sensing-distance variant is available in NPN or PNP output with NO (normally open) or NC (normally closed) switching logic. ### M8/M12 Capacitive Proximity Switch with Connector (Plug-in, Aviation Connector) URL: https://www.daidisensor.com/products/proximity-sensor/m8-m12-capacitive-proximity-switch-with-connector/ M8/M12 capacitive proximity switch with M8 3-pin or M12 4-pin aviation connector, 10-30VDC, NPN/PNP NO/NC, sensing 1mm to 1-6mm adjustable, IP65/IP67. - The M8 capacitive proximity switch (M8 connector version) offers a 1mm±10% sensing distance in flush mounting and 2mm±10% in non-flush mounting. - The M12 capacitive proximity switch (M12 connector version) has a potentiometer-adjustable sensing distance of 1-2mm, 1-3mm, 1-4mm, or 1-6mm depending on model. - The M8 series uses an M8 3-pin plug-in connector; the M12 series uses an M12 4-pin plug-in connector. - The M8 housing is stainless steel (M8x1 thread, 60mm body length); the M12 housing is nickel-plated brass (M12x1 thread, 69mm body length). ### M8/M12/M18/M30 DC 2-Wire Inductive Proximity Sensors URL: https://www.daidisensor.com/products/proximity-sensor/m8-m12-m18-m30-dc-2-wire-inductive-proximity-sensors/ M8/M12/M18/M30 2-wire DC inductive proximity sensors: 10-30VDC, IP67, 1-25mm sensing distance, flush/non-flush mount, NO/NC output, -25C to +70C. - This inductive proximity sensor series is available in four barrel sizes — M8, M12, M18, and M30 — each offered in flush and non-flush mount versions. - The DC 2-wire versions in this series operate on 10-30VDC and carry an IP67 protection rating. - Sensing distance across the series ranges from 1mm (M8, flush mount) to 25mm (M30, non-flush mount). - Each model is available with either normally-open (D1) or normally-closed (D2) output. ### Q08 Series Square Inductive Proximity Sensor (Q082.5T / Q082.5F) URL: https://www.daidisensor.com/products/proximity-sensor/q08-series-square-inductive-proximity-sensor/ Q08 series square inductive proximity sensor (Q082.5T/Q082.5F): 8x8mm body, 2.5mm sensing distance, NPN/PNP NO/NC DC 3-wire output for tight machine spaces. - The Q08 series square inductive proximity sensor has a body cross-section of 8mm x 8mm. - The Q082.5T variant uses side-sensing (detection from the side face) with a body length of 23mm. - The Q082.5F variant uses top-sensing (detection from the top face) with a body length of 25mm. - Both Q082.5T and Q082.5F are rated at a 2.5mm sensing distance. ### Q10 Series Square Inductive Proximity Switch (Q102.5 / Q104) URL: https://www.daidisensor.com/products/proximity-sensor/q10-series-square-inductive-proximity-switch/ Q10 series (Q102.5/Q104) square inductive proximity switches: 2.5mm or 4mm side-face sensing, NPN/PNP NO/NC output, 10-30VDC, IP67, -25 to +70 C. - The Q102.5 inductive proximity switch has a rated sensing distance of 2.5mm; the Q104 variant has a rated sensing distance of 4mm. - Both Q102.5 and Q104 use a side-face (lateral) sensing element rather than a front-facing sensing tip. - The Q10 series body measures approximately 10mm wide by 27-30mm long, with a thickness of 6mm (Q102.5, ABS housing) or 6.5mm (Q104, PBT housing). - The Q10 series is a 3-wire DC inductive proximity switch operating on 10-30VDC, available in NPN or PNP output with normally open (NO) or normally closed (NC) logic. ### Q17 / Q18C Square Inductive Proximity Sensor URL: https://www.daidisensor.com/products/proximity-sensor/q17-q18c-square-inductive-proximity-sensor/ Q17/Q18C square inductive proximity sensors: 5mm or 8mm sensing distance, NPN/PNP output, NO/NC logic, 3-wire DC, PBT housing for metal target detection. - The Q17 and Q18C are square-body inductive proximity switches offered with 5mm or 8mm sensing distance. - Both Q17 and Q18C series provide NPN and PNP output types with NO (normally open) and NC (normally closed) switching logic, selectable via the model code. - The Q17 housing measures 17 x 17 x 28 mm and includes a front-mounted LED status indicator. - Q17 and Q18C use a PBT plastic housing per the manufacturer's selection chart. ### Q20 Square Capacitive Proximity Switch URL: https://www.daidisensor.com/products/proximity-sensor/q20-square-capacitive-proximity-switch/ Q20 square capacitive proximity switch: 10mm sensing distance, NPN/PNP output, NO/NC logic, flush or non-flush mounting, for non-metal target detection. - The Q20 capacitive proximity switch has a fixed sensing distance of 10 mm. - The Q20 series is available in NPN and PNP output types, each with normally-open (NO) and normally-closed (NC) contact logic. - The Q20 uses a square housing and a 3-wire DC connection. - The Q2010N1 and Q2010P1 models are flush-mountable, while the Q2010N2T and Q2010P2T models use a non-flush mounting design. ### Q25 / Q30 / Q40 Square Inductive Proximity Sensors URL: https://www.daidisensor.com/products/proximity-sensor/q25-q30-q40-square-inductive-proximity-sensors/ Q25, Q30 and Q40 square inductive proximity sensors: 10-20mm sensing distance, 10-30VDC 3-wire NPN/PNP NO/NC output, IP67 PC housing, up to 500Hz switching. - The Q25, Q30 and Q40 are square-body inductive proximity sensors with sensing distances of 10-15mm (Q25/Q30) and 15-20mm (Q40). - Each Q25/Q30/Q40 model is available with NPN or PNP output, in normally-open (N1/P1) or normally-closed (N2/P2) configuration. - The sensors are powered by 10-30VDC via a 3-wire DC connection and are rated IP67. - Housing dimensions are 25x25x35mm (Q25), 30x30x38mm (Q30), and 40x40x53mm (Q40), with a PC plastic housing. ### RS Series M12/M18/M30 Capacitive Proximity Sensor (ABS Plastic Housing) URL: https://www.daidisensor.com/products/proximity-sensor/rs-series-m12-m18-m30-capacitive-proximity-sensor/ RS series capacitive proximity sensor: M12/M18/M30 threads, ABS plastic housing, NPN/PNP output, NO/NC logic, flush and non-flush mount, 3-wire DC. - The RS series capacitive proximity sensor is available in three threaded sizes — M12, M18, and M30 — with an ABS plastic housing. - Each RS series thread size offers NPN and PNP output, each in normally-open (NO) and normally-closed (NC) switching logic. - The RS series is offered in flush-mount (standard) and non-flush-mount (T-suffix) body styles. - The RS series is wired as a 3-wire DC sensor. ### SN04 / TL-W5E1 Series Square Inductive Proximity Switch URL: https://www.daidisensor.com/products/proximity-sensor/sn04-tl-w5e1-series-square-inductive-proximity-switch/ SN04 and TL-W5E1 series square inductive proximity switches: 4-7mm sensing distance, NPN/PNP output, NO/NC logic, DC12-24V supply for PLC panels. - The SN04 inductive proximity switch has an 18x18x34mm square body and a rated sensing distance of 4mm. - The TL-W5 series offers two sensing distances in the same body style: 5mm (E suffix) and 7mm (F suffix). - TL-W5E1 measures 42x25x10mm with two Phi3.5mm mounting holes and a 50mm output cable. - The SN04/TL-W5 family is available in both NPN and PNP output types, with suffix '1' for normally-open (NO) and suffix '2' for normally-closed (NC) logic. ## safety-relay Category URL: https://www.daidisensor.com/products/safety-relay/ ### Safety Relay Modules for E-Stop, Light Curtain and Door Circuits A **safety relay module** evaluates a dual-channel signal from an emergency-stop device, safety light curtain, safety door interlock or two-hand control and uses forcibly guided contacts to interrupt hazardous machine functions. It is the evaluation stage between the field safety device and the machine contactors — not the sensor, PLC or contactor itself. DAIDISIKE lists two modules here. Compare the [DA31 e-stop safety relay](/products/safety-relay/da31-emergency-stop-safety-relay-module/) with the [DQSRN safety relay module](/products/safety-relay/dqsrn-safety-relay-module/) using the actual input version, terminal arrangement and current drawing. DQSRN's confirmed drawing gives a 22.5 mm housing width; the older 45 mm entry is not the current selection value. Figure context: Field safety device → dual-channel evaluation → forcibly guided contacts → machine contactors; status can be reported separately. ### DA31 vs DQSRN Safety Relay Module Compare the exact shipped module and input/output documentation, not just a catalogue summary. DQSRN's current instructions and drawing establish a 22.5 mm housing width and describe manual or automatic reset according to the selected circuit. Its release response is listed below 30 ms; a different timing label in a product photograph must not be substituted for that release specification. Published attribute | DA31 | DQSRN Housing width | 22.6 mm | 22.5 mm per confirmed drawing Dual-channel input | PNP or NPN | see product input-mode specification Input modes | e-stop / OSSD / door / two-hand | e-stop / OSSD / door / two-hand Relay contacts | 3 N.O. + 1 N.C. forcibly guided | 3 N.O. + 1 N.C. forcibly guided Separate PLC status output | transistor signaling output <500 mA / 24 VDC | not listed as a separate transistor output Response | <30 ms | Release response <30 ms per instruction table Manual reset / automatic reset / EDM | Verify current DA31 circuit documentation | Manual/automatic reset per selected circuit; EDM not claimed ### Select by Input Device and OSSD Compatibility For an e-stop circuit, confirm that the device channels and selected relay input mode form the required safety function; the [DA31 e-stop safety relay](/products/safety-relay/da31-emergency-stop-safety-relay-module/) page contains its exact input and output selection. For an OSSD light curtain, choose the published OSSD input mode and verify output polarity and test-pulse compatibility from the exact device documents. For a guard switch, verify whether the field device outputs mechanical contacts, NPN or PNP transistor channels. DA31 is also the catalogue option for a safety relay module with PLC status output: its separate transistor signaling output can report machine run/stop status to a PLC without consuming a safety contact. This is status reporting, not programmable safety logic. The [DQSRN safety relay module](/products/safety-relay/dqsrn-safety-relay-module/) is the alternative when its documented housing and terminal arrangement fit the panel. ### What a Safety Relay Does — and Does Not Do The relay evaluates the selected safety input and switches its safety contacts. It does not sense a person, read a door mechanically, or replace the output contactors. It also does not make the whole circuit Category 4 / PL e / SIL 3 by itself: the achieved level belongs to the complete safety function, including the input device, logic, output elements, architecture and validation. Neither DA31 nor DQSRN is presented here as a programmable safety relay or safety PLC. If the application needs several independent zones, configurable logic or networked diagnostics, do not force a single-function relay into that role. For a model check, send the field safety device, output type, required number of safety contacts, load/contactors and available DIN-rail width via the [inquiry form](/contact/). ### Safety Evaluation or Programmable Process Control? Keep the safety stop function separate from ordinary programmable automation. If the purchase is for timers, Modbus I/O or compact programmable sequencing, compare the [relay and control module catalogue](/products/relay-module/). Those modules are not substitutes for a safety relay or safety PLC. For light-curtain pairing, use the [light-curtain configuration guide](/guides/how-to-choose-a-safety-light-curtain/) to record the output version, then check the exact relay input documentation. Send the sensor code and controller requirement together rather than ordering each independently. ### Category FAQ Q: What does a safety relay module do? A: It evaluates a safety input and changes forcibly guided output contacts so downstream contactors can remove power from hazardous machine functions. Q: Which safety relay is suitable for a light curtain OSSD output? A: DA31 and DQSRN both list an OSSD input mode. Confirm the exact light-curtain output polarity, test pulses and circuit documentation before final wiring. Q: Can DA31 send status to a PLC? A: Yes. Its published specification includes a separate transistor signaling output below 500 mA / 24 VDC for status reporting. Q: Can DA31 execute configurable safety logic? A: No. It uses DIP switches to select one of four published input modes; it is not presented as a programmable logic controller. Q: Do DA31 or DQSRN include manual reset, automatic reset or EDM? A: DQSRN supports manual or automatic reset as described in the confirmed current instructions; follow the circuit for the selected module version. EDM is not claimed without explicit supporting documentation. For DA31, verify its own current circuit and mode information separately rather than transferring DQSRN functions. Q: Does a Cat.4 / PL e safety relay make the complete machine circuit PL e? A: Not automatically. The complete safety function must be designed and validated to the required level, and its result is limited by the architecture and every component in the chain. Q: What is the main selection difference between DA31 and DQSRN? A: Compare input type, contact arrangement, status output and circuit functions rather than housing width alone. DQSRN's current drawing specifies 22.5 mm, and its instructions describe manual/automatic reset by circuit. Use each module's own current dimensional and wiring document before panel layout. ### DA31 Emergency-Stop Safety Relay Module URL: https://www.daidisensor.com/products/safety-relay/da31-emergency-stop-safety-relay-module/ DA31 emergency-stop safety relay module: ultra-slim 22.6 mm width, Category 4/PL e/SIL 3, PNP/NPN dual input, <30 ms response, AC-1 6A/250VAC contacts. - The DA31 emergency-stop safety relay module measures 112 × 99.5 × 22.6 mm, with a housing width of 22.6 mm. - DA31 provides dual-channel safety input compatible with both PNP and NPN signal types. - DA31's output stage combines 3 normally-open and 1 normally-closed forcibly guided relay contacts with a separate solid-state signaling output rated below 500 mA / 24 VDC. - DA31 offers four DIP-switch selectable safety input modes: emergency stop, safety light curtain OSSD, safety door interlock, and two-hand control. ### How DA31 Fits Between the Safety Device and PLC The field device—an e-stop, OSSD light curtain, guard interlock or two-hand control—provides the dual-channel input. DA31 evaluates the selected input mode and switches its forcibly guided relay contacts for the machine contactor circuit. A separate transistor signaling output can report status to a standard PLC input without consuming one of the safety contacts. That PLC connection is status reporting only. DA31 is a DIP-switch-selected **safety relay module with PLC status output**; it is not a programmable safety relay and the PLC does not replace the module's safety evaluation. Figure context: Safety path and status path stay separate: contacts control the safety circuit; the transistor output reports status. ### Select the DA31 Input Mode by Field Device Published DA31 mode | Field device | What to confirm Emergency stop | dual-channel e-stop device | channel/contact arrangement and complete stop circuit Safety light curtain OSSD | OSSD-output safety light curtain | PNP/NPN signal type and device documentation Safety door interlock | dual-channel guard switch | mechanical contact or transistor signal compatibility Two-hand control | two-hand operating device | device timing and full safety-function validation Only one published input mode is selected for the module's safety function. If the machine needs several independent zones or programmable logic, use an architecture designed for that job instead of treating DA31 as a safety PLC. Compare both catalogue modules on the [safety relay category page](/products/safety-relay/). ### DQSRN Safety Relay Module URL: https://www.daidisensor.com/products/safety-relay/dqsrn-safety-relay-module/ DQSRN safety relay: manual/automatic reset, 3NO+1NC contacts, release response <30 ms, 117x100x22.5 mm, 24V DC. Housing IP30, terminals IP20; EDM not claimed. - DQSRN monitors compatible dual-channel transistor safety signals or two N.C. switch signals with the prescribed peripheral circuit. Match input polarity and wiring to the exact supplied configuration; do not assume one setting covers every input device. - The manufacturer states Category 4 / PL e per EN ISO 13849-1 and SIL 3 per IEC 61508. Certification scope and the achieved rating of the complete safety circuit require verification. - DQSRN's output stage provides 3 normally-open safety contacts and 1 normally-closed auxiliary contact, using a forcibly guided (positively driven) contact design. - The confirmed parameter table lists AgSnO2 contacts with 0.2 µm gold plating, minimum load 10 mA/5 V, AC-1 6A/250VAC and AC-15 4A/240VAC. The 12A maximum is distributed across all safety output contacts, not a per-contact rating. ## safety-light-curtain Category URL: https://www.daidisensor.com/products/safety-light-curtain/ ### 17 Series, One Decision Path Compare seventeen light-curtain series by the exact configuration you need to order. Personnel-protection equipment must have documented detection capability, safety outputs and an applicable safety rating. This existing catalogue also contains the [DD / DDOF single-sided area sensors](/products/safety-light-curtain/dd-diffuse-reflection-area-light-curtain/): they are object-detection products, not personnel-protection devices, despite their position in this directory. Start with the required function and evidence, then compare environment, minimum detectable object, field height, operating span, housing and output. Keep the selected model code together with its drawings and instructions; a family name or a small beam pitch does not establish a safety rating. Figure context: Selection prompts, not a safety approval: verify each shortlisted configuration before ordering. ### Compare Beam Pitch and Verified Detection Capability Separately Beam pitch is the distance between adjacent optical axes. Detection capability is the smallest object the selected configuration is specified to detect. They are not interchangeable: DQT4 lists 7.5 mm pitch with 14 mm detection, while DQC lists 10 mm pitch with 18 mm detection. Never enter pitch in a safety-distance calculation that calls for object detection capability. Use the product specification for the exact pitch, beam count and field height. Do not infer finger protection from a 10 mm pitch, or use the category table as proof of the complete machine safety function. Configuration to check | Beam pitch | Published detection capability | Purchase check [DQT4](/products/safety-light-curtain/dqt4-type-4-safety-light-curtain/) fine-pitch option | 7.5 mm | 14 mm | Exact model, field height, output and applicable documentation [DQT4](/products/safety-light-curtain/dqt4-type-4-safety-light-curtain/) other pitches | 15 / 30 mm | 21 / 36 mm respectively | Do not substitute pitch for detection capability [DQC](/products/safety-light-curtain/dqc-general-safety-light-curtain/) fine-pitch options | 10 / 14 mm | 18 / 22 mm respectively | These figures do not establish 14 mm finger detection MQ, JER, MK and other listed series | See exact order-code table | Verify the applicable model specification | Do not infer Type / PL or detection capability from directory membership Figure context: Compare the published detection capability, not beam pitch alone. Mounting distance also depends on the full machine stopping function. ### Pick by Housing: Ultra-Thin, Mini, and Zero Blind Zone On retrofits, the mounting slot often chooses the series before any optical spec gets a vote. The DQB and its optically-synchronised twin DQBT run a 15 × 30 mm side-emitting profile that drops into an 18 mm gap between guide rails; the DQZ does the same trick front-emitting at 17.2 × 30 mm; the MK squeezes a full **light curtain sensor** into 25 × 23 mm for bench-top machines; the new [MQ Essence Edition](/products/safety-light-curtain/mq-essence-safety-light-curtain/) packs optical synchronisation — no wire at all between transmitter and receiver — into a 29 × 30 mm body with M12 plug-and-play cables. The DQO's speciality is its ends: first and last beams sit just 6.75 mm from the housing tips, so the protected field can start almost flush against a machine shoulder — the answer when a standard curtain's end blind zone would leave a reachable gap. The cross-sections below are drawn to a common scale. If your slot is the constraint, start here and let the profile pick the family; the optical specs inside each family then follow the resolution logic above. Figure context: Drawn to one scale: when the slot is fixed, the profile chooses the series for you. ### Pick by Span and Coverage: 3 m Standard to 40 m, and Mirror-Folded Perimeters Standard optical ranges run 0.3–3 m or 0.3–6 m, which covers most feed openings. Long beds and transfer lines step up to the DQA and DQT long-range grades, whose detection-distance classes reach 0.3–40 m; the DQT additionally scales to 72 beams for tall access ways. Perimeter work changes the geometry rather than the range: the DQSA area-protection system takes one transmitter/receiver pair plus one to three corner mirrors and folds the beams around two, three or four sides of a robot cell — protective heights to 3920 mm at 40 or 80 mm pitch, with one wiring point instead of four. For an **industrial safety light curtain** layout around a full cell, that mirror trick is routinely the difference between a tidy installation and a cable-tray project. ### Harsh Environments: Waterproof and Explosion-Proof DQR and DQRF provide different published ingress-protection options, but IP65 or IP68 alone is not approval for a cleaning process. State water pressure, temperature, chemicals, connector exposure and mounting conditions when requesting the exact configuration. For an FB special-order enclosure, provide the hazardous-area classification and request the applicable evidence for the complete assembled configuration; an enclosure alone does not establish personnel-protection or explosion-protection approval for every optical core. ### Outputs and Getting Into the Stop Circuit NPN, PNP, relay contacts and OSSD are not interchangeable labels. Output arrangements, test pulses, supply and current limits vary by configuration. The [light-curtain selection guide](/guides/how-to-choose-a-safety-light-curtain/) identifies what to request before comparing models; use the exact manual for the electrical connection. For a safety function, compare the field device with the [safety relay modules](/products/safety-relay/) or an appropriate safety controller. Check input type, pulse compatibility, reset and external-device monitoring requirements at system level. Neither a shared brand nor a directory link proves that two devices form a validated combination. Full wiring diagrams for every output type — including channel-by-channel drawings and reset options — are maintained in the DAIDISIKE engineering library on [fsddsk.com](https://www.fsddsk.com/safety-light-barrier-wiring-diagram); this page deliberately stays above pin level. Figure context: Conceptual signal path only. Total stopping time includes the sensor, logic, output elements and machine; it is not a fixed 10–20 ms value. ### Type Ratings, Stated Honestly There is no category-wide Type 4 guarantee. Compare the exact model and output configuration against its applicable instructions, declaration and certificate scope. A design-description sentence is not a substitute for that evidence. MQ, JER and MK must not inherit a rating from neighbouring products; DD and DDOF remain detection-only. Keep the required safety function separate from your procurement evidence. The [Type 2 and Type 4 guide](/guides/type-2-vs-type-4-safety-light-curtains/) explains which model-specific documents and output details to request without assigning a rating from price or housing size. ### Safety, Measuring, or Press-Brake? Don't Buy the Wrong Family Light curtains may look similar while performing different jobs. [Measuring light curtains](/products/measuring-light-curtain/) provide process measurements or object detection and are not personnel-protection substitutes. This directory retains a clearly identified DD/DDOF detection-only family for existing visitors; select a safety-rated configuration when safeguarding people. For press tooling, review the [press and press-brake protection options](/products/press-brake-protection/) with the machine integrator. A fixed light curtain and ram-mounted laser protection address different layouts; suitability depends on the machine, task, stopping performance and applicable safety requirements, not an unconditional rule that one can never be used. Figure context: Three duties, three families: fine-pitch feed openings, mirror-folded perimeters, washdown housings. Send the machine task, opening dimensions, required detection capability, controller details and requested evidence through the [inquiry form](/contact/). Confirm the complete pair, cables and brackets on the quotation. ### Category FAQ Q: What is a safety light curtain and how does it work? A: A safety light curtain uses an emitter and receiver to monitor a protective field. Interruption changes its safety outputs; a suitable control system and machine stopping elements perform the protective stop. Model-specific documentation and complete-machine validation are necessary. Q: What is the difference between a light curtain sensor and a safety light curtain? A: Construction is similar; duty is not. Detection and measuring grids report data and carry no safety rating — ours live in the [measuring light curtain category](/products/measuring-light-curtain/). A safety light curtain is engineered for personnel protection with self-monitored safety outputs and is the only kind that belongs in a protective stop circuit. Q: How is the price of a safety light curtain determined? A: Compare field height, operating span, verified detection capability, output version, housing, cables, brackets and order quantity. Pitch and detection capability are separate specification fields. Request a quotation for a complete configuration rather than assuming one price covers every option. Q: What HS code do safety light curtains ship under? A: Tariff classification varies with the destination country's schedule, so we do not print a single code here. The commercial invoice and packing documents we issue carry the classification our export declarations use, and we can provide it before you order so your broker can pre-confirm the import side. Q: Which series should I look at first? A: Start with the required function and supporting documentation. Then compare DQC or MQ for their listed mechanical and electrical options, DQT4 for its documented detection configurations, DQB/DQZ for narrow housings, DQA/DQT for span options, and DQSA for mirror layouts. JER/MK/MQ need model-specific rating verification; DD/DDOF are not personnel-protection devices. ### DCE Automation Safety Light Curtain URL: https://www.daidisensor.com/products/safety-light-curtain/dce-automation-safety-light-curtain/ DCE safety light curtain: 30x30 mm housing, 10/20/30/40 mm pitch, up to 72 beams, protected height to 2840 mm, 0.3-6 m range, NPN/PNP, IP65. Type 4 / Cat. 4 design. - DCE is a through-beam transmitter/receiver light curtain. The catalogue states Type 4 / Category 4 (PLd) and cites IEC 61496-1/-3, EN 61496-3:2019, EN 13849-1:2015 and TUV/UL testing. Exact safety rating, standard-part applicability and certificate scope require confirmation; catalogue wording alone is not proof of certification. - DCE offers four beam pitches -- 10, 20, 30 and 40 mm. Detection accuracy (minimum detectable object) is printed in the catalog as 18, 28 and 48 mm for the 10/20/40 mm pitches respectively (pitch + 8 mm); the 30 mm pitch's detection-accuracy figure is not printed in the catalog's parameter table. - DCE response time is 15 ms or less, and it rejects ambient light up to 10,000 lux at an incidence angle of 5 degrees or more; the catalog separately lists 3,000 lux (incandescent) and 10,000 lux (sunlight) tolerance measured at the receiver face. - DCE sensing distance is 0.3-3 m (model-code letter A) or 0.3-6 m (letter B). Its listed housing cross-section is 30 x 30 mm; compare selected series using their current dimension drawings rather than an unverified cross-series size claim. ### DD / DDOF Single-Sided Area Light Curtain URL: https://www.daidisensor.com/products/safety-light-curtain/dd-diffuse-reflection-area-light-curtain/ Buy the right single-sided area light curtain: DD diffuse models (DD0440-DD5040, to 2000 mm) or DDOF time-of-flight models (DDOF0440-DDOF5040, to 4000 mm, no dead zone, colour-independent). 40 mm pitch, NPN+PNP fitted, factory direct. - Order code is the whole decision: the DDOF prefix buys per-beam time-of-flight ranging (4000 mm, no dead zone, distance window taught with one key), the DD prefix buys diffuse energy sensing (2000 mm, dead zone possible, steps 1-9) - everything mechanical is shared between them. - 48 standard models in total: DDOF0440 through DDOF5040 and DD0440 through DD5040, each series in 24 even-beam tiers from 4 to 50 beams at the fixed 40 mm pitch. - Height mathematics printed on the 2026-08 factory sheet: detection height H = beam count x 40 mm (160-2000 mm), overall housing length L = H + 49 mm (209-2049 mm) - the 49 mm being two 12 mm end caps plus the mounting allowance. - The DDOF's background suppression is geometric, not optical trickery: each beam measures the distance to whatever reflects it, and anything outside the taught window - including the wall behind the line - is simply not reported. ### DQA Long-distance Safety Light Curtain URL: https://www.daidisensor.com/products/safety-light-curtain/dqa-long-distance-safety-light-curtain/ DQA long-range through-beam safety light curtain: 10-200 mm pitch, 4-32 beams, 0.3-40 m range, response <=15 ms, IP65, NPN/PNP/relay. Type 4 / Cat. 4 design. - The DQA is designed to the Type 4 architecture of IEC 61496-1/-3 and to Category 4 of ISO 13849-1, as stated in the DAIDISIKE light-curtain catalog. Certification documents are available on request. - The DQA is covered by TÜV SÜD Attestation of Conformity No. E8A 104143 0001 for electromagnetic compatibility (EU EMC Directive 2014/30/EU), tested to EN 61000-6-2:2005 and EN 61000-6-4:2007/A1:2011. - The DQA sensing distance is selectable by model code across eight steps — 0.3-3 m, 0.3-6 m, 0.3-10 m, 0.3-15 m, 0.3-20 m, 0.3-25 m, 0.3-30 m and 0.3-40 m (codes A to H). - The DQA offers eight beam pitches — 10, 14, 20, 25, 30, 40, 80 and 200 mm — with a corresponding detection accuracy (minimum detectable object) of 18, 22, 28, 33, 38, 48, 88 and 208 mm respectively (pitch + 8 mm). ### DQB Ultra-thin (Side-emitting) Safety Light Curtain URL: https://www.daidisensor.com/products/safety-light-curtain/dqb-ultra-thin-safety-light-curtain/ DQB ultra-thin, side-emitting safety light curtain: 15 x 30 mm cross-section, 20/40 mm pitch, protective height 100-1240 mm, NPN/PNP transistor output. - The DQB safety light curtain has a 30 x 15 mm housing cross-section (x L, the transmitter/receiver length), with the light axes emitting from the 15 mm side face of the housing rather than the front - a side-emitting, ultra-thin design. - DQB's model-code legend and technical parameter table list three light-axis pitches - 10, 20 and 40 mm - with detection accuracy (minimum detectable object) of 18, 28 and 48 mm respectively (pitch + 8 mm); the catalog's populated model list, however, only provides specific model numbers for the 20 mm and 40 mm pitches. - The 20 mm pitch DQB models range from 6 to 32 light axes (protective height 100-620 mm); the 40 mm pitch models range from 4 to 32 light axes (protective height 120-1240 mm), each in steps of 2, with protective height = light axis pitch x (axis count - 1). - DQB uses transistor output - NPN or PNP, normally open or normally closed, selectable by model-code letter (A = NPN NC, B = PNP NC, C = NPN NO, D = PNP NO, default A) - wired via a circular aviation connector with a dedicated cable: 4-core on the transmitter, 5-core on the receiver. ### DQBT Ultra-thin Optical-sync Safety Light Curtain URL: https://www.daidisensor.com/products/safety-light-curtain/dqbt-ultra-thin-optical-sync-safety-light-curtain/ DQBT ultra-thin safety light curtain with optical sync — no sync cable between emitter and receiver. 10/20/40 mm pitch, <=15 ms response, 0.3-3 m, NPN/PNP output. - DQBT's emitter and receiver synchronize via an optical signal instead of a wired sync cable — the catalog's feature list states "采用光同步技术" (optical synchronization technology), and the DQBT wiring diagram shows only local power/output wiring on each side, with no sync wire running between the two towers. - DQBT is offered in three beam pitches per the catalog's own DQBT spec tables: 10 mm, 20 mm and 40 mm. - At 10 mm pitch, DQBT's spec table runs cleanly from an 8-beam unit (DQBT08/10-70, 70 mm protected height) to a 100-beam unit (DQBT100/10-990, 990 mm protected height), in steps of 2 beams. - At 20 mm pitch, the table runs from 6 beams (DQBT06/20-100) up through 198 beams (DQBT198/20-3940); a further row lists 3980 mm protected height (i.e., 200 beams by the series' own H = pitch x (beams-1) formula) but its printed model number reads "DQBT100/20-3980" rather than the expected DQBT200 — the exact top-end model number needs confirming. ### DQC General Safety Light Curtain URL: https://www.daidisensor.com/products/safety-light-curtain/dqc-general-safety-light-curtain/ DQC general-purpose through-beam safety light curtain: 10-200 mm pitch, 4-32 beams, 0.3-6 m range, <=15 ms, IP65, 30x30 mm housing. Type 4 / Cat. 4 design. - The catalogue states a Type 4 / Category 4 design basis and cites IEC 61496-1/-3 and ISO 13849-1. Treat this as a catalogue claim pending the applicable ESPE safety documentation; the separately listed EMC certificate does not establish the personnel-protection function. - The DQC is covered by TÜV SÜD Attestation of Conformity No. E8A 104143 0001 for electromagnetic compatibility (EU EMC Directive 2014/30/EU), tested to EN 61000-6-2:2005 and EN 61000-6-4:2007/A1:2011. - The DQC standard sensing distance is 0.3-3 m (model code A) or 0.3-6 m (model code B); for longer spans the DAIDISIKE DQA long-range curtain covers 0.3-40 m on the same platform. - The DQC offers eight beam pitches — 10, 14, 20, 25, 30, 40, 80 and 200 mm — with a corresponding detection accuracy (minimum detectable object) of 18, 22, 28, 33, 38, 48, 88 and 208 mm (pitch + 8 mm). ### DQE Safety Light Curtain URL: https://www.daidisensor.com/products/safety-light-curtain/dqe-safety-light-curtain/ DQE economical through-beam safety light curtain: 10-200 mm pitch, 4-72 beams, heights to 3800 mm, 0.3-3 m range, <=15 ms, NPN/PNP. Type 4 / Cat. 4 design. - The DQE is designed to the Type 4 architecture of IEC 61496-1/-3 and to Category 4 of ISO 13849-1, as stated in the DAIDISIKE light-curtain catalog. Certification documents are available on request. - The DQE is covered by TÜV SÜD Attestation of Conformity No. E8A 104143 0001 for electromagnetic compatibility (EU EMC Directive 2014/30/EU), tested to EN 61000-6-2:2005 and EN 61000-6-4:2007/A1:2011. - The DQE offers five beam pitches — 10, 20, 40, 80 and 200 mm — with a corresponding detection accuracy (minimum detectable object) of 18, 28, 48, 88 and 208 mm (pitch + 8 mm). - The DQE standard sensing distance is 0.3-3 m; 0.3-6 m is available as model code B, and longer distances are made to order. ### DQO Zero Blind-zone Safety Light Curtain URL: https://www.daidisensor.com/products/safety-light-curtain/dqo-zero-blind-zone-safety-light-curtain/ DQO zero blind-zone safety light curtain: first beam just 6.75 mm from the housing end, 10/20/30 mm pitch, height 90-2130 mm, <=15 ms, IP65, dual NPN/PNP OSSD. - Per the DAIDISIKE catalog's dimension drawing, DQO's first and last active beam positions are offset only 6.75mm (dimensions P and J) from the physical ends of the transmitter/receiver housing, for all three pitch options (10/20/30mm) — the catalog markets this as its “zero blind-zone” (无盲区) design, paired with a per-beam segment indicator LED on the receiver. - DQO is offered in 10mm, 20mm and 30mm beam pitch, with a detection accuracy (minimum detectable object) of 18mm, 28mm and 38mm respectively (pitch + 8mm). - DQO beam count runs from 12 to 70 axes at 10mm pitch, 6 to 72 axes at 20mm pitch, and 4 to 72 axes at 30mm pitch, giving protected heights from 90mm to 2130mm (protected height = pitch x (beam count - 1)). - DQO's response time is <=15ms and the housing is rated IP65, with a 30x28mm transmitter/receiver cross-section. ### DQR / DQRF Waterproof Safety Light Curtain URL: https://www.daidisensor.com/products/safety-light-curtain/dqr-dqrf-waterproof-safety-light-curtain/ DQR/DQRF waterproof safety light curtain: IP65 standard, IP68 enclosure on request, 10-80 mm pitch, height 50-2480 mm, <=15 ms, NPN/PNP. Type 4 / Cat. 4 design. - DQR is rated IP65 as standard; adding the F suffix (DQRF) fits an additional waterproof outer enclosure that the catalog markets as "超强IP68级防水特殊定制" (super-strong IP68-grade waterproof, special customization), raising the rating to IP68 -- this is presented as a special-order upgrade, not a standard off-the-shelf spec. - The DQR is covered by TÜV SÜD Attestation of Conformity No. E8A 104143 0001 for electromagnetic compatibility (EU EMC Directive 2014/30/EU), tested to EN 61000-6-2:2005 and EN 61000-6-4:2007/A1:2011. - The DQR(F) series offers seven beam-pitch options -- 10, 14, 20, 25, 30, 40 and 80 mm -- covering 4 to 32 beams depending on pitch, with protected height spanning 50 mm to 2480 mm across the catalog's full model list. - Detection accuracy (minimum detectable object) is explicitly published for six of the seven pitches: 18 / 22 / 28 / 33 / 38 / 48 mm for the 10 / 14 / 20 / 25 / 30 / 40 mm pitches respectively; the catalog's base parameter table does not state a figure for the 80 mm pitch. ### DQSA Area Protection Light Curtain URL: https://www.daidisensor.com/products/safety-light-curtain/dqsa-area-protection-light-curtain/ DQSA area-protection light curtain: mirror-folded beam guards 2-4 sides of a zone, up to 40 m single-face, 40/80 mm spacing, <=15 ms. Type 4 / Cat. 4 design basis. - DQSA is an area-protection light curtain that uses passive deflection mirrors to fold a single emitter/receiver pair's beam path around 2, 3, or 4 sides of a guarded zone, per the DAIDISIKE catalog. - DQSA's maximum protected distance is capped by face count: up to 40 m for a single face (no mirrors), 20 m for two faces, 15 m for three faces, and 12 m for four faces. - DQSA is available in 40 mm or 80 mm beam spacing, with beam counts from 4 to 72 (40 mm pitch, up to DQSA72/40-2840, a 2840 mm protection height) or 4 to 50 (80 mm pitch, up to DQSA50/80-3920, a 3920 mm protection height). - DQSA's response time is under 15 ms including the controller, and the catalog states its design basis as IEC 61496-1/2, EN 61496-3:2019 Type 4, and EN ISO 13849-1:2015 Category 4 PLd -- design/test basis only; certification documents are available on request. ### DQT Long-distance Safety Light Curtain (Large Beam Count) URL: https://www.daidisensor.com/products/safety-light-curtain/dqt-long-distance-safety-light-curtain/ DQT long-distance safety light curtain: 10/20/40/80 mm pitch, up to 72 beams, height to 2900 mm, 0.3-40 m range, <=15 ms, IP65. Type 4 / Cat. 4 design. - The DQT is designed to the Type 4 architecture of IEC 61496-1/-3 and to Category 4 of ISO 13849-1, as stated in the DAIDISIKE light-curtain catalog. Certification documents are available on request. - The DQT is covered by TÜV SÜD Attestation of Conformity No. E8A 104143 0001 for electromagnetic compatibility (EU EMC Directive 2014/30/EU), tested to EN 61000-6-2:2005 and EN 61000-6-4:2007/A1:2011. - The DQT scales to 72 beam axes — more than double the DQA's 32 — giving protected heights up to about 2840 mm (for example DQT72/40-2840 = 72 beams, 40 mm pitch, 2840 mm protected height). - The DQT offers four beam pitches — 10, 20, 40 and 80 mm — with a corresponding detection accuracy (minimum detectable object) of 18, 28, 48 and 88 mm (pitch + 8 mm). ### DQT4 Type-4 Safety Light Curtain URL: https://www.daidisensor.com/products/safety-light-curtain/dqt4-type-4-safety-light-curtain/ DQT4 safety light curtain designed to Type 4 / Cat. 4 / PLe: 7.5/15/30 mm pitch (14/21/36 mm detection), up to 319 beams, 90-5970 mm protective height, IP65. - DQT4 offers three beam-pitch options — 7.5, 15, and 30 mm — with a corresponding detection accuracy (minimum detectable object) of 14 mm, 21 mm, and 36 mm respectively, per the DAIDISIKE catalogue's product parameter table. - At its finest 7.5 mm beam pitch, DQT4's catalogue-stated detection accuracy is 14 mm (described as finger-level protection), not the 7.5 mm pitch figure itself; the 15 mm pitch gives 21 mm accuracy (hand-level) and the 30 mm pitch gives 36 mm accuracy (arm/body-level). - DQT4 model numbers run from 15 to 319 beams at 7.5 mm pitch (step 8), 8 to 200 beams at 15 mm pitch (step 4), and a standalone 4-beam model plus 8 to 200 beams at 30 mm pitch (step 4) — giving protective heights from 90 mm up to 5970 mm. - The catalogue states DQT4's design basis as PLe and Category 4 per ISO 13849-1 (EN ISO 13849), SIL3, and Type 4 per EN/IEC 61496-1/-2 and GB/T 19436-1/-2. Certification documents are available on request. ### DQZ Ultra-thin (Front-emitting) Safety Light Curtain URL: https://www.daidisensor.com/products/safety-light-curtain/dqz-ultra-thin-safety-light-curtain/ DQZ ultra-thin front-emitting safety light curtain: 17.2 x 30 mm cross-section, 10-80 mm pitch, height 50-2480 mm, 0.3-3 m, <=15 ms, IP65. Type 4 / Cat. 4 design. - The DQZ housing is 17.2 x 30 mm in cross-section with the optical window on the narrow 17.2 mm front face -- the catalog's ultra-thin front-emitting design, intended for mounting depths too shallow for standard-body light curtains. - The DQZ is covered by TÜV SÜD Attestation of Conformity No. E8A 104143 0001 for electromagnetic compatibility (EU EMC Directive 2014/30/EU), tested to EN 61000-6-2:2005 and EN 61000-6-4:2007/A1:2011. - DQZ is offered in seven beam pitches -- 10, 14, 20, 25, 30, 40 and 80 mm -- with actual minimum-object detection checked separately rather than inferred from a body-part label. - Detection accuracy (minimum detectable object) is beam pitch + 8 mm for the 10-40 mm pitches -- 18, 22, 28, 33, 38 and 48 mm respectively, per the catalog's technical-parameter table. The catalog's parameter table does not separately tabulate this figure for the 80 mm pitch. ### Explosion-proof Safety Light Curtain (Custom / FB Series) URL: https://www.daidisensor.com/products/safety-light-curtain/explosion-proof-safety-light-curtain-custom/ DAIDISIKE FB-series explosion-proof light curtains: GB3836-2010 enclosure, Ex nR IIC T6 Gc, Ex tb IIIC T80°C, custom-built to your on-site curtain model. - Enclosure engineered to GB3836-2010, marked Ex nR IIC T6 Gc, Ex tb IIIC T80°C. - Explosion-proof housing cross-section: 80mm x 80mm, drilling position tolerance ±0.5mm. - Cable entry: G1/2 / NPT1/2 (DN15, 4-fen) gland, accepts cable OD 7-10mm; ships with a 2m explosion-proof flexible conduit. - Sealing rubber: oil-resistant, corrosion-resistant national-standard RTY-III type. ### JER Economical Safety Light Curtain (Optical Synchronization) URL: https://www.daidisensor.com/products/safety-light-curtain/jer-economical-safety-light-curtain/ JER economical safety light curtain with optical sync (no sync cable): 10/14/20/40 mm pitch, up to 200 beams, height to 7960 mm, <=15 ms, IP65, NPN/PNP output. - The JER series synchronizes optically between transmitter and receiver (光同步技术) — there is no interconnecting sync cable to run between the two bars, which the catalog says simplifies wiring and cuts installation time. - JER's beam pitch comes in four steps — 10, 14, 20 and 40 mm — each with a corresponding detection accuracy (minimum detectable object) of 18, 22, 28 and 48 mm respectively (pitch + 8 mm). - JER's protected height equals beam pitch x (number of beams - 1); the catalog's model list runs from 70 mm (10 mm pitch, 8 beams) up to 7960 mm (40 mm pitch, 200 beams), with the footnote that beam count can be special-ordered up to 200 on any pitch. - JER's response time is <=15 ms, it rejects ambient light up to 10,000 lux at an incidence angle of >=5 degrees, and the catalog states it shields about 99% of interference signals (electromagnetic noise, strobe lighting, welding arc light). ### MK Mini Economical Safety Light Curtain URL: https://www.daidisensor.com/products/safety-light-curtain/mk-mini-economical-safety-light-curtain/ MK Mini economical safety light curtain: 25 x 23 mm housing, 10-40 mm pitch, 18-48 mm detection accuracy, up to 200 beams, height to 7960 mm, <=15 ms, NPN/PNP. - The MK Mini Economical Safety Light Curtain has a housing cross-section of 25 x 23 mm (transmitter/receiver), per the catalog's outline-dimension drawing and technical parameter table. - MK offers four beam pitches -- 10, 14, 20 and 40 mm -- with a corresponding detection accuracy (minimum detectable object) of 18, 22, 28 and 48 mm respectively (pitch + 8 mm). - MK's catalogue states a 0.3-3 m default and a 0.3-6 m special-order option. The legacy 30-3000 / 30-6000 mm entries are not equivalent at the lower limit: 0.3 m is 300 mm. Obtain the confirmed minimum distance for the actual order. - MK response time is <=15 ms, and it tolerates ambient light up to 10,000 lux at an incidence angle of 5 degrees or more (3,000 lux incandescent / 10,000 lux sunlight measured at the receiver face). ### MQ Essence Edition Safety Light Curtain URL: https://www.daidisensor.com/products/safety-light-curtain/mq-essence-safety-light-curtain/ MQ Essence Edition safety light curtain: 29×30 mm profile, ≤10 ms response, 10/20/40 mm pitch, 4–256 beams, 0.2–7 m range, optical sync with no sync wire, IP65, TUV/CE. - TUV / CE certified — certification covers product design and manufacturing process (per the series manual; ask for the certificate scope for your conformity file) - Response time ≤ 10 ms from beam interruption to output state change - 29 × 30 mm extruded-aluminium cross-section — one of the slimmest formats in its class - Beam pitch 10 / 20 / 40 mm → minimum detectable object Φ15 / Φ25 / Φ45 mm ## slot-sensor Category URL: https://www.daidisensor.com/products/slot-sensor/ ### Choose the Slot Opening and Mounting Before Output Logic A slot sensor contains opposing optical elements in one body. Compare slot width, slot depth, target path, bracket access and connector orientation before choosing output logic. The nominal slot size is not a guarantee that every small or transparent target can be detected. ### Compare the Configuration Paths Required task | Existing product page | What to confirm Wide opening for a passing target | [DD-303N / DD-403N wide-slot options](/products/slot-sensor/dd-303n-dd-403n-wide-slot-photoelectric-sensor/) | Check the actual target clearance and sensing position. Compact slot installation | [DD-L25/45 micro-slot family](/products/slot-sensor/dd-l25-45-series-micro-slot-photoelectric-sensor/) | Compare mounting hole position, opening and cable exit. Connector-based installation | [DD-670 pin/plug-in options](/products/slot-sensor/dd-670-series-slot-photoelectric-sensor/) | Order the correct mating connection and electrical version. ### A Slot-Sensor Sample Request Purchase input | Information to provide Target and path | Send thickness, opacity, smallest gap, motion direction and speed. Mechanical envelope | Record opening, insertion depth and free space around the body and connector. Control signal | Confirm supply, output type, light-on/dark-on behaviour and receiving input. Use the [NPN/PNP guide](/guides/npn-vs-pnp-outputs-explained/) for current-path selection. For printed registration rather than beam interruption, compare [colour-mark sensors](/products/color-mark-sensor/). Send the application details and required configuration through the [inquiry form](/contact/) so that the quotation identifies the selected equipment and options. ### DD-303N / DD-403N Wide-slot Photoelectric Sensor URL: https://www.daidisensor.com/products/slot-sensor/dd-303n-dd-403n-wide-slot-photoelectric-sensor/ DD-303N / DD-403N wide-slot photoelectric sensors: 13 mm through-beam gap, 2.2×0.5 mm min. detectable object, 0.05 mm hysteresis, NPN output, DC5-24V. - The DD-303N / DD-403N series is a through-beam slot photoelectric sensor with a 13 mm detection gap. - Minimum detectable object size is 2.2×0.5 mm. - Hysteresis (differential travel) is 0.05 mm maximum. - The emitter is a 940 nm GaAs infrared LED. ### DD-670 Series Slot Photoelectric Sensor (Pin/Plug-in Connector Type) URL: https://www.daidisensor.com/products/slot-sensor/dd-670-series-slot-photoelectric-sensor/ DD-670 series plug-in connector slot photoelectric sensor: 5 mm slot (7 mm width), 20 models across 5 housing styles and 4 NPN/PNP output versions. - The DD-670 series is a plug-in connector slot photoelectric sensor with a 5 mm detection slot (7 mm slot width). - DD-670 series output versions are designated N (NPN, Light-ON indicator), P (PNP, Light-ON indicator), NA (NPN, Dark-ON indicator), and R (PNP, Dark-ON indicator). - The DD-670 series operation logic can be set via the connector's (L) terminal: open for Dark-ON, shorted to V+ for Light-ON. - The DD-670 series is available in five housing styles - standard (DD-670), L-type (DD-671), T-type (DD-672), and two close-mounting types (DD-673, DD-674) - for a total of 20 catalog part numbers across four output/indicator versions. ### DD-L25/45 Series Micro-slot (Micro U-shaped) Photoelectric Sensor URL: https://www.daidisensor.com/products/slot-sensor/dd-l25-45-series-micro-slot-photoelectric-sensor/ DD-L25/45 series micro-slot photoelectric sensor: 5 mm detection groove, 0.01 mm repeatability, 0.025 mm hysteresis, IP65, NPN/PNP, 20 models, 10 shapes. - The DD-L25/45 series micro-slot photoelectric sensor has a repeatability within 0.01 mm and hysteresis of 0.025 mm or less. - The DD-L25/45 series detects objects as small as 2 x 0.8 mm through a 5 mm detection groove. - The DD-L25/45 series is available in NPN and PNP outputs, each with selectable NO/NC (Light-ON/Dark-ON) operation, across 5 mounting shapes and 2 body sizes (25 mm and 45 mm), totaling 20 part numbers. - The DD-L25/45 series operates at DC5-24V +/-10% with current consumption under 15 mA and ships as a pre-wired type with a 1 m standard cable. ### EE-SX67 Series Slot-type Photoelectric Sensor (Photomicrosensor) URL: https://www.daidisensor.com/products/slot-sensor/ee-sx67-series-slot-type-photoelectric-sensor/ EE-SX67 series slot-type photoelectric sensor: 8 housing shapes (EE-SX670-EE-SX677), full NPN/PNP output, NO/NC wiring-selectable, 1m/2m/3m pre-wired cable. - The EE-SX67 series slot-type photoelectric sensor integrates a pre-aligned emitter and receiver in a single U-shaped housing, requiring no field beam alignment. - The EE-SX67 series is available in 8 distinct housing shapes (EE-SX670 through EE-SX677), each offered in both NPN and PNP output. - EE-SX67 sensors switch between normally-open and normally-closed operation by wiring: black wire for NO (Light-ON), white wire connected to brown wire for NC (Dark-ON). - Cable length on the EE-SX67 series is specified by suffix: D1 = 1 m, D2 = 2 m, D3 = 3 m. ### FS-KNS Slot Photoelectric Sensor (Plug-in Type) URL: https://www.daidisensor.com/products/slot-sensor/fs-kns-slot-photoelectric-sensor/ FS-KNS slot photoelectric sensor: 5 mm slot, 1 mm min. detectable object, 0.3 ms response, simultaneous NO+NC outputs, 5-24VDC, IP64 ABS housing. - The FS-KNS slot photoelectric sensor has a fixed 5 mm slot width and detects opaque objects down to 1 mm in diameter. - The FS-KNS outputs complementary NO and NC signals simultaneously on separate wires (white = NO, black = NC), without requiring output-mode selection. - The FS-KNS has a maximum response time of 0.3 ms and a maximum switching capacity of 100 mA. - The FS-KNS operates on a wide 5-24 VDC (±10%) supply range, compatible with both 5 V logic and 24 V industrial control circuits. ## laser-distance-sensor Category URL: https://www.daidisensor.com/products/laser-distance-sensor/ ### Specify Working Range, Target and Interface Together Select a laser distance sensor from the actual near and far working positions, the target surface and the controller signal. Range, measurement error, update rate and switching behaviour are separate requirements. Ask for the selected configuration rather than treating every interface listed for a family as simultaneously available. ### Compare the Configuration Paths Required task | Existing product page | What to confirm Long-range industrial distance comparison | [DSK-CG range and output configurations](/products/laser-distance-sensor/dsk-cg-long-range-laser-distance-sensor/) | Choose the model suffix against the published range/output selection table. Phase-shift distance measurement | [DDA-Y / DDB-Y options](/products/laser-distance-sensor/dda-y-and-ddb-y-industrial-laser-distance-sensor/) | Check target conditions, working distance and required measurement output. Alternative long-range package | [DDK-F model data](/products/laser-distance-sensor/ddk-f-long-range-laser-distance-sensor/) | Compare mounting, update requirements and the exact communication or analog option. ### What to Include in a Distance-Sensor Quote Purchase input | Information to provide Target evidence | Send material, colour, angle and a sample or photograph; describe any reflector and outdoor light exposure. Measurement task | State allowable error and update time separately from the maximum distance. Electrical configuration | Specify supply, output range or protocol, cable length and the receiving controller. For short-stroke precision measurement, compare the [laser displacement catalogue](/products/laser-displacement-sensor/); for scanning a whole plane, compare [LiDAR configurations](/products/lidar/). Send the application details and required configuration through the [inquiry form](/contact/) so that the quotation identifies the selected equipment and options. ### DDA-Y & DDB-Y Industrial Laser Distance Sensor (Phase-Shift) URL: https://www.daidisensor.com/products/laser-distance-sensor/dda-y-and-ddb-y-industrial-laser-distance-sensor/ DDA-Y & DDB-Y phase-shift laser distance sensors measure 0.2-100 m at ±(2mm+0.01% of distance), network up to 64 units via RS-485 Modbus RTU, IP67 housing. - The DDA-Y and DDB-Y series measure distance using the phase-shift principle, with a measurement error of ±(2 mm + d × 1/10000) at speed level 1 and 1 mm resolution. - Five range variants are available per series — DDA-Y10/20/30/50/100 and DDB-Y10/20/30/50/100 — all measuring from 0.2 m up to their rated maximum of 10, 20, 30, 50, or 100 m. - Up to 64 DDA-Y/DDB-Y units can be networked on a single RS-485 bus using Modbus RTU protocol, with station addresses 1 to 64. - The DDB-Y series analog output is field-configurable to 0-5 V, 0-10 V, 4-20 mA, 0-20 mA, or 0-24 mA, with a stated accuracy of 0.2%+0.5 mV for voltage and 0.2%+0.005 mA for current. ### DDK-F Long-range Laser Distance Sensor URL: https://www.daidisensor.com/products/laser-distance-sensor/ddk-f-long-range-laser-distance-sensor/ DDK-F long-range laser distance sensor: pulsed TOF ranging up to 200 m, ±3 cm accuracy, IP67, -30 to +60°C, 4-20mA/RS485 Modbus, 4 alarm outputs. - The DDK-F laser distance sensor uses pulsed time-of-flight (TOF) measurement, with a standard version covering 1-150 m at 50 Hz and a high-rate version covering 1-200 m at 100 Hz. - Stated accuracy of the DDK-F is ±3 cm at 100 m in clear weather and ±10 cm in fog and snow conditions. - The DDK-F operates from -30 to +60°C with an IP67 ingress protection rating. - The DDK-F provides 4-20 mA analog, RS-485 Modbus RTU, and four independently configurable NPN/PNP discrete alarm outputs simultaneously. ### DSK-CG Long-range Laser Distance Sensor URL: https://www.daidisensor.com/products/laser-distance-sensor/dsk-cg-long-range-laser-distance-sensor/ DSK-CG long-range laser distance sensor: 56 models, 1 m to 80 m range, 1 mm resolution, 1.5 mm + 0.05% accuracy, analog, RS-485 or switching outputs. - The DSK-CG series offers 56 model variants across 7 measuring ranges from 1 m to 80 m and 4 output types. - Standard-speed DSK-CG models provide 1 mm resolution with accuracy of 1.5 mm + 0.05% of the measured distance. - The DSK-CG measures targets within 30 m using diffuse reflection, without a reflector, regardless of target color, material or surface sheen. - High-speed DSK-CG models (100 Hz) specify 3 cm absolute accuracy, extending to 5 cm on low-reflectance targets and 7 cm on very-low-reflectance targets. ## outdoor-security-sensor Category URL: https://www.daidisensor.com/products/outdoor-security-sensor/ ### Specify the Perimeter Layout and Alarm Interface An outdoor beam detector belongs to a perimeter alarm design, not a machine personnel-protection function. Selection must include line of sight, mounting stability, alarm interface, weather exposure and the response required by the security system. Nominal optical distance is not a guarantee for every outdoor condition. ### Compare the Configuration Paths Required task | Existing product page | What to confirm Outdoor laser beam detection | [DDSK-J perimeter configurations](/products/outdoor-security-sensor/ddsk-j-outdoor-laser-beam-detector/) | Confirm the exact distance class, mounting components, supply and alarm output. ### What to Send for a Perimeter-Sensor Quote Purchase input | Information to provide Site plan | Mark each span, corners, beam height, access routes and possible obstruction or vegetation. Environmental exposure | Describe rain, fog, direct sun, lens contamination and mounting movement. Alarm integration | State the panel input, power availability, cable route and required alarm/fault handling. For industrial navigation or scanned obstacle data, compare [LiDAR configurations](/products/lidar/). Do not substitute a perimeter alarm detector for a safety-rated protective device in a machine stop circuit. Send the application details and required configuration through the [inquiry form](/contact/) so that the quotation identifies the selected equipment and options. ### DDSK-J Outdoor Laser Beam Detector URL: https://www.daidisensor.com/products/outdoor-security-sensor/ddsk-j-outdoor-laser-beam-detector/ DDSK-J outdoor laser beam detector covers up to 500 m per pair, with 100/200/300/500 m ranges, IP67 rating, and 660/980 nm laser wavelength options. - The DDSK-J1001 outdoor laser beam detector offers a selectable detection range of 100, 200, 300 or 500 meters. - DDSK-J1001 provides a choice of 660 nm visible red laser or 980 nm invisible infrared laser, both Class 1 (eye-safe). - Response (beam interruption) time on the DDSK-J1001 is selectable in four steps: 50, 100, 300 or 700 milliseconds. - The DDSK-J1001 has an IP67 ingress protection rating and accepts DC 9-30 V or AC 9-20 V power input. ## laser-switch-sensor Category URL: https://www.daidisensor.com/products/laser-switch-sensor/ ### Select a Laser Switching Layout and Mechanical Package Laser switches provide a switching result; they are not automatically displacement gauges or safety scanners. Choose one-sided diffuse detection or an opposed emitter/receiver arrangement according to target access, then compare spot size, working gap, housing and electrical output for the actual model. ### Compare the Configuration Paths Required task | Existing product page | What to confirm Small one-sided mounting | [DDSK miniature diffuse family](/products/laser-switch-sensor/ddsk-ultra-miniature-laser-diffuse-reflective-sensor/) | Compare body size, usable range on the target and cable exit. Opposed emitter and receiver | [DS miniature through-beam pairs](/products/laser-switch-sensor/ds-miniature-laser-through-beam-sensor/) | Confirm both mounting positions and whether both halves are included. Right-angle mechanical access | [DS right-angle pair options](/products/laser-switch-sensor/ds-right-angle-laser-through-beam-switch-m4-m6/) | Check beam orientation and available bracket space. ### Laser-Switch Configuration Checklist Purchase input | Information to provide Optical access | Describe target colour, transparency, background and available powered mounting sides. Small-feature detection | Provide the minimum feature and actual distance; a small visible spot alone is not a verified detection specification. Electrical and laser instructions | Confirm the selected output and follow the exact product’s laser classification and handling instructions. For distance-selective background rejection compare [photoelectric BGS options](/products/photoelectric-sensor/); for a numerical displacement result compare [laser displacement sensors](/products/laser-displacement-sensor/). Send the application details and required configuration through the [inquiry form](/contact/) so that the quotation identifies the selected equipment and options. ### DDSK Laser Diffuse Reflective Sensor M12 / DK Laser Diffuse Reflective Sensor M18 URL: https://www.daidisensor.com/products/laser-switch-sensor/ddsk-laser-diffuse-reflective-sensor-m12-dk-laser/ DDSK M12 / DK M18 laser diffuse reflective sensors: 650nm visible red laser, 20-500mm detection range, NPN/PNP, NO or NO+NC output, 10-30VDC, IP65. - The DDSK (M12) and DK (M18) laser diffuse reflective sensors use a 650nm visible red laser as the light source. - The DDSK M12 diffuse reflective sensor is available with a 20-200mm or 20-300mm detection distance. - The DK M18 diffuse reflective sensor is available with a 50-300mm or 70-500mm detection distance. - Both series operate on a 10-30VDC supply and carry an IP65 protection rating. ### DDSK Ultra-Miniature Laser Diffuse Reflective Sensor (M3/M4/M5/M6/M8) URL: https://www.daidisensor.com/products/laser-switch-sensor/ddsk-ultra-miniature-laser-diffuse-reflective-sensor/ DDSK ultra-miniature laser diffuse reflective sensor: M3/M4/M5/M6/M8 threaded barrels, 650nm laser, no reflector needed, 10-30VDC, IP65, NPN/PNP NO/NC. - The DDSK M3-M8 series is an ultra-miniature laser diffuse reflective photoelectric sensor using a 650nm red laser diode, available in M3, M4, M5, M6, and M8 threaded barrels. - Each thread size in the DDSK series offers two selectable detection-range variants, from 5-30mm (M3, short range) up to 20-200mm (M6/M8, long range). - The DDSK series operates on a 10-30VDC supply and is rated IP65 for dust and water-jet protection. - Output configuration is selectable between NPN and PNP, with normally-open (NO) or normally-closed (NC) switching logic, giving four output variants per detection-range option. ### DS Laser Through-Beam Sensor M12/M18 (50m) URL: https://www.daidisensor.com/products/laser-switch-sensor/ds-laser-through-beam-sensor-m12-m18/ DS Series M12/M18 laser through-beam sensors reach 50m detection range with a 650nm red laser, NPN/PNP output, NO or NO+NC switching, and IP65 protection. - The DS Series M12 and M18 laser through-beam sensors are both rated for a 50-meter detection distance between transmitter and receiver. - This sensor pair uses a 650nm red laser light source, operates on 10-30VDC, and carries an IP65 ingress protection rating. - Output configurations include NPN or PNP polarity, in either a 3-wire single normally-open (NO) output or a 4-wire output providing both NO and NC signals. - The M12 and M18 housings are threaded metal enclosures sized for standard nut-and-panel mounting. ### DS Miniature Laser Through-Beam Sensor (M3/M4/M5/M6/M8) URL: https://www.daidisensor.com/products/laser-switch-sensor/ds-miniature-laser-through-beam-sensor/ DS Miniature Laser Through-Beam Sensor: M3-M8 threaded housings, ~1.5mm laser spot, up to 20-30m range, NPN/PNP NO/NC output, 10-30VDC, IP65 rated. - The DS miniature laser through-beam sensor is available in M3, M4, M5, M6 and M8 threaded housings, with the M3-M6 versions rated up to 20m detection distance and the M8 version rated up to 30m. - Standard laser spot size on the M3/M4/M5 through-beam sensor is approximately 1.5mm, according to the manufacturer's selection table. - Each thread size is offered in both NPN and PNP transistor output, each available as normally-open (NO) or normally-closed (NC), giving four output variants per size. - The sensor operates on a 10-30VDC supply and is rated IP65 for dust and splash protection. ### DS Right-Angle (90°) Laser Through-Beam Switch M4 / M6 URL: https://www.daidisensor.com/products/laser-switch-sensor/ds-right-angle-laser-through-beam-switch-m4-m6/ DS M4/M6 90° right-angle laser through-beam switch: 650nm laser, 1.5-2mm spot, 20m detection range, 5ms response, IP65 stainless housing, NPN/PNP NO/NC. - The DS M4 and M6 right-angle laser through-beam switches both provide a 20m detection range against a standard 100x100mm white paper target. - The M4 version uses an M4x0.5mm thread with an 18.0mm overall body length; the M6 version uses an M6x0.75mm thread with a 20.0mm overall body length. - Standard laser spot size is approximately 1.5mm for the M4 model and approximately 2mm for the M6 model, both available with custom 0.5mm-1.0mm small-spot options. - Both models operate on 10-30VDC, offer NPN or PNP output with NO or NC selectable logic, and carry an IP65 protection rating in a stainless steel housing. ### F31 Square Laser Photoelectric Switch (Diffuse-Reflective & Through-Beam) URL: https://www.daidisensor.com/products/laser-switch-sensor/f31-square-laser-photoelectric-switch/ F31 square 650nm laser photoelectric switch: diffuse-reflective F31300 (50-300mm) or through-beam F3150M (up to 50m), 10-30VDC, IP65, NPN/PNP NO/NC output. - The F31 series is a 650nm visible red laser photoelectric switch available in diffuse-reflective (F31300, 50-300mm) and through-beam (F3150M, up to 50m) configurations. - F31 sensors operate on a 10-30VDC supply and are rated IP65. - Output is field-selectable between NPN and PNP, with normally-open (suffix 1) or normally-closed (suffix 2) switching action. - The F3150M through-beam variant is supplied as a matched transmitter-receiver pair, with the transmitter identified by a green indicator LED and the receiver by a yellow indicator LED. ### JNS Right-Angle (90°) Laser Diffuse Reflective Sensor — M4 / M6 URL: https://www.daidisensor.com/products/laser-switch-sensor/jns-right-angle-laser-diffuse-reflective-sensor-m4-m6/ JNS 90-degree right-angle laser diffuse sensor: M4 (10-50mm range) or M6 (15-100mm range), 650nm laser, NPN/PNP NO/NC output, 10-30VDC, IP65 rated. - The JNS M4 laser diffuse sensor has a rated detection range of 10-50mm. - The JNS M6 laser diffuse sensor has a rated detection range of 15-100mm. - The JNS 90° laser diffuse sensor uses a 650nm red laser light source. - The JNS series is available with NPN or PNP output, in normally-open (NO) or normally-closed (NC) configuration. ## laser-displacement-sensor Category URL: https://www.daidisensor.com/products/laser-displacement-sensor/ ### Compare Displacement Windows and Measurement Outputs Laser displacement selection begins with the reference position, total movement and real target surface. A repeatability value is not automatically absolute accuracy, resolution or performance on another surface. Keep the selected model, sampling conditions and receiving controller in the same purchase specification. ### Compare the Configuration Paths Required task | Existing product page | What to confirm Published range and interface matrix | [DDK-G model matrix](/products/laser-displacement-sensor/gdk-series-laser-displacement-sensor/) | Choose the exact measuring window and output configuration from the series data. CMOS displacement comparison | [LK-F configurations](/products/laser-displacement-sensor/lk-f-series-cmos-laser-displacement-sensor/) | Compare reference distance, measurement window, target conditions and data output. Additional displacement family | [DK-G model documentation](/products/laser-displacement-sensor/dk-g-series-laser-displacement-sensor/) | Ask for the current ordering sheet where legacy source specifications differ. ### A Displacement Sample Test That Can Be Repeated Purchase input | Information to provide Mechanical reference | Provide sensor standoff, motion direction, minimum and maximum positions and available mounting space. Surface and process | Include dark, reflective or curved samples and expected vibration or ambient light. Measurement acceptance | Define permissible measurement error, repeatability test and update time, then record the selected output. For a target that can be touched, compare [contact displacement probes](/products/contact-displacement-sensor/). For robot process inspection, see the [sensor-role selection article](/news/embodied-ai-robots-factory-sensor-role-selection/) without treating a process sensor as a protective device. Send the application details and required configuration through the [inquiry form](/contact/) so that the quotation identifies the selected equipment and options. ### DK-G Series Laser Displacement Sensor URL: https://www.daidisensor.com/products/laser-displacement-sensor/dk-g-series-laser-displacement-sensor/ DK-G series laser triangulation sensor: 30-400 mm reference distances, repeatability from 10 micron, switching, analog, or RS485 Modbus RTU output. - The DK-G series laser displacement sensor uses laser triangulation with a Class 2, 655 nm red semiconductor laser (max. output 1 mW). - DK-G offers five reference distances from 30 mm to 400 mm, with measuring ranges from ±5 mm to ±200 mm. - Repeatability starts at 10 μm at the 30 mm reference distance. - Response time is switchable at 1.5 ms, 5 ms, or 10 ms. ### DDK-G Laser Displacement Sensor 30-250 mm URL: https://www.daidisensor.com/products/laser-displacement-sensor/gdk-series-laser-displacement-sensor/ DDK-G laser displacement sensor (formerly GDK): 20 models across 30/50/85/120/250 mm reference distances, 2-75 um resolution, +/-0.1% F.S. linearity, IP64, 655 nm Class 2 laser. Full 2026 datasheet specs and English PDF download. - DDK-G is the current factory model code; GDK was the former catalogue listing of the same series - order codes on new paperwork read DDK-G30NM through DDK-G250P-485. - Twenty standard models: five reference distances (30/50/85/120/250 mm) x two polarities (N = NPN, P = PNP) x two interfaces (M = analog current or voltage, -485 = RS485). - Resolution follows the grade: 2 / 5 / 10 / 30 / 75 um in high-resolution mode, coarsening to 4-150 um in fast mode - the nearer the reference distance, the finer the reading. - Full-scale linearity holds +/-0.1% through the four nearer grades and relaxes to +/-0.3% on the 250 mm grade - for the G30 that bounds deviation within roughly 8 um over its 8 mm span. ### LK-F Series CMOS Laser Displacement Sensor URL: https://www.daidisensor.com/products/laser-displacement-sensor/lk-f-series-cmos-laser-displacement-sensor/ LK-F series CMOS laser displacement sensor: 16 models, 30-400mm reference distance, up to 10μm repeatability, switching + 0-5V/4-20mA analog output, IP67. - The LK-F series offers 16 model variants across five reference distances (30, 50, 100, 200 and 400 mm), each available in NPN and PNP output logic. - M-type LK-F sensors provide both a discrete switching output and an analog output (0-5 V or 4-20 mA, field-selectable in PRO mode) from a single unit. - At its 30 mm reference distance, the LK-F sensor achieves a measuring range of ±5 mm with 10 μm repeatability. - At its 400 mm reference distance, the LK-F sensor covers a measuring range of ±200 mm, with repeatability of 400 μm over 200-400 mm and 800 μm over 400-600 mm. ## hot-metal-detector Category URL: https://www.daidisensor.com/products/hot-metal-detector/ ### Specify the Metal-Detection Task and Installation Environment For a metal-processing line, state what must be detected and how the target passes the sensor. Target temperature, scale, glare, steam, dust, vibration and mounting distance are application inputs; a family name alone does not establish operation in every furnace or rolling-line condition. ### Compare the Configuration Paths Required task | Existing product page | What to confirm Hot/cold metal detection package | [DK-SCZ-II configuration](/products/hot-metal-detector/dk-scz-ii-hot-and-cold-metal-detector/) | Check the published sensing principle, distance, interface and required protective installation. ### Metal-Line Application Data for a Quote Purchase input | Information to provide Target state | Provide material, expected temperatures, surface condition and minimum object dimensions. Sensor location | Show mounting distance, angle, exposure, protective window and any air purge or cooling requirement. Line interface | Specify the required detection result, timing, receiving controller and supply. If the task needs a distance value rather than a presence signal, compare the [laser distance catalogue](/products/laser-distance-sensor/). Ask for written validation of any environmental requirement absent from the model data. Send the application details and required configuration through the [inquiry form](/contact/) so that the quotation identifies the selected equipment and options. ### DK-SCZ-II Hot & Cold Metal Detector (Laser Distance Type) URL: https://www.daidisensor.com/products/hot-metal-detector/dk-scz-ii-hot-and-cold-metal-detector/ DK-SCZ-II active laser hot & cold metal detector: 1mm accuracy, 0.1-3/5/10/20m ranges, switching + 4-20mA + RS232 outputs, IP65 water/air-cooled housing. - The DK-SCZ-II is an active laser-based sensor, so it detects both cold and hot metal targets, unlike passive infrared hot metal detectors, which only respond to a target's own thermal radiation. - The DK-SCZ-II delivers 1 mm accuracy, 0.1 mm resolution, and 0.5 mm repeatability at a 10 Hz measuring rate. - The DK-SCZ-II is available in four selectable measuring ranges: 0.1-3 m, 5 m, 10 m, and 20 m. - The DK-SCZ-II provides three output interfaces on one unit: a programmable discrete switching output, a scalable 4-20 mA analog output, and an RS232 serial data interface (RS422 on request). ## press-brake-protection Category URL: https://www.daidisensor.com/products/press-brake-protection/ ### Press Brake vs Punch Press: Two Different Guarding Problems Presses and press brakes need a safeguarding solution matched to the machine and the operator task. A fixed field across an access opening and a ram-mounted laser system monitor different geometries; neither is automatically suitable for every machine of that name. A press-brake risk assessment must account for sheet handling, tooling, side and rear access, stopping performance, operating modes and the applicable machine standard. A fixed light curtain is not universally prohibited, and a ram-tracking device is not a complete safeguarding solution by itself. Compare the [DKE-L3 ram-mounted laser configuration](/products/press-brake-protection/dke-l3-press-brake-laser-protection/), [DQS controller-based photoelectric guard](/products/press-brake-protection/dqs-press-photoelectric-safety-guard/) and [DQV double-sided system](/products/press-brake-protection/dqv-double-sided-photoelectric-safety-protection-device/). Request the complete equipment configuration and evidence for the intended machine. Figure context: Conceptual application, not an installation prescription. The integrator must select and validate the safeguards. ### Which of the Three Systems Fits Your Machine? Compare the published configurations below as procurement starting points. Sensor response, optical spacing, output arrangement and machine-level stopping time are separate quantities; a table does not establish a certified combination. Attribute | DKE-L3 (press brake) | DQS (press / hydraulic) | DQV (dual zone) Guarding principle | 3-beam laser band that travels with the ram | fixed curtain + dedicated controller | two independent curtains, one controller Response time | 5 ms | ≤ 10 ms | ≤ 10 ms Detection capability / optical pitch | 10 mm published detection capability; verify exact document | 7 pitches: 10 / 14 / 20 / 25 / 30 / 40 / 80 mm | 10 / 20 / 40 / 80 mm per side Coverage | spans up to 15 m between brackets | protective height 50–2480 mm (4–32 beams) | up to 72 beams / 5680 mm combined Published output (verify selected version) | dual OSSD + FA fast-approach enable | relay contacts AC250V / 5A from the controller | dual relay or dual transistor Supply | 12–24 VDC | sensors DC 12/24 V; controller AC 110–220 V | controller AC 110–220 V Ingress protection | IP65 | IP65 | IP65 Figure context: Three guarding architectures — pick by machine geometry, not by price. Not sure which of the three? Send the machine type, bed length and measured stopping time via the [inquiry form](/contact/) — we reply with a model code, not a brochure. ### Press Brake Laser Protection: How Ram-Tracking Guarding Works DKE-L3 uses ram-mounted transmitter and receiver brackets with the E1, E2 and E3 optical arrangement described in its instructions. Verify the applicable setup distance, tooling geometry, bracket alignment and operating mode from the exact version. A conceptual diagram is not a universal 3 mm installation prescription or proof that every hazard point is covered throughout the stroke. The published optical geometry and FA fast-approach signal must be checked against the exact DKE-L3 instructions and the machine interface. The device response is not the machine stopping time; do not derive a safe working position from the nominal sensor response alone. Verify the laser classification and all operating precautions in the applicable manual. Alignment across long beds is the practical worry, and it is why the system spans up to 15 m with bracket geometry designed for repeatable re-mounting after tool changes. Figure context: Verify offsets, tooling, alignment and operating modes from the applicable instructions. This is not an installation approval. ### Guarding Power Presses and Hydraulic Presses with the DQS System DQS combines a light-curtain configuration with a controller. Request the selected controller code, contact arrangement, input documentation and applicable safety evidence as one package. Do not assume Type 4, EDM or whole-machine compliance from the product family name; those requirements need explicit documentation for the selected configuration. The controller family covers both retrofit and OEM builds. DQSW and DQSS are stand-alone boxes for adding protection to presses already on the floor; DQSN and DQSP are panel-mount versions for building into new machine cabinets. Output configuration is ordered by code — OC (1 NO + 1 NC), 2C (two NC) or 2O (two NO) — and detection distance is coded from class A (0.3–3 m) up to class H (0.3–40 m), so one series covers a bench press and a forty-meter transfer line alike. Choose beam pitch, beam count and field height from the DQS model table. Ask separately for the minimum detectable object and applicable rating; pitch is not a synonym for detection capability. Figure context: Model code example: DQS06/10-50 = 6 beams × 10 mm pitch, 50 mm protective height. ### The Mounting Distance Comes From Your Machine's Stopping Time No guarding system on this page has a fixed "correct" mounting distance, because the minimum distance is a property of *your machine*, not of the sensor: it grows with the total time the press takes to actually stop after the output drops. A press with a tired brake needs the curtain further out than an identical press with a fresh one. That is why every serious **press brake safety** installation starts with a measured stopping time, and why we ask for that number in the inquiry rather than publishing a one-size answer. Collect the measured machine stopping time together with sensor, controller and output-element response information. The integrator must use the applicable standard edition and approach geometry to determine the safeguard position. The [press and press-brake procurement article](/news/press-brake-punch-press-light-curtain-guarding/) helps assemble those inputs; examples are not a substitute for machine validation. For pin-level output wiring — OSSD polarity, relay loop details, reset circuits — the DAIDISIKE engineering library on [fsddsk.com](https://www.fsddsk.com/safety-light-barrier-wiring-diagram) maintains the full diagram set for every output type we ship. ### What We Publish — and What to Ask the Factory For Every number above comes from the published series data, and the model tables on the three product pages list the ordering codes in full. Two things we deliberately do not print here: performance-level certificates (PL / functional-safety documentation is supplied per order, with the paperwork matched to the exact configuration shipped) and stopping-time-dependent mounting distances, which are meaningless without your measurement. If a spec you need is missing from a product page, that is a data gap we flag honestly rather than a number we invent — ask, and the factory answers with documents. ### Category FAQ Q: Can I use a standard safety light curtain on a press brake? A: Possibly, depending on machine design, operating task, stopping performance and the applicable machine standard. A fixed light curtain and a ram-mounted laser system have different application constraints. Have the integrator validate the intended arrangement rather than assuming either option fits every press brake. Q: What is the difference between a press brake laser guard and a press light curtain? A: A ram-mounted laser guard and a fixed light-curtain/controller arrangement monitor different geometries. Compare their exact setup instructions, documented detection capability, device response and output interfaces. A nominal optical offset is not a universal installation distance, and beam pitch must not be substituted for detection capability. Q: Do these systems include the safety relay? A: DQS and DQV are controller-based configurations; confirm exactly which controller, contacts and accessories the quotation includes. DKE-L3 requires a documented evaluation and machine interface. Review the [safety relay options](/products/safety-relay/) only after checking exact input compatibility and required safety functions; a brand match is not approval of the combination. Q: How do I choose between DQSW, DQSS, DQSN and DQSP controllers? A: W and S versions are stand-alone boxes for retrofitting presses already in service; N and P versions are panel-mount for OEM cabinets. Output codes: OC = 1 NO + 1 NC, 2C = two NC, 2O = two NO contacts. Q: What should I send to get an accurate quote? A: Machine type (press brake, punch press, shear or hydraulic press), bed length or opening width × height, the resolution class you need, and the measured stopping time. The stopping time decides the mounting distance and often the model — it is the one number no catalogue can supply for you. ### DKE-L3 Press Brake Laser Protection URL: https://www.daidisensor.com/products/press-brake-protection/dke-l3-press-brake-laser-protection/ DKE-L3 press brake laser guarding system: 3 beams (E1/E2/E3), 5ms response, 10mm resolution, 15m range, dual OSSD outputs, FA fast approach, IP65, 12-24VDC. - DKE-L3 uses three laser beams (E1/E2/E3) mounted beside the ram, with beam E1 set 3 mm below the punch tip, to guard the point of operation as the ram descends. - The system's dedicated FA (fast approach enable) output on receiver pin 7 permits high-speed ram closing while the protective field is clear. - DKE-L3 provides dual OSSD safety outputs (OSSD1 on pin 9, OSSD2 on pin 8) for interfacing with a press brake's CNC or hydraulic safety circuit. - Response time is 5 ms with 10 mm resolution. ### DQS Press Photoelectric Safety Guard URL: https://www.daidisensor.com/products/press-brake-protection/dqs-press-photoelectric-safety-guard/ DQS Type 4 press photoelectric safety guard: dual relay controller output, ≤10ms response, 4-32 beams, 10-80mm pitch, 50-2480mm protective height, IP65. - DQS is a Type 4 photoelectric safety light curtain system for point-of-operation guarding on power presses, combining a light curtain with a dedicated safety controller that outputs dual relay dry contacts. - DQS has a response time of ≤10 ms. - DQS is available in seven beam-pitch options — 10, 14, 20, 25, 30, 40, and 80 mm — with 4 to 32 beams, giving protective heights from 50 mm to 2480 mm. - DQS controllers are available in external stand-alone form (DQSW, DQSS) for retrofit installations and built-in panel-mount form (DQSN, DQSP) for OEM integration. ### DQV Double-sided Photoelectric Safety Protection Device URL: https://www.daidisensor.com/products/press-brake-protection/dqv-double-sided-photoelectric-safety-protection-device/ DQV double-sided photoelectric safety device runs two independent light-curtain sets, up to 72 beams, 5680mm height, IP65, dual relay output, ≤10ms response. - The DQV double-sided photoelectric safety protection device runs two independent light-curtain sets from a single controller, each with its own output circuit. - DQV supports beam pitch options of 10, 20, 40, and 80 mm, selectable independently per protected side. - At 80 mm pitch, a single DQV light-curtain side can reach up to 72 beams and a 5680 mm protective height. - The DQV controller outputs dual relay dry contacts or dual transistor signals per side, with a response time of ≤10 ms. ## lidar Category URL: https://www.daidisensor.com/products/lidar/ ### Choose a Scanner by the Result Your Controller Needs Separate a safety protective field from ordinary obstacle detection and navigation data before comparing distance. The catalogue includes safety scanning, configurable discrete-output devices and measurement/navigation scanners. A long maximum range or a software stop zone does not turn a measuring scanner into a safety device. ### Compare the Configuration Paths Required task | Existing product page | What to confirm Personnel protective-field evaluation | [ST27 protective-scanning configurations](/products/lidar/st27-safety-laser-scanner/) | Request exact model, protective-field limits, OSSD interface and applicable safety evidence. Navigation and mapping data | [DLD-50D navigation/measuring scanner](/products/lidar/dld-50d-2d-tof-lidar-for-navigation-and-mapping/) | Confirm data interface, scan settings, host software and target conditions; not personnel safeguarding. Obstacle output and measurement requirements | [DLD50T8N / DLD50T8P options](/products/lidar/dld50t8n-dld50t8p-50-m-measuring-lidar-with-discrete-i-o-ethernet/) | Specify output polarity, required data and target reflectivity before ordering. ### A LiDAR Sample-Evaluation Request Purchase input | Information to provide Target and working distance | Give the darkest expected target, minimum size, usable range and approach direction; do not quote only maximum catalogue distance. Mounting and coverage | Include scan-plane height, blind areas, moving platform geometry and environmental exposure. Controller handoff | List the required discrete signals or data interface and ask for the matching configuration tool and instructions. Use the [2D LiDAR selection guide](/guides/how-to-choose-a-lidar-scanner/) to prepare the comparison, and the [robot-cell sensor-role checklist](/news/embodied-ai-robots-factory-sensor-role-selection/) when sensing and safeguarding share one cell. Send the application details and required configuration through the [inquiry form](/contact/) so that the quotation identifies the selected equipment and options. ### DLD-100D Single-Line TOF Scanning LiDAR URL: https://www.daidisensor.com/products/lidar/dld-100d-single-line-tof-scanning-lidar/ DLD-100D single-line TOF scanning LiDAR: up to 100 m range, 905 nm Class 1 laser, 280°/360° scan angle, IP67 housing, Ethernet output for AGV and robot use. - The DLD-100D single-line TOF LiDAR detects targets up to 100 m away at 90% reflectivity and 40 m away at 10% reflectivity, with a ranging accuracy of ±20 mm (±10 mm within 0.1-15 m). - DLD-100D uses a 905 nm Class 1 laser source, drawing a maximum of 3 W from a 9-36 V DC supply. - The DLD-100DC variant scans a full 360°, while DLD-100DH and DLD-100DP scan 280°; DLD-100DH and DLD-100DC support selectable 0.08°/0.16°/0.32° angular resolution at 50/25 Hz, while DLD-100DP runs at a fixed 100 Hz with 0.32° resolution. - DLD-100D is rated IP67, measures 60 x 60 x 80 mm, weighs 250 g excluding cable, and outputs data over a standard Ethernet 100BASE-TX interface. ### DLD-50D 2D TOF LiDAR for Navigation & Mapping (50 m) URL: https://www.daidisensor.com/products/lidar/dld-50d-2d-tof-lidar-for-navigation-and-mapping/ DLD-50D 2D TOF LiDAR: 50 m range (90% remission), ±20 mm repeatability, 280° FoV, IP67, 250 g, 2.5 W, Ethernet output for AGV/AMR navigation & mapping. - The DLD-50D 2D TOF LiDAR delivers ±20 mm repeatability across a 280° field of view, with an 80° blind sector at 320°–0°–40°. - The DLD-50D is rated for a 50 m detection range at 90% target remission, and a guaranteed 20 m at 10% remission. - The DLD-50DH model offers selectable 0.08°/0.16°/0.32° angular resolution at 50 Hz; the DLD-50DP model runs 0.32° resolution at 100 Hz. - The DLD-50D operates on a 225 kHz ranging sample rate and withstands ambient light above 100,000 lux. ### DLD-50G 2D Single-line LiDAR (Diffuse-remission Measuring Type) URL: https://www.daidisensor.com/products/lidar/dld-50g-2d-single-line-lidar/ DLD-50G is a 2D single-line laser scanning lidar built for diffuse-remission measurement on natural surfaces, no reflector or cooperative target required. - The DLD-50G is classified in DAIDISIKE's catalog as a 2D single-line laser scanning lidar of the diffuse-remission measuring type. - As a diffuse-remission measuring device, the DLD-50G is designed to read distance from the natural surface reflectivity of the target, without requiring an installed reflector or cooperative target. - The DLD-50G performs a single-line 2D scan, producing a distance profile across a cross-section on each rotation rather than a single fixed-point reading. ### DLD05A3 2D TOF Obstacle-avoidance LiDAR (5 m) URL: https://www.daidisensor.com/products/lidar/dld05a3-2d-tof-obstacle-avoidance-lidar/ DLD05A3 2D TOF Obstacle-avoidance LiDAR: 0.05-5 m range, 270° field, 3 NPN/PNP switching outputs, 16 zone sets, IP65, 50×50×76 mm, no protocol stack. - Outputs 3 discrete switching signals (NPN or PNP) plus 1 status signal, with no fieldbus or point-cloud output. - Detection range is 0.05–5 m across a 270° scanning angle, with ±30 mm detection accuracy. - Angular resolution is selectable at 0.1° or 0.3°, with scan frequencies of 15 Hz or 30 Hz. - Stores 16 zone sets, each defining 3 detection zones mapped to the sensor's 3 switching outputs. ### DLD20A5-5N / DLD20A5-5P 2D TOF Obstacle-avoidance LiDAR (20 m) URL: https://www.daidisensor.com/products/lidar/dld20a5-5n-dld20a5-5p-2d-tof-obstacle-avoidance-lidar/ DLD20A5-5N/-5P 2D TOF LiDAR: 0.05-20 m range, 270° scan, 3x NPN/PNP discrete outputs, 16 zone sets, ±30 mm accuracy, IP65, DC9-28V. No bus, no SDK, no code. - The DLD20A5 2D TOF LiDAR detects objects from 0.05 m to 20 m and outputs three NPN or PNP discrete switch signals plus one status signal, with no Ethernet or bus protocol involved. - The DLD20A5 scans a 270° field at a selectable 15 Hz or 30 Hz rate, with 0.1° or 0.3° selectable angular resolution and ±30 mm detection accuracy. - The DLD20A5 uses a 905 nm, Class 1 laser source and carries an IP65 ingress protection rating, operating on a DC9-28V supply. - The DLD20A5 stores 16 zone sets, each providing three nested detection fields mapped to its three discrete outputs, enabling staged warning/slow-down/stop responses. ### DLD30T-5N Single-line TOF Measuring 2D LiDAR (30 m) URL: https://www.daidisensor.com/products/lidar/dld30t-5n-single-line-tof-measuring-2d-lidar/ DLD30T-5N single-line TOF 2D LiDAR: 30 m/90% reflectivity range, 0.08° angular resolution, 270° scan, 100BASE-TX Ethernet point-cloud output, IP67, 148 g. - The DLD30T-5N single-line TOF LiDAR detects up to 30 m on 90% reflectivity targets and 10 m on 10% reflectivity targets. - The DLD30T-5N has an adjustable angular resolution down to 0.08°, across a 270° scan angle. - The DLD30T-5N outputs point-cloud measurement data over a 100BASE-TX Ethernet interface. - The DLD30T-5N scan frequency is adjustable from 10 Hz to 30 Hz. ### DLD50T8N / DLD50T8P — 50 m Measuring LiDAR with Discrete I/O + Ethernet URL: https://www.daidisensor.com/products/lidar/dld50t8n-dld50t8p-50-m-measuring-lidar-with-discrete-i-o-ethernet/ DLD50T8N/DLD50T8P 50 m TOF measuring lidar: 280 degree scan, +/-30 mm accuracy, NPN/PNP discrete I/O plus 100BASE-TX Ethernet output, IP67, 9-36 V DC supply. - The DLD50T8N/P is a 2D single-line TOF lidar rated for 50 m detection at 90% target remission and 20 m at 10% remission, with ±30 mm accuracy. - DLD50T8N provides NPN discrete output at 50 Hz scan frequency with selectable 0.08°/0.16°/0.32° angular resolution; DLD50T8P provides PNP discrete output at 100 Hz scan frequency with 0.32° angular resolution. - Both variants scan a 280° field of view and output data over 100BASE-TX Ethernet in addition to their discrete NPN/PNP output. - The sensor operates on 9-36 V DC, is IP67 rated, uses a Class 1 laser, and measures 60×60×80 mm at 250 g. ### DLDS2030A-5S Laser Scanning Radar URL: https://www.daidisensor.com/products/lidar/dlds2030a-5s-laser-scanning-radar/ DLDS2030A-5S laser scanning radar from DAIDISIKE: a 2D LiDAR-type sensor with its own catalogue page and a dedicated 6-piece accessory line, DLDS-1 to DLDS-6. - DLDS2030A-5S is a laser scanning radar model in DAIDISIKE's laser radar product line, given a dedicated page in the factory catalogue alongside the DLD-05D and DLD-20D series. - A dedicated factory accessory line, DLDS-1 to DLDS-6, is available for the DLDS2030A-5S scanner. - As of the current documentation review, the DLDS2030A-5S does not appear on either of DAIDISIKE's two prior company websites. ### SDLD-05A TOF Laser Radar (Obstacle-Avoidance Type) URL: https://www.daidisensor.com/products/lidar/sdld-05a-tof-laser-radar/ SDLD-05A TOF laser radar: 270° scan, 0.1-14m range, ±30mm accuracy, 16 switchable zone groups, Ethernet UDP + NPN I/O for AGV/RGV obstacle avoidance. - The SDLD-05A TOF laser radar scans a 270° field of view with a detection range of 0.1-14m at 90% target reflectivity (0.1-8m at 10% reflectivity) and ±30mm measurement accuracy. - Detection zones are organized as 16 switchable zone groups, each with 3 independently editable sub-zones in polygon (up to 15 vertices), fan, or rectangular shapes. - Zone group selection is controlled by a 4-bit digital input code (IN1-IN4), addressing 16 pre-configured zone groups (0-15) without reprogramming the sensor. - The unit combines an Ethernet (RJ45, UDP) interface with NPN digital I/O (up to 4 inputs, 4 outputs) and a USB Type-C configuration port. ### ST27 Series Safety Laser Scanner (Type 3 ESPE, 3 m / 5 m Protective · 20 m Warning · 60 m Measuring) URL: https://www.daidisensor.com/products/lidar/st27-safety-laser-scanner/ ST27 safety laser scanner: Type 3 ESPE (IEC 61496), SIL 2, Cat. 3 / PL d, 276° scan, 3 m or 5 m protective field, 100 ms response, IP65, PNP OSSD. Six models. - The ST27 series is rated Type 3 to IEC 61496-1, SIL 2 to IEC 61508, and Category 3 / Performance Level d to ISO 13849, as an AOPDDR-type electro-sensitive protective equipment under IEC 61496-3. - ST27 scans 276° at 30 Hz with 0.1° angular resolution, using a 905 nm Class 1 laser source to IEC 60825-1:2014. - The protective field is 3 m on ST27-03S / 03D / 03P and 5 m on ST27-05S / 05D / 05P, specified at 1.8% remission — the worst case, representing deep black clothing. - The ST27 warning field reaches 10 m (03x models) or 20 m (05x models) at 10% remission, and the measuring range reaches 40 m (03x) or 60 m (05x) at 70% remission. Neither is a safety function. ## measuring-light-curtain Category URL: https://www.daidisensor.com/products/measuring-light-curtain/ ### Measuring, Not Guarding — What These Light Curtains Are For A **measuring light curtain** looks exactly like its safety cousin — two aluminium profiles, a fence of infrared beams between them — but it answers a completely different question. A safety curtain asks *"is something in the opening?"* and stops a machine. A measuring curtain asks *"how tall, how wide, where, and how many?"* and reports the answer to your PLC as data. The DQL, DQM and DQLV series on this page carry no IEC 61496 Type rating and no ISO 13849 category, deliberately: they are measurement and detection instruments, and we say so plainly rather than dressing them in safety language. That makes this the right page if you searched for a **non safety light curtain**, a **light grid sensor**, or an infrared curtain for dimensioning, profiling, counting, hole detection or vehicle separation. If your application must protect people — stopping a press when a hand enters — leave this page now and specify from the [safety light curtain category](/products/safety-light-curtain/) instead; no measuring product belongs in a personnel-protection circuit. Figure context: Two frame formats: the full beam bitmap, or just the edges and count — object height and position in a single frame. ### DQL vs DQM vs DQLV: Choose by Output, Not by Looks Choose the measurement or detection result and controller interface before the housing. [DQL](/products/measuring-light-curtain/dql-measuring-light-curtain/) provides analog or serial-data configurations; [DQM](/products/measuring-light-curtain/dqm-measuring-light-curtain/) provides NPN or PNP switching outputs for detection and counting, with a confirmed 0.5 ms response and no RS485 or RS232. [DQLV](/products/measuring-light-curtain/dqlv-vehicle-separation-light-curtain/) is the vehicle-separation family. These are not interchangeable safety devices. Attribute | DQL | DQM | DQLV (vehicle) Output | 4–20 mA current, voltage output, or RS-485/232 | NPN or PNP switching, direct | vehicle-separation logic outputs Protocol | Modbus RTU (customised frames) | — | — Finest beam pitch | 1.25 mm | 2.5 mm | Verify optical pitch and reported measurement specification separately Max beams / height | 496 beams / 3990 mm | per model table | up to 1420 mm Response | per configuration | 0.5 ms (confirmed for all DQM specifications) | ≤ 15 ms Special ability | push frames every 100 ms or polled multi-drop | no controller needed at all | Vehicle-separation logic; validate actual vehicles and lane conditions Environment | IP65 (IP68 as DQLF) | IP65 (IP68 as DQMF) | IP67 + optional heater hood Figure context: Same optics, three output philosophies — the deciding question is what your control system accepts. Tell us what you are measuring — object size, line speed, and what your PLC accepts (4–20 mA, RS-485 or a dry contact) — via the [inquiry form](/contact/), and the reply is a full model code like DQL08/10-70. ### Select Beam Pitch, Field Height and Measurement Requirements Beam pitch determines optical sampling positions; it is not automatically the smallest detectable object, measurement accuracy or repeatability. Target shape, optical beam size, scanning logic and installation affect the result. DQL lists pitch options down to 1.25 mm and DQM down to 2.5 mm; use the model-specific range and test the real target rather than treating either number as a universal detection guarantee. Order from the published beam-count and height table, then ask for a sample test at the intended speed, target orientation and working span. For dimensioning, define the required measurement error and update time separately. For counting, define the minimum target and gap so that a switching result is not mistaken for a full profile measurement. Figure context: Pitch, minimum detectable object, measurement error and update time are different fields in the purchase specification. ### Analog 4–20 mA and Modbus RTU Integration On the serial side, the DQL speaks Modbus RTU with two frame styles. Mode 1 transmits the complete beam bitmap — every beam's clear/blocked state, every cycle — which is the format for profiling and hole-detection work where the *shape* matters. Mode 2 compresses each scan to three numbers: highest blocked beam, lowest blocked beam, and total blocked count — one compact frame that yields object height, vertical position and a presence count, which covers most dimensioning and sorting jobs at a fraction of the bus load. Delivery is either active push (the curtain transmits on its own clock, 100 ms by default) or passive polling, which lets several curtains share one RS-485 trunk and answer by address. Baud rates run 4800 to 38400. On the analogue side, 4–20 mA current output is the standard configuration; for voltage output the catalogue currently prints more than one range on different pages (1–10 V, 0–10 V and 1–5 V appear), so treat the voltage option as configure-at-order and have the factory confirm the range in writing — we would rather flag our own catalogue's inconsistency than let it surprise you at commissioning. The [relay and I/O module catalogue](/products/relay-module/) provides additional automation options, but a shared RS485 interface does not prove direct compatibility. Confirm the master/host and slave roles, addressing, register or custom-frame format, polling method and electrical interface. Two slave devices cannot be assumed to exchange data without a suitable host. Bus wiring, termination and sensor-output reference material beyond this page lives in the DAIDISIKE engineering library on [fsddsk.com](https://www.fsddsk.com/installation-wiring) — this page stays at the integration level. ### Vehicle Separation: Validate the Target and Lane Configuration DQLV targets vehicle separation rather than fine-object measurement. Its published data describes a 150 mm minimum-object condition and a separate resolution figure; those are different specifications. Validate the complete vehicle sequence, lane geometry, mounting and environmental conditions instead of assuming birds, spray or trailer gaps can never affect a transaction. The series page lists housing, operating-temperature and optional hood configurations. Quote the lane width, environmental exposure, power budget and required output with the [DQLV model data](/products/measuring-light-curtain/dqlv-vehicle-separation-light-curtain/). Optional heating does not by itself guarantee operation in every icing condition. Figure context: Application examples: object/profile data and vehicle separation need different target and environmental validation. ### When a Measuring Curtain Is the Wrong Device If the installation protects people, do not use DQL, DQM or DQLV as the personnel-protection device: evaluate the [safety light-curtain configurations](/products/safety-light-curtain/) and their exact documentation instead. If fine displacement rather than beam interruption is required, compare [laser displacement sensors](/products/laser-displacement-sensor/) against the target and accuracy requirement. For washdown, specify water pressure, chemicals and temperature; an IP label alone does not establish suitability for the cleaning process. ### Category FAQ Q: Is a measuring light curtain a safety device? A: No. The DQL, DQM and DQLV publish no IEC 61496 Type rating and no ISO 13849 category, and must never be the device that stops a machine to protect a person. For personnel protection, specify from the [safety light curtain category](/products/safety-light-curtain/) — same optical idea, completely different engineering duty. Q: What is the difference between DQL and DQM? A: DQL offers analog and serial-data configurations for measurement. DQM supplies NPN or PNP switching outputs for detection and counting, has a confirmed 0.5 ms response and does not provide RS485/RS232. Compare the actual model table, span and required result rather than treating the difference as a connector choice. Q: What data can I read over RS-485? A: Two frame formats: the full beam-state bitmap (Mode 1), or highest blocked beam + lowest blocked beam + blocked count (Mode 2). Frames arrive by active push — every 100 ms by default — or by passive polling, which allows several curtains on one bus, addressed individually. Baud 4800–38400. Q: What is the finest resolution available? A: DQL lists beam-pitch options down to 1.25 mm and DQM down to 2.5 mm. These are optical spacing figures, not universal measurement-accuracy or minimum-object guarantees. Confirm span, model code and performance on the intended target. Q: Can the DQLV replace a buried loop for vehicle detection? A: DQLV is a vehicle-separation option that does not require a buried loop, but suitability depends on lane layout, vehicles, required output and environmental testing. Do not assume its small-object filtering or optional hood prevents every false transaction. ### DQL Measuring Light Curtain (Analog/RS485) URL: https://www.daidisensor.com/products/measuring-light-curtain/dql-measuring-light-curtain/ DQL Measuring Light Curtain: analog voltage/4-20mA plus RS-485/RS-232 Modbus RTU output, 1.25-80mm beam spacing, up to 496 beams, heights to 3990mm. - DQL's analog output is 4-20 mA current, or a voltage output that the catalog labels inconsistently — 1-10 V in the model-code key, 0-10 V in the general spec-table header, and 1-5 V in the wiring diagram — so the exact voltage range should be confirmed with the factory before ordering. - DQL also offers RS-485/RS-232 serial communication on a customized Modbus RTU protocol: 4800/9600(default)/19200/38400 bps, 8 data bits, no parity, 1 stop bit, 16-bit CRC. - Two serial frame modes are selectable: Mode 1 uploads the full beam-status bitmap to the host; Mode 2 uploads only the highest blocked point, lowest blocked point, and total blocked-beam count. - Transmission is selectable as active (auto-push, default every 100 ms, interval adjustable) or passive (host polls; multiple curtains can share the bus, each with its own address code). ### DQLV Vehicle Separation Light Curtain URL: https://www.daidisensor.com/products/measuring-light-curtain/dqlv-vehicle-separation-light-curtain/ DQLV vehicle-separation light curtain: 150 mm minimum detectable object, 20/40/80 mm spacing, 4-72 beams, IP67, controller-free NPN/PNP/relay/RS-485 output. - The DQLV vehicle-separation light curtain detects objects 150 mm and larger only, by design, so birds, insects, and glare do not trigger a false vehicle-present signal, per the DAIDISIKE catalog. - DQLV beam spacing comes in 20, 40, or 80 mm, with beam counts from 4 to 72 (20 mm pitch, up to DQLV72/20-1420, a 1420 mm protected height), 4 to 36 (40 mm pitch, up to DQLV36/40-1400), or 4 to 18 (80 mm pitch, up to DQLV18/80-1360). - DQLV response time is 15 ms or less, and the catalog states it suppresses 99% of interference from electromagnetic sources, strobe lighting, welding arcs, and surrounding light sources. - In its dual-channel transistor output configuration, DQLV outputs two separate NPN or PNP signals: channel 1 reports vehicle detection, channel 2 reports a light-curtain fault alarm; wiring runs over a seven-core cable directly into the lane controller, with no external controller required. ### DQM Measuring Light Curtain (Switching Output) URL: https://www.daidisensor.com/products/measuring-light-curtain/dqm-measuring-light-curtain/ DQM object detection and counting light curtain: NPN or PNP switching output, 0.5 ms response across all specifications, 2.5-80 mm beam spacing. No RS485/RS232. - The DQM measuring light curtain changes its NPN or PNP output state when any beam across the detection height is interrupted; the ordered NO/NC logic determines which state represents detection. - Switching output is selectable by order code: A = NPN normally-closed, B = PNP normally-closed, C = NPN normally-open, D = PNP normally-open. - The finest beam spacing offered in the DQM series is 2.5 mm, starting from model DQM32/2.5-77.5; DQM does not offer the 1.25 mm spacing available on the analog/RS-485 DQL series. - DQM is available in six beam-spacing options: 2.5, 5, 10, 20, 40, and 80 mm, with protection heights from 60 mm up to 3,990 mm across the published model list. ## safety-door-lock Category URL: https://www.daidisensor.com/products/safety-door-lock/ ### Choose a Safety Interlock Switch by Guard Function A **safety interlock switch** either monitors whether a machine guard is closed, or monitors and physically locks it. Monitoring without locking requires the hazard to stop before a person can reach it, as verified by the machine risk assessment. Use guard locking when the assessment requires the door to remain closed until a persistent hazard has ended and release is permitted. This category includes mechanical tongue switches, magnetic coded and RFID non-contact switches, solenoid guard locks, actuator keys and a mechanical safety-door bolt. The first decision is monitoring versus locking; the second is contact, magnetic or RFID actuation. Figure context: Monitoring confirms door position; guard locking also prevents opening while the hazard remains. ### Safety Door Switch and Guard Locking Range For mechanical position monitoring without locking, compare [DX-D2/DX-D3](/products/safety-door-lock/dx-d2-and-dx-d3-safety-door-switch/). For non-contact monitoring, [DX-C1](/products/safety-door-lock/dx-c1-magnetic-coded-safety-switch/) uses coded magnetic actuation and [DX-R1](/products/safety-door-lock/dx-r1-non-contact-safety-switch/) uses RFID coding with dual-channel transistor outputs. For mechanical-contact guard locking, compare DX-W2, DX-W3 and DX-W5 by contact arrangement and holding force. [DX-D6](/products/safety-door-lock/dx-d6-guard-locking-safety-door-switch/) combines RFID-coded actuation, guard locking, redundant dual NPN or PNP outputs and a compact 30 × 30 mm metal body. It is the model-owned page for a compact electronic guard locking safety switch. Need | Starting family | Published distinction mechanical door-position monitoring | DX-D2 / DX-D3 | NC/NO contacts, no locking function magnetic non-contact monitoring | DX-C1 | coded magnet, up to 17 mm published sensing distance RFID non-contact monitoring | DX-R1 | universal or uniquely coded, dual NPN/PNP output mechanical-contact guard locking | DX-W2 / W3 / W5 | solenoid lock options and 1300 N published holding force compact electronic guard locking | DX-D6 | RFID actuator, 2000 N, 30 × 30 mm body ### How the DX-D6 Guard Locking Sequence Works DX-D6 separates three facts that are often confused: the actuator is present at the switch, the locking mechanism is engaged, and the redundant output signals are available to the safety controller. The controller evaluates those signals; the switch does not directly remove power from the machine load. C-type is mechanical lock with solenoid release (power-to-release). D-type is solenoid lock with mechanical release (power-to-lock). The correct loss-of-power behaviour depends on whether the machine retains a hazard after power is removed, so that choice belongs to the risk assessment rather than a generic preference. Figure context: Actuator present + lock state → redundant safety signals → safety controller; the controller owns the machine stop circuit. ### Magnetic, RFID or Mechanical Safety Switch? Magnetic coded switches tolerate guard misalignment and have no tongue entering a head. RFID-coded switches add universal- or uniquely-coded actuator choices and are useful where defeat resistance and electronic outputs matter. Mechanical tongue switches remain practical where visible positive actuation, conventional contacts and familiar maintenance procedures lead the specification. No technology is automatically correct for every door. Record door type, alignment movement, need for locking, desired coding, output style, ingress requirement and the safety function's required performance before selecting a model. ### From Door Switch to Safety Relay A door switch supplies the guard state; a safety relay or safety controller evaluates the safety channels and controls downstream contactors. The [DA31 safety relay module](/products/safety-relay/da31-emergency-stop-safety-relay-module/) includes a selectable safety-door input mode and accepts dual-channel PNP or NPN signals. The [safety relay category](/products/safety-relay/) compares DA31 with DQSRN. For exact terminal wiring, validate the switch variant, relay input mode and complete machine safety circuit together. Category text is not a substitute for the model wiring document or the machine risk assessment. Send the door type, whether the hazard coasts after stop, required holding force, coding preference and controller input type through the [inquiry form](/contact/). ### Order the Switch, Actuator and Release Arrangement Together Record the door swing or slide direction, mounting faces, actuator travel and required behaviour after loss of power. Separate position monitoring from actual guard locking: an actuator key or a door bolt alone is not an electronic safety switch. Item to agree on the quotation | Reference Electronic lock and matching coded actuator | [DX-D6 model and options](/products/safety-door-lock/dx-d6-guard-locking-safety-door-switch/) Mechanical actuator compatibility | [DX-K operation keys](/products/safety-door-lock/dx-k-series-safety-door-lock-operation-keys/) Door bolt and mounting arrangement | [DXL mechanical bolt](/products/safety-door-lock/dxl-safety-door-bolt/) Monitoring versus locking decision | [Safety-door selection guide](/guides/how-to-choose-a-safety-door-lock/) Request the exact certificate scope, circuit and permissible combination before safety validation. Do not transfer one DX family’s contacts, coding, force or release options to another. For robot cells, use the [sensor-role procurement checklist](/news/embodied-ai-robots-factory-sensor-role-selection/) to separate door access control from process measurement. ### Category FAQ Q: What is the difference between a safety interlock switch and a guard locking switch? A: An interlock switch monitors whether the guard is closed. A guard locking switch also holds the door shut until release is permitted. Q: When does a machine safety door need guard locking? A: Use guard locking when a hazardous condition can remain after the stop command, such as coast-down, stored pressure, heat or residual motion, and the risk assessment requires access to be delayed. Q: What is a magnetic safety switch used for? A: A magnetic coded safety switch monitors a movable guard without mechanical contact and can tolerate more alignment variation than a tongue-operated switch. Q: What is the difference between universal and uniquely coded RFID actuators? A: A universal-coded switch accepts the matching actuator type; a uniquely coded version recognises its paired actuator, increasing resistance to simple substitution. Q: Does DX-D6 directly switch the machine motor? A: No. Its redundant transistor outputs are evaluated by a safety controller or safety relay; downstream safety contacts or contactors remove power from hazardous functions. Q: How do I choose power-to-release or power-to-lock? A: Choose from the risk assessment and the safe state on loss of power. Consider whether a hazard remains after power-off and whether emergency escape or process protection must be maintained. ### DX-C1 Magnetic Coded Safety Switch URL: https://www.daidisensor.com/products/safety-door-lock/dx-c1-magnetic-coded-safety-switch/ DX-C1 non-contact magnetic coded safety switch: up to 17 mm sensing range, 2NC/1NC1NO/2NO outputs, IP65, ISO 13849-1 PLe Cat.4 circuit design, 6 models. - DX-C1 is a non-contact coded-magnet safety switch with a sensing distance of up to 17 mm in both the Z and Y directions. - DX-C1 requires multiple magnetically sensitive elements to be triggered in a defined sequence before it will actuate, distinguishing it from a simple reed-type magnetic door sensor. - DX-C1 is offered in three contact output configurations: 2 NC, 1 NC + 1 NO, and 2 NO. - DX-C1 is CE marked and designed for use in safety circuits up to Performance Level e, Category 4 under ISO 13849-1. ### DX-D2 & DX-D3 Safety Door Switch URL: https://www.daidisensor.com/products/safety-door-lock/dx-d2-and-dx-d3-safety-door-switch/ DX-D2 & DX-D3 mechanical safety door switches: NC/NO contacts, IP67 resin head, 1,000,000 mechanical / 300,000 electrical life, per IEC/EN60947-5-1. - The DX-D2/DX-D3 safety door switch is a mechanical contact-type interlock switch (NC/NO contacts) with no locking function. - Four ordering codes cover the DX-D2/DX-D3 range: DX-D2-CO (1NC+1NO), DX-D2-2C (2NC), DX-D3-2CO (2NC+1NO), DX-D3-3C (3NC). - The switch head is rated IP67 and made of resin. - Rated mechanical life is 1,000,000 operations; rated electrical life is 300,000 operations. ### DX-D6 Guard Locking Safety-Door Switch URL: https://www.daidisensor.com/products/safety-door-lock/dx-d6-guard-locking-safety-door-switch/ DX-D6 guard locking safety-door switch: 2000 N holding force, redundant dual NPN/PNP outputs, RFID-coded actuators, 30x30 mm metal body, 32 model variants. - The DX-D6 guard locking safety-door switch combines mechanical/electromagnetic door locking with independent redundant monitoring outputs in a single device. - The DX-D6 is available in a mechanical-lock/solenoid-release (power-to-release) C-type and a solenoid-lock/mechanical-release (power-to-lock) D-type, to match different machine risk-assessment outcomes. - The DX-D6 provides a rated holding force of 2000 N. - The DX-D6's all-metal body has a 30 mm × 30 mm cross-section, sized for direct mounting on aluminum extrusion frames up to 30 mm. ### DX-D6 Guard Locking and Monitoring Sequence DX-D6 performs two related jobs: it holds the guard closed and reports redundant state signals to the safety controller. The RFID actuator identifies that the door has reached the switch; the locking mechanism secures it; the controller evaluates the switch outputs before permitting hazardous motion. On a stop request, the machine must reach the release condition before the lock is released. This is a functional overview, not a timing or terminal diagram. Release logic, controller evaluation and the complete stop circuit must be validated from the exact C/D, R/H, S/D, N/P and A/B model ordered. Figure context: Door reaches actuator → lock engages → redundant state reaches the controller → machine permission is evaluated. ### Power-to-Release vs Power-to-Lock DX-D6 DX-D6 lock code | Published mechanism | Loss-of-power behaviour to assess C type | mechanical lock / solenoid release | power is required to release the guard D type | solenoid lock / mechanical release | loss of power releases the electromagnetic lock The selection is a risk decision, not a convenience preference. If hazardous motion or stored energy remains after power loss, the guard may need to remain locked; if emergency release is the dominant requirement, the safe behaviour may differ. Compare the other [safety door switches and guard locks](/products/safety-door-lock/) before fixing the architecture. ### DX-K Series Safety Door Lock Operation Keys URL: https://www.daidisensor.com/products/safety-door-lock/dx-k-series-safety-door-lock-operation-keys/ DX-K series operation keys: 11 models (DX-K1-K8, no K7) for DX-W2/W3/W5/D2/D3 safety door locks, ±1mm insertion tolerance, fixed and adjustable geometries. - The DX-K operation key series comprises 11 models (DX-K1, DX-K1D, DX-K2, DX-K2D, DX-K3, DX-K3D, DX-K4, DX-K4D, DX-K5, DX-K6, DX-K8); there is no DX-K7 in this numbering. - DX-K keys are designed to fit the DX-W2, DX-W3, DX-W5, DX-D2, and DX-D3 safety door lock/switch bodies. - The specified key-to-slot insertion tolerance is ±1mm. - Preparation clearance before fitting is 1~3.5mm for the DX-W2/W3/W5 switch family and 1~2.5mm for the DX-D2/D3 switch family. ### DX-R1 Non-contact Safety Switch (RFID Coded) URL: https://www.daidisensor.com/products/safety-door-lock/dx-r1-non-contact-safety-switch/ DX-R1 non-contact RFID-coded safety switch: dual-channel 150mA PLe, Type 4 (ISO 14119) output, 0-10mm switch-on, 60ms response, 8 NPN/PNP models, cascadable. - The DX-R1 non-contact safety switch has an assured horizontal switch-on distance of 0-10mm and an assured switch-off distance greater than 25mm. - Vertically, the DX-R1's assured switch-on distance is 0-6mm and assured switch-off distance is greater than 15mm. - The DX-R1 provides dual-channel solid-state (transistor) safety outputs rated 150mA, plus a separate 50mA auxiliary/diagnostic output. - The DX-R1 is available in 8 complete-set (P1) models, spanning 4-wire (F-type) and 6-wire cascade (E-type) wiring, NPN and PNP output, and universal (S) or unique (D) coding per ISO 14119. ### DX-W2 Safety Door Lock (Solenoid Guard Locking Interlock Switch) URL: https://www.daidisensor.com/products/safety-door-lock/dx-w2-safety-door-lock/ DX-W2 safety door lock: 1300 N holding force, 4 contact blocks in 14 NC/NO configurations (28 models), IP67, 24VDC solenoid, 1,000,000 mechanical cycles. - The DX-W2 safety door lock provides a rated holding force of 1300 N. - The DX-W2 solenoid operates on 24 V DC ±10%, consuming approximately 200 mA (4.8 W). - The DX-W2 is rated IP67 and offers a mechanical life of 1,000,000 operations with an electrical life of 150,000 operations. - The DX-W2 offers 14 NC/NO contact configurations across two independent contact compartments, available in two locking-release types (GD, GC), for 28 catalog models. ### DX-W3 Safety Door Lock URL: https://www.daidisensor.com/products/safety-door-lock/dx-w3-safety-door-lock/ DX-W3 safety door lock: 1300 N holding force, 2 gold-plated contact blocks in 6 NC/NO configurations, DC24V IP67, 1,000,000-cycle life, 12 model variants. - The DX-W3 safety door lock provides 1300 N of locking/holding force. - The DX-W3 is available in 12 models: 6 NC/NO contact combinations, each offered in GD and GC locking-type versions. - The DX-W3 uses 2 gold-plated contact blocks and is rated for 1,000,000 mechanical operating cycles. - The DX-W3 solenoid operates on DC24V ±10% and the switch is rated IP67. ### DX-W5 Safety Door Lock (Guard Locking Interlock Switch) URL: https://www.daidisensor.com/products/safety-door-lock/dx-w5-safety-door-lock/ DX-W5 safety door lock: 6 gold-plated contact blocks, 4 NC/NO configurations, GD/GC locking, 1300 N holding force, IP67, over 150,000 operations life. - The DX-W5 safety door lock provides six gold-plated silver-alloy contact blocks across four NC/NO configurations (2CO/2CO, 3C/2CO, 2CO/3C, 3C/3C). - DX-W5 holding force is rated at 1300 N. - DX-W5 is offered in eight order codes: four contact configurations, each available in GD (solenoid-locked, mechanically released) and GC (mechanically-locked, solenoid-released) versions, with a metal (J) head. - DX-W5 solenoid operating voltage is 24 V DC or 10-115 V AC/DC; indicator light voltage is 10-115 V AC/DC. ### DXL Safety Door Bolt (DXL-A / DXL-B) URL: https://www.daidisensor.com/products/safety-door-lock/dxl-safety-door-bolt/ DXL safety door bolt: purely mechanical, 48mm bolt travel, 1,000,000-cycle life, 1-10mm door gap tolerance, pre-drilled for DX-W2/W3/D2/D3 interlock switches. - The DXL safety door bolt has no electrical output of its own; it is a purely mechanical bolt with mounting provisions for a separate interlock switch. - DXL's base mounting pattern is designed to accept DAIDISIKE's DX-W2, DX-W3, DX-D2, and DX-D3 interlock switches directly. - DXL accommodates door gaps from 1 to 10 mm. - DXL has a bolt travel of 48 mm and a rated mechanical life of 1,000,000 operations. ## fiber-optic-sensor Category URL: https://www.daidisensor.com/products/fiber-optic-sensor/ ### Pair the Fibre Head with Its Amplifier and Mounting Task A fibre-optic sensing package may require a separate amplifier and optical head. Compare the task, available mounting space, fibre routing and receiving controller as one assembly. A fibre head alone is not a complete electrical sensor, and a head/amplifier combination must be confirmed before ordering. ### Compare the Configuration Paths Required task | Existing product page | What to confirm Electrical evaluation and teaching | [Digital fibre amplifier options](/products/fiber-optic-sensor/fiber-amplifier/) | Confirm supported heads, output type and required adjustment or teaching controls. Optical mounting at the target | [Fibre-optic head configurations](/products/fiber-optic-sensor/fiber-optic-sensor-heads/) | Choose sensing arrangement, tip geometry, fibre length and routing limits. Array-type optical arrangement | [Matrix fibre heads](/products/fiber-optic-sensor/matrix-fiber-optic-heads/) | Verify the actual target and compatible amplifier rather than treating an array as a safety curtain. ### A Complete Fibre-Sensor Bill of Materials Purchase input | Information to provide Head and amplifier | Record both order codes and the manufacturer-confirmed compatible pairing. Fibre routing | Include installed length, bend space, protection and service-access requirements. Target sample | Define the smallest feature, target surface, speed and required control signal. Compare [slot sensors](/products/slot-sensor/) if an integrated U-shaped body fits, or [miniature photoelectric sensors](/products/photoelectric-sensor/) for a self-contained electrical package. Send the application details and required configuration through the [inquiry form](/contact/) so that the quotation identifies the selected equipment and options. ### Fiber Amplifier (Digital Fiber Optic Sensor Amplifier) URL: https://www.daidisensor.com/products/fiber-optic-sensor/fiber-amplifier/ DAIDISIKE fiber amplifier series: digital fiber optic sensor amplifiers with NPN/PNP output, 4-step 25/50/200/400µs response time, and 35mm DIN-rail mounting. - The WAN/WAP dual-display fiber amplifier shows the preset threshold in green and the current received light intensity (0–9999) in red on two separate 8-digit rows. - The WAN/WAP model offers four selectable response-time steps: 25 µs, 50 µs, 200 µs, and 400 µs. - The WDN single-display fiber amplifier provides three power modes — FINE (200 µs), TURBO (400 µs), and SUPER (0.8 ms) — with a maximum system detection distance of 0–4000 mm. - The DA4-DAIDI Chinese-menu fiber amplifier has a documented response time of 16–25 µs. ### Fiber Optic Sensor Heads (Fiber Units) URL: https://www.daidisensor.com/products/fiber-optic-sensor/fiber-optic-sensor-heads/ Fiber optic sensor heads: passive through-beam, diffuse reflective, coaxial and array types, M3/M4/M6 sizes, four sleeve lengths, 1 m cable standard. - The fiber optic sensing head is a passive optical component; it contains no electronics, which are instead located in the separate fiber amplifier. - Standard through-beam (T), diffuse reflective (KS) and coaxial (RC) fiber head series share a common 310/410/610 (M3/M4/M6) sizing system with four optional sleeve lengths per size: 10, 20, 40 and 90 mm. - Right-angle (90 degree) head versions are available across the through-beam, diffuse reflective and coaxial series for low-profile, flush mounting. - Array (matrix) fiber units are available in through-beam (DK-KT series) and diffuse reflective (DK-KF series) configurations, each projecting light across a detection band rather than a single point. ### Matrix (Array) Fiber Optic Heads URL: https://www.daidisensor.com/products/fiber-optic-sensor/matrix-fiber-optic-heads/ Matrix (array) fiber optic heads cover a detection zone with multiple light points. DK-KT through-beam and DK-KF diffuse reflective series, 18 models. - 2 configurations: DK-KT through-beam series and DK-KF diffuse reflective series - 18 models in total: 9 per series, with 8 numeric-suffix sizes (10/15/20/25/30/35/50/120) plus one U10 model each - Compatible fiber amplifier platform rated for a system detection range of up to 4,000 mm, depending on fiber unit and power mode - Zero electronics at the sensing point - the head is a fully passive optical component ## safety-edge Category URL: https://www.daidisensor.com/products/safety-edge/ ### Compare Edge Profile, Active Length and Evaluation Method A pressure-sensitive edge detects contact along a moving edge. Its profile, mounting rail, end treatment, cable exit and evaluation interface belong to the selected system. It is not interchangeable with a floor mat or non-contact protective field. ### Compare the Configuration Paths Required task | Existing product page | What to confirm Pressure-sensitive profile configurations | [JB-PSE edge options](/products/safety-edge/jb-pse-series-pressure-sensitive-safety-edge/) | Compare profile geometry, active length, termination and compatible evaluation method. Alternative edge construction | [JB economy edge family](/products/safety-edge/jb-series-safety-edge/) | Check the exact profile and electrical arrangement before using another family’s dimensions or circuit. ### Information Needed Before Cutting or Ordering an Edge Purchase input | Information to provide Mechanical layout | Provide the moving-edge drawing, fixing method, usable profile space and required active length. Cable and joints | Identify cable-exit direction, end caps, bends and any joining arrangement. Evaluation and machine stopping | Confirm the monitored interface and controller compatibility; stopping performance requires machine-level validation. For floor-area occupancy instead of edge contact, compare [safety mats](/products/safety-mat/). For a non-contact opening, review [light-curtain configurations](/products/safety-light-curtain/). Send the application details and required configuration through the [inquiry form](/contact/) so that the quotation identifies the selected equipment and options. ### JB-PSE Series Pressure-Sensitive Safety Edge URL: https://www.daidisensor.com/products/safety-edge/jb-pse-series-pressure-sensitive-safety-edge/ JB-PSE pressure-sensitive safety edge: 13 ms response, PFH 6.99x10-10/h, Category 3, MTTFd >30 years, 7 profiles for AGV, door and machine protection. - The JB-PSE series pressure-sensitive safety edge has a response time of 13 ms and an actuating travel of less than 2 mm on the JB-PSE-108 and JB-PSE-110 profiles. - JB-PSE-360 provides overtravel of up to less than 45 mm, giving the connected machine additional braking distance after the stop signal is issued. - The JB-PSE series catalog lists a PFH of 6.99×10⁻¹⁰ per hour (referenced against IEC 61508, SIL 3), Category 3 per EN ISO 13849-1, MTTFd greater than 30 years, and B10d of 3×10⁷ when used with a DQRSN-SR(A) safety controller. - The JB-PSE series is available in seven cross-section profiles (108, 110, 215, 230, 245, 345, 360) mounted on 15 mm, 25 mm, or 35 mm aluminum rails. ### JB Series Safety Edge (Economy Line) URL: https://www.daidisensor.com/products/safety-edge/jb-series-safety-edge/ JB Series Safety Edge (Economy Line): 37 rubber cross-section profiles, 5-90 mm high, actuating force <=30 N, IP65, -20C to +80C, custom lengths 20-300 cm. - The JB series offers 37 rubber cross-section profiles ranging from 5 mm to 90 mm in height. - Catalog-listed JB safety edge models have an actuating force of 30 N or less and an actuating travel of 2 to 8 mm. - Up to 5 JB safety edges can be daisy-chained to a single controller input. - The 2-wire monitored version of the JB safety edge uses an 8.2 kΩ, 0.25 W terminating resistor for line supervision. ## contact-displacement-sensor Category URL: https://www.daidisensor.com/products/contact-displacement-sensor/ ### Order the Probe, Measuring Stroke and Readout as a System A contact displacement probe measures by touching the workpiece. Select the usable stroke, tip arrangement, mounting, return or actuation method and compatible readout before comparing a single precision figure. Family options must not be silently assigned to every individual model. ### Compare the Configuration Paths Required task | Existing product page | What to confirm Contact measurement configuration | [JNS-Q probe and controller options](/products/contact-displacement-sensor/jns-q-contact-displacement-grating-sensor/) | Identify the exact model, measuring stroke and whether the quotation includes a compatible display/control unit. ### Contact-Probe Purchase Checklist Purchase input | Information to provide Workpiece access | Provide approach direction, fixture drawing and the surface to be contacted. Model-specific performance | For the confirmed JNS-Q120, stroke is 12.7 mm and repeatability is ±2 μm; these are not interchangeable with resolution or absolute accuracy. Complete delivery | The display/controller is optional. Confirm the interface, tip/accessories and required controller on the order. Compare the [non-contact laser displacement families](/products/laser-displacement-sensor/) if touching the workpiece is unsuitable. Request the current JNS-Q model documentation for any parameter not stated for the selected version. Send the application details and required configuration through the [inquiry form](/contact/) so that the quotation identifies the selected equipment and options. ### JNS-Q Contact Displacement Grating Sensor URL: https://www.daidisensor.com/products/contact-displacement-sensor/jns-q-contact-displacement-grating-sensor/ JNS-Q contact displacement sensor: JNS-Q120 has 12.7 mm range and ±2 µm repeatability, with an optional display controller. Compare exact output and series options. - JNS-Q120 is confirmed with 12.7 mm measuring range and ±2 μm repeatability. The 0.2–5 μm catalogue resolution range describes family variants, not the Q120 repeatability or absolute accuracy. - The JNS-Q is available in two standard measuring ranges: 12.7 mm (JNS-Q120 series) and 25.4 mm (JNS-Q250 series). - RS232/RS485 and Modbus RTU are catalogue-listed options on relevant configurations. Confirm the exact voltage/interface, controller, protocol and supported network size; published software-device counts and bus-address capacity are not interchangeable. - O1/O2 limit-alarm signals are catalogue-listed configuration options for GO/NG evaluation. Confirm their presence, logic and load rating on the ordered probe/controller combination. ## safety-mat Category URL: https://www.daidisensor.com/products/safety-mat/ ### Specify the Protected Floor Layout, Not Just Mat Size Pressure-sensitive mat selection includes the floor area, access paths, joints, edge profiles, cable exits and evaluation system. A mat alone does not validate the machine stop function. Confirm the complete mat/controller combination and its applicable documentation for personnel protection. ### Compare the Configuration Paths Required task | Existing product page | What to confirm Floor presence-detection configuration | [JT14 mat and installation details](/products/safety-mat/jt14-safety-mat/) | Request the exact size, edge arrangement, cable routing and compatible evaluation documentation. ### Prepare a Mat Layout and Controller Request Purchase input | Information to provide Floor drawing | Mark dimensions, doors, equipment feet, mat joints and any route that could bypass the sensing area. Operating conditions | Describe expected loads and cleaning conditions. Conflicting load units or thickness figures require the current model drawing; do not convert unrelated catalogue claims. Safety function | Specify controller, reset/restart requirements and the required validation scope as a complete system. The [robot-cell selection checklist](/news/embodied-ai-robots-factory-sensor-role-selection/) separates presence detection from access guarding. Compare [safety edges](/products/safety-edge/) only for contact at a moving edge, not as an equivalent floor solution. Send the application details and required configuration through the [inquiry form](/contact/) so that the quotation identifies the selected equipment and options. ### JT14 Safety Mat (Economical) URL: https://www.daidisensor.com/products/safety-mat/jt14-safety-mat/ JT14 economical safety mat: ≥30 kg actuating force, ≤30 ms response, IP65 rating, 1,000,000-operation life, volt-free N.O. output, 6 sizes plus custom shapes. - The JT14 safety mat has an actuating force of ≥30 kg for an adult. - The JT14 safety mat has a response time of ≤30 ms. - The JT14 safety mat carries an IP65 protection rating. - The JT14 safety mat features an NBR rubber surface with aluminum trim edging and a mechanical life of 1,000,000 operations. # Engineering articles ## Embodied AI Robots Enter Factories in 2026: How Light Curtains, Guard Locks, Safety Laser Scanners and Displacement Sensors Divide the Work URL: https://www.daidisensor.com/news/embodied-ai-robots-factory-sensor-role-selection/ Published: 2026-08-29 A 2026 engineering guide to choosing light curtains, guard locks, safety laser scanners and displacement sensors for embodied AI robot cells. Content updated: 2026-09-06 Embodied AI — also called physical AI — is moving from research demonstrations into limited factory pilots. The important word is **limited**. The International Federation of Robotics says reliability, efficiency, safety and security are among the tests that industrial humanoids still have to pass. A smarter robot may adapt its path or learn a new handling task, but that intelligence does not automatically make the complete robot application safe. **Quick answer:** a [safety light curtain](/products/safety-light-curtain/) detects a person crossing a fixed open access point; a [guard locking switch](/products/safety-door-lock/) controls entry through a physical door and can hold it closed while danger remains; a [safety laser scanner](/products/lidar/st27-safety-laser-scanner/) monitors a configurable floor area; and a [laser displacement sensor](/products/laser-displacement-sensor/) measures the workpiece or process. The first three can participate in personnel-protection functions when correctly selected and integrated. The displacement sensor normally belongs to the production and quality loop, not the personnel-safety loop. That division of work is the central design rule. Do not ask which sensor is most advanced. Ask what hazard must be reduced, how a person can approach it, how long the complete machine takes to reach a safe state, and what diagnostic performance the safety function requires. ### Why 2026 Is a Turning Point — but Not Mass Adoption The [IFR's Top 5 Global Robotics Trends for 2026](https://ifr.org/ifr-press-releases/top-5-global-robotics-trends-2026) puts AI-driven autonomy, IT/OT convergence, real-world humanoid testing, safety and security on the same list. That combination matters: the robot is becoming less isolated from production data and more capable of changing its behaviour, while the case for deterministic protection and human oversight becomes stronger rather than weaker. The installed industrial-robot base is already large. IFR's World Robotics 2025 summary records approximately 542,000 new industrial-robot installations in 2024 and an operational stock of about 4.664 million units. Those figures describe industrial robots as a whole — not humanoids — and should not be misread as evidence that embodied robots are already common on every shop floor. The more honest signal comes from pilots. In [BMW Group's March 2026 production report](https://www.bmwgroup.com/en/news/general/2026/humanoid-robot-in-leipzig.html), a Figure 02 pilot ran for ten months, handled more than 90,000 components and supported production associated with more than 30,000 vehicles. BMW also says the trial led to revised safety concepts with additional barriers and partitions. The lesson is practical: physical AI can add flexibility, but real deployment still depends on conventional, engineered safeguarding. IFR's separate [Humanoid Robots: Vision and Reality](https://ifr.org/ifr-press-releases/news/humanoid-robots-vision-and-reality-paper-published-by-ifr) paper is equally careful. It says the timing of mass adoption is uncertain and expects humanoids to complement existing robots rather than replace them. This article therefore treats 2026 as a transition from prototype to controlled production use — not as permission to remove fences or trust AI perception as a safety function. **The headline that survives the hype:** Embodied AI may decide and adapt, but personnel protection still depends on a validated safety-related chain selected from the complete application risk assessment. ### The First Separation: AI Control, Safety Control and Process Measurement An embodied robot normally contains several perception and control layers. Cameras, ordinary LiDAR, force estimation and a vision-language-action model help it understand the scene and plan an action. Servo loops execute the movement. Process sensors confirm that the right part is present or that a dimension is within tolerance. Separately, safety-related inputs, logic and final switching elements must bring the hazardous application to a defined safe state when required. Google DeepMind's [Gemini Robotics description](https://deepmind.google/blog/gemini-robotics-brings-ai-into-the-physical-world/) makes a similar architectural distinction: high-level embodied reasoning can connect to low-level, embodiment-specific safety-critical controllers. In a factory risk assessment, that is not merely a software preference. The safety function needs defined behaviour, diagnostics, response time and validation. A probabilistic AI model that can re-plan a task should not be treated as the sole channel that decides whether a person is protected. The safety chain starts at a safety-related input and continues through the logic and the elements that actually remove or control hazardous energy. A normal PLC status bit is useful for diagnostics and production management, but it does not become a safety output because the AI reads it. Likewise, a displacement measurement can make the process more accurate without contributing any risk reduction for a person. ### Four Devices, Four Different Jobs The four product families in this article overlap visually — all of them sense something — but they answer different engineering questions. The table is the shortest useful comparison. Device | Primary question | Typical location | What it does not replace Safety light curtain | Did a person cross this fixed open plane? | Loading opening, transfer point, operator access | A physical guard against ejected parts, heat, radiation or a person remaining hidden inside Interlock / guard locking switch | Is the guard closed, and must it stay locked until danger ends? | Maintenance door or fenced-cell access gate | Presence detection across an open floor or inside the cell Safety laser scanner | Is a person entering or present in this two-dimensional floor field? | Open robot station, approach aisle, AGV/AMR perimeter | Finger/hand-resolution protection or containment of process hazards Displacement sensor | Is the part at the expected height, position or dimension? | Gripper station, fixture, inspection point, conveyor | A certified personnel-protection sensor or safety-rated stop chain ### 1. Safety Light Curtains: A Detection Plane Across an Open Access Point A safety light curtain is strongest where a production opening must remain physically open: a robot loading station, a part-transfer window or an operator interface. The emitter and receiver form a defined plane. When the specified test object interrupts the beams, the safety outputs change state and the downstream safety-related control system requests a safe stop. For a compact transfer opening, the [DQO product page](/products/safety-light-curtain/dqo-zero-blind-zone-safety-light-curtain/) is a catalogue example to investigate. It lists beam-pitch, height and housing data, but the exact output arrangement, remaining end blind zone, detection capability and safety evidence must be reconciled with the ordered version. A 'zero blind-zone' name and a family-level Type claim are not a machine-safety approval. The light curtain's response time is only one part of the separation-distance calculation. The integrator must include the safety logic, drive or valve response, robot and tooling stopping performance, and the applicable intrusion allowance. The maximum stopping time of the complete application must be measured and validated — not copied from a robot brochure. A curtain also cannot solve every access problem. If a person can pass through the plane and stand behind it, the design must address presence inside the safeguarded space, blind zones, reset location and prevention of unexpected restart. If the robot process can eject a part, produce welding radiation, heat or hazardous fluid, a physical enclosure remains necessary because an optical field contains nothing. Turn the opening requirements into a purchase shortlist with the [light-curtain selection guide](/guides/how-to-choose-a-safety-light-curtain/), keeping rated detection capability separate from beam pitch and confirming the evidence for the exact output version. - Use it for a frequently crossed, fixed opening where hazardous motion can stop before the person reaches the hazard. - Choose detection capability according to the reachable body part; beam pitch is not the same number as minimum detectable object size. - Measure the full stop time and position the field under ISO 13855:2024 and the applicable machine standard. - Design against reach-over, reach-under, step-through and a person remaining undetected inside the cell. ### 2. Interlocks and Guard Locking: Control the Door, Not the Floor A movable guard creates a different question. A safety interlock tells the safety-related control system whether the door is closed. Opening it must initiate the required safe response and prevent hazardous restart while the door remains open. Guard locking adds a second function: it physically holds the door closed until the risk from run-down, stored energy, gravity or another residual hazard has ended. The distinction matters in robot cells. If hazardous movement stops before a person can reach it, an interlocked guard may be sufficient after risk assessment. If the robot, spindle, turntable or heavy load continues moving after a stop request, opening the door immediately can still expose the person. That is when guard locking, safe release logic and an emergency/manual release strategy require careful design under ISO 14119:2024. The [DX-D6 guard locking safety-door switch](/products/safety-door-lock/dx-d6-guard-locking-safety-door-switch/) is the relevant DAIDISIKE model for the second case. Published product data states a 2000 N holding force, redundant monitoring outputs and two lock strategies: mechanical lock with solenoid release, or solenoid lock with mechanical release. The risk assessment must choose the appropriate strategy; power-to-lock and power-to-release are not interchangeable assumptions. Where the requirement is only non-contact coded door-position monitoring and no locking force is needed, the [DX-R1 non-contact safety switch](/products/safety-door-lock/dx-r1-non-contact-safety-switch/) is a different product class. Calling every door sensor a 'safety lock' hides a real design decision. Neither product detects a person who is already standing elsewhere inside the enclosure. Before ordering, use the [guard interlock and locking selection guide](/guides/how-to-choose-a-safety-door-lock/) to specify the lock strategy, actuator, output/connector and escape provisions. A door sensor does not replace measures for a person remaining elsewhere inside the cell. Access condition | Likely function | Design question Hazard reaches a safe state before access is possible | Guard interlocking | Does opening reliably request the safe state and prevent restart? Hazard remains after the stop request | Guard locking plus interlocking | When may the door be released, and what happens on loss of power? Person can be trapped or hidden inside | Additional presence / escape / reset measures | How is unexpected restart prevented after entry? ### 3. Safety Laser Scanners: Flexible Protective Fields on the Floor A safety laser scanner is the natural choice when the protected geometry is an area rather than a line. It repeatedly measures the position of objects across a two-dimensional scan plane and compares them with configured fields. On an open robot station this can support approach detection or presence sensing; on a mobile platform it can support speed-dependent protective fields, subject to the applicable mobile-robot standard and verified braking performance. The [ST27 safety laser scanner](/products/lidar/st27-safety-laser-scanner/) is the safety-rated owner in this catalogue. Its published data states Type 3 under IEC 61496, SIL 2, Category 3 / PL d, a 276-degree scan, 3 m or 5 m protective-field variants at low target remission, 70 mm object resolution at the maximum protective radius, and variants with PNP OSSD outputs. These numbers are useful inputs; they do not by themselves validate the complete robot application. Protective and warning fields must not be confused. The ST27 warning range is useful for alerts or ordinary process actions, but its product data explicitly says the warning and measuring ranges are not safety functions. A person entering the validated protective field is what must produce the defined safety response. Field switching, reference boundaries, mounting height, occlusion, worst-case clothing remission and the complete stop distance all require application-level verification. The same distinction applies to the robot's own LiDAR. The [DLD-50D navigation and mapping LiDAR](/products/lidar/dld-50d-2d-tof-lidar-for-navigation-and-mapping/) produces Ethernet point-cloud data for localization and obstacle mapping. It is useful perception equipment, but it has no published personnel-safety rating and must not be substituted for ST27 in a safety function. Shared optical vocabulary does not create shared functional-safety capability. The [LiDAR selection guide](/guides/how-to-choose-a-lidar-scanner/) compares ordinary interfaces and target conditions with the separate safety-scanner decision. Keep protective, warning and measurement distances in distinct quotation fields. ### 4. Displacement Sensors: Process Feedback, Not Personnel Protection The fourth device is deliberately different. A laser displacement sensor measures the workpiece rather than the person. In an embodied-robot station it can confirm that a bin, casting, battery module or fixture is at the expected height before the robot commits to a grasp. It can measure thickness, gap, runout, step height or assembly seating and send a continuous value to the PLC, robot controller or quality system. The [DDK-G laser displacement sensor](/products/laser-displacement-sensor/gdk-series-laser-displacement-sensor/) is a non-contact example with five reference-distance grades from 30 to 250 mm, resolution beginning at 2 micrometres under the published test conditions, and analog or RS485 variants. That makes it useful for robot positioning and in-line quality checks. It does not make DDK-G a personnel-protection device. Where contact measurement suits the target, the [JNS-Q contact displacement sensor](/products/contact-displacement-sensor/jns-q-contact-displacement-grating-sensor/) is an alternative to investigate. Confirm the exact probe's stroke, resolution, accuracy and interface rather than treating family figures as interchangeable; the confirmed Q120 configuration has a 12.7 mm stroke and ±2 micrometre accuracy. It remains a process-measurement device, not a personnel safeguard. This boundary is explicitly consistent with IEC 61496-3:2025, whose scope excludes devices that perform only a single one-dimensional spot-like distance measurement. The safety laser scanner protects people; the displacement sensor verifies the process. Both may measure distance, but they do not perform the same function. - Use laser displacement for non-contact height, gap, thickness, alignment or runout measurement. - Use contact gauging when surface reflectivity makes an optical result difficult and physical contact is acceptable. - Send measurement values to ordinary control or quality systems; do not count them as personnel risk reduction without a safety-rated product and validated safety function. - Define the target material, surface, reference distance, required resolution, cycle time and interface before choosing the model. **One sentence worth putting on the design review:** A process sensor may help the robot avoid an error; a safety function must protect a person even when ordinary control, communication or AI behaviour fails in a reasonably foreseeable way. ### Worked Example: An Embodied Robot Loads a Machine Consider a humanoid-style or mobile manipulator loading cast components into a fixed machining station. The robot receives a production order, identifies the part, picks it and presents it to a fixture. The useful design is not 'one smart sensor'. It is a set of boundaries aligned to how people and material move. At the transfer opening, a safety light curtain detects a person crossing the fixed plane. At the maintenance gate, a guard-locking switch prevents release until the robot and connected machine have reached the safe state defined by the risk assessment. A safety laser scanner covers an open approach or a floor area where a person could enter around the transfer path. A displacement sensor checks the raw part height and seating position before machining begins. The AI can decide which component to pick and can re-plan after a failed grasp. The displacement sensor can tell it that the component sits 1.2 mm too high. Neither signal is the personnel-protection decision. If a person breaks the light curtain, opens the gate or enters the protective scanner field, the independent safety-related control system must produce the specified stop regardless of what the AI intended to do next. - Production state: AI plans the move; displacement sensing verifies the part and fixture. - Material transfer: the opening safeguard is designed so valid material flow does not create an unsafe bypass. - Human intrusion: the appropriate safety sensor changes state and the safety logic commands the defined safe response. - Maintenance entry: the door is released only under the validated conditions, and restart requires a deliberate procedure with a clear view of the safeguarded space. - Recovery after a fault: the operator uses the documented safe mode and enabling/control measures; the AI does not improvise a restart. ### What the Safety Chain Must Do After Detection A protective sensor does not stop a robot by itself. Its outputs enter safety-related logic, which evaluates the channels and commands the final elements that control hazardous energy. Those elements may be drive safety functions, redundant contactors, monitored valves or another architecture justified by the required performance level. The complete function — input, logic and output — is what ISO 13849-1:2023 asks the integrator to design and evaluate. For a compact fixed application, the [DA31 safety relay module](/products/safety-relay/da31-emergency-stop-safety-relay-module/) is a relevant logic example. Its published data includes dual-channel PNP/NPN input modes for an emergency stop, light curtain, door interlock or two-hand control, plus forcibly guided relay contacts and a separate status output. The status output can inform an ordinary PLC without making the PLC the safety decision maker. A scanner application with multiple field sets, safe speed selection or mode-dependent logic may require a suitable safety controller or safety PLC rather than a simple relay. The correct architecture comes from the safety-requirements specification. Do not add unverified reset, EDM or field-switching functions to a product simply because the overall application needs them. For the relay choice, the [documented safety-relay comparison](/products/safety-relay/) separates available input and contact arrangements. DQSRN supports manual and automatic reset per its selected-model instructions; EDM capability remains unconfirmed. Allocate and validate the required restart and final-element monitoring functions using the exact device and circuit documentation. Stage | Engineering question | Evidence to retain Input | Does the selected device detect the defined person, door or field condition? | Exact model, type/rating, configuration, response time and test record Logic | Does the safety relay/controller diagnose faults and execute the required reset/mode logic? | Safety-requirements specification, wiring, configuration and validation results Output | Does the drive, contactor or valve reach and maintain the defined safe state? | Measured stopping performance and final-element diagnostics Application | Can a person reach, bypass, remain inside or restart unexpectedly? | Risk assessment, layout, separation-distance calculation and periodic inspection plan ### A Practical Selection Worksheet for the Integrator Start with the task and access geometry. The following questions keep a project from buying several plausible devices and discovering during commissioning that none covers the actual route into danger. For a quotation, separate the safety-device shortlist from the process-measurement bill of materials. Include each exact output version, cable/connector, actuator or mounting accessory and requested document revision; the application layout alone does not identify a complete order code. Question | Likely device family | What must still be verified Must people frequently cross a fixed open access point? | Safety light curtain | Detection capability, stop time, separation distance, bypass and restart prevention Is access through a physical gate? | Safety interlock | Coding/defeat resistance, safe stop and prevention of unexpected restart Does dangerous motion continue after the stop request? | Guard locking switch | Lock strategy, release condition, escape/manual release and residual energy Is the approach an open or variable floor area? | Safety laser scanner | Protective field, resolution, occlusion, field switching and measured braking/stopping distance Does the robot need part height, gap or position feedback? | Laser/contact displacement sensor | Target surface, measuring range, resolution, response time and process interface Can people enter and remain hidden inside the safeguarded space? | Additional presence / trapped-person / reset measures | Whole-space coverage, escape, lockout and restart procedure Can the process eject, burn, irradiate or spray? | Physical guard or enclosure plus interlocking | Containment and the applicable process-specific standard ### Standards Map: Which Document Answers Which Question? No standard number is a substitute for the exact text or for local legal requirements. This map only shows where an integrator normally starts. Standard | Primary scope in this design ISO 12100:2010 | Hazard identification, risk assessment and the risk-reduction process for the complete machine ISO 10218-1:2025 | Safety requirements for the industrial robot as partly completed machinery ISO 10218-2:2025 | Integration, commissioning, operation and maintenance of industrial robot applications and cells ISO 13849-1:2023 | Design and integration of the safety-related parts of the control system ISO 13855:2024 | Positioning and dimensioning safeguards relative to human approach IEC 61496-2:2020 | Active opto-electronic protective devices such as safety light curtains IEC 61496-3:2025 | Diffuse-reflection electro-sensitive protective devices such as safety laser scanners ISO 14119:2024 | Selection and application of guard interlocks and measures to minimize defeat **Scope warning for mobile and dynamically balancing robots:** Do not assume every product marketed as an embodied or humanoid robot fits one standard in the same way. A fixed industrial robot cell, an industrial truck/AMR, a mobile manipulator and an actively balancing biped can have different and overlapping scopes. Classify the actual machine and application before selecting the standards. ### Common Design Mistakes to Reject Before Commissioning Most serious failures in a layered robot cell are category errors: a useful function is mistaken for a safety function, or one boundary is expected to cover a different geometry. - Treating the robot's cameras or navigation LiDAR as a certified protective device because the robot can avoid obstacles during a demonstration. - Using a scanner warning field as though it were the validated protective field that commands the safe response. - Counting a displacement sensor's part-presence output as personnel risk reduction. - Specifying a non-locking interlock where residual hazardous motion continues after the stop request. - Installing a light curtain at a convenient mechanical position without measuring the complete maximum stopping time. - Ignoring a person who can step through the opening, move behind the detection plane and remain inside the cell. - Routing a safety sensor through an ordinary PLC task and assuming duplicated software tags create safety integrity. - Using product family claims instead of the exact ordered model's manual, certificate scope and configuration record. - Allowing an automatic reset or AI-initiated restart when the safeguarded space cannot be fully observed and verified clear. ### Evidence and Scope of This 2026 Review This article uses first-party industry reporting and the current published standard editions rather than predictions copied from general media. The main references are listed here so an integrator can verify the scope and publication status. - [IFR — Top 5 Global Robotics Trends 2026](https://ifr.org/ifr-press-releases/top-5-global-robotics-trends-2026): AI/autonomy, humanoid reliability, safety and security trends. - [IFR — World Robotics 2025](https://ifr.org/worldrobotics/report-2025): global industrial-robot installation and operational-stock figures. - [BMW Group — humanoid production pilot report, March 2026](https://www.bmwgroup.com/en/news/general/2026/humanoid-robot-in-leipzig.html): limited production deployment and revised barrier concepts. - [Google DeepMind — Gemini Robotics](https://deepmind.google/blog/gemini-robotics-brings-ai-into-the-physical-world/): embodied reasoning and layered safety from high-level semantics to low-level controllers. - [ISO 10218-1:2025](https://www.iso.org/standard/73933.html) and [ISO 10218-2:2025](https://www.iso.org/standard/73934.html): industrial robot and integrated robot-application safety scopes. - [ISO 13849-1:2023](https://www.iso.org/standard/73481.html), [ISO 13855:2024](https://www.iso.org/standard/80590.html) and [ISO 14119:2024](https://www.iso.org/standard/75942.html): safety-related controls, safeguard positioning and guard interlocking. - [IEC 61496-2:2020](https://webstore.iec.ch/en/publication/63117) and [IEC 61496-3:2025](https://webstore.iec.ch/en/publication/84133): safety light-curtain and diffuse-reflection protective-device scopes. **Engineering disclaimer:** This article provides general engineering information and does not constitute a machine risk assessment, safety-system design, compliance certification or commissioning instruction. Required safety functions, PLr/SIL, protective-device type, separation distance, stopping time, reset logic, guard locking, muting and validation must be determined for the complete application by a qualified safety professional under the applicable laws, standards and exact product documentation. A standard displacement sensor is a process-measurement device and must not be used as the sole means of personnel protection. ### Article FAQ Q: Can an embodied AI robot's own cameras or LiDAR replace a safety scanner? A: Not unless the exact sensing subsystem and complete safety function are specifically designed, rated and validated for personnel protection. A navigation camera or LiDAR normally supplies perception data to ordinary robot control. A safety laser scanner is designed under the IEC 61496 protective-device framework, provides defined safety outputs and is integrated into a validated stop chain. Similar optics do not make the functions equivalent. Q: When should a robot cell use a light curtain instead of a safety laser scanner? A: Use a safety light curtain when the access geometry is a fixed plane and finer hand or finger detection may be required, such as a loading opening. Use a safety scanner when the protected geometry is a two-dimensional floor area, the approach direction varies or fields must match different operating states. Some applications need both. Selection and positioning must follow the risk assessment and measured stopping performance. Q: What is the difference between a safety interlock and guard locking? A: An interlock monitors whether a movable guard is closed and prevents hazardous operation when it is open. Guard locking additionally holds the guard closed until the release conditions are satisfied. Guard locking is commonly needed when hazardous movement or stored energy persists after the stop request. The required lock strategy and escape/manual-release measures depend on the complete application. Q: Can a laser displacement sensor be used for machine safety? A: A standard laser displacement sensor is a process-measurement device, not a personnel-protection device. It can confirm part height, position, gap or assembly quality and may request an ordinary process stop, but its output must not be counted as personnel risk reduction unless the exact product and complete safety architecture have the applicable safety rating and validation. The DAIDISIKE DDK-G and LK-F families are presented as process sensors. Q: Does installing these four devices make a robot cell compliant with ISO 10218? A: No. Compliance applies to the complete robot application, not a shopping list. The integrator still has to identify hazards, define the required safety functions and performance, select exact devices, measure stopping time, calculate safeguard position, design restart and access logic, validate the safety-related control system and document the result under the applicable standards and laws. Q: Do collaborative or humanoid robots still need guarding? A: They may. 'Collaborative' describes an application and its validated operating method, not a promise that every task is safe without guarding. Tooling, payloads, sharp edges, heat, stored energy, unexpected motion and the robot's full dynamic envelope all belong in the risk assessment. Limited 2025-2026 production pilots continue to use conventional barriers and controlled work zones. Q: Where does a safety relay fit in an embodied robot cell? A: A safety relay or safety controller evaluates compatible safety inputs and commands the final elements that create the safe state. A compact relay can suit a simple fixed function; applications with multiple scanner fields, safe speed or complex modes may require a safety PLC/controller. The ordinary PLC may receive status for diagnostics, but status reporting must not silently become the only safety decision path. Q: What information should I send when requesting sensor selection help? A: Send the robot or machine type, a layout with each human and material access route, the hazard and required safe state, measured maximum stopping time, opening or floor-zone dimensions, required detection capability, door run-down or stored-energy condition, workpiece material and measurement range, controller interface, environment and destination market. DAIDISIKE can help shortlist devices; the machine integrator remains responsible for the risk assessment and validation. ## Press Brake and Punch Press Light Curtain Guarding: What Actually Fails on the Factory Floor URL: https://www.daidisensor.com/news/press-brake-punch-press-light-curtain-guarding/ Published: 2026-07-26 Press and press-brake guard selection: five integration risks, detection-capability checks, limited distance arithmetic, and a qualified-verification checklist. Content updated: 2026-09-06 A fitted light curtain does not, by itself, prove that a press is safeguarded. The stop path, stopping performance, detection capability, access geometry and operating modes all affect the result. A buyer needs evidence for those decisions as well as an order code. This article is a purchasing and design-review checklist, not a published incident study or a report of verified customer assessments. The numerical examples below are hypothetical and explicitly limited to historical arithmetic; a qualified integrator must determine the current applicable installation requirements. Keep the distinction between sensor and safety function clear: an indicator changing colour is not proof that hazardous motion stops in time. Where protection is absent, defeated or uncertain, do not rely on it for production; follow the site's safe isolation and escalation procedure. ### The short answer: what a correctly guarded press looks like Before selecting equipment, request evidence for the complete safeguarding arrangement. The following questions apply to the review; they are not a declaration that every press can be made compliant by fitting the same light curtain. Document who is responsible for each item and which machine, tool setup and operating mode it covers. Physical tests belong to competent personnel following an approved safe procedure, not to an untrained buyer walking up to a running machine. - The protective device and complete safety function meet the required performance and applicable machine rules; ordinary measuring or photoelectric sensors are not substituted for personnel safeguards. - The exact output and controller arrangement commands the required safe response through the final switching elements. - Positioning is based on the applicable method, actual detection capability and measured maximum stopping performance for the relevant machine conditions. - Rated detection capability is recorded separately from beam pitch; protective height and arrangement cover all relevant approaches. - Reach-over, reach-under, side/back access and a person remaining behind the detection field are addressed. - Required diagnostics, reset/restart prevention and—where the machine rules require it—brake monitoring are documented and validated. - Production, setup, fault recovery and maintenance have approved modes and procedures; no uncontrolled bypass is needed to perform the task. ### Why Press Guarding Needs a Task-by-Task Review Presses, press brakes and shears can expose people to closing tools, moving stock and other hazards during repetitive work. The relevant question is not which machine has the highest incident percentage, but how a person can reach the actual hazard in each task. No traceable original source was established for the accident percentages previously printed here. They are not used as evidence in this review. Instead, identify the intended operation, foreseeable misuse and required risk-reduction measures for the particular installation. For United States applications, [OSHA 1910.212](https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.212) addresses general machine guarding. [OSHA 1910.217](https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.217) has specific mechanical-power-press requirements and expressly excludes press brakes and certain other machines from that section. Do not transfer its detailed provisions automatically to every forming machine. Setup, tool changes, clearing faults and maintenance can require different protective measures from normal production. Specify safe access, isolation, mode selection and responsibility for those tasks before the equipment is purchased. **Why this matters for how you buy:** Request a task and mode list, access layout, safe-stop requirements, current circuit information and stopping-time evidence. These records are more useful for selecting a guard than an unsupported accident percentage or a generic compliance claim. ### Five Integration Failure Patterns to Check These are qualitative review categories, not a frequency-ranked field survey. Their presence or absence must be established from the actual machine and its records. **Pattern 1 — A sensor indication without a validated stop path.** Confirm how the protective output reaches the logic and final elements, and how the hazardous condition is brought to a safe state. A lamp, buzzer or normal PLC input alone does not demonstrate that safety function. **Pattern 2 — Defeat or an uncontrolled bypass.** Review whether tooling, material flow or maintenance encourages an operator to bypass the device. Provide an approved safe method for the task and controlled access to configuration. Do not treat blanking or muting as a way to hide an unresolved access problem. **Pattern 3 — A mounting position without stopping-performance evidence.** Mechanical convenience does not establish separation distance. Retain the relevant maximum stop-time measurements and approved calculation, and reassess changes to tooling, loading, brakes, valves or operating modes. **Pattern 4 — Detection capability confused with beam pitch.** A 14 mm pitch is not necessarily a 14 mm detectable object. Use the exact documented test-object size, account for configuration changes and review every accessible route. **Pattern 5 — Required fault detection or restart measures absent.** Establish how failures in the final elements are diagnosed and how unexpected restart is prevented. The necessary measures depend on the required performance and machine rules; a generic 'safety relay' label does not prove they are present. ### Safety Distance: Limited Historical Arithmetic, Not an Installation Design The underlying question is whether the complete application reaches a safe state before a person can reach the hazard. Current installation decisions need the applicable standard edition, machine requirements, actual approach geometry and measured stopping performance. The arithmetic below illustrates only the legacy ISO 13855:2010 perpendicular-approach method for detection capability d from 14 to 40 mm. [ISO 13855:2010](https://www.iso.org/standard/42845.html) has been replaced by [ISO 13855:2024](https://www.iso.org/standard/80590.html). These examples are not approved separation distances for a new or existing machine. **Historical example: S = K × T + C, with C = 8 × (d − 14).** T is in seconds and d is the rated detectable-object size, not beam pitch. For this limited method, start with K = 2000 mm/s and a 100 mm minimum. If the first result exceeds 500 mm, the 1600 mm/s recalculation has a 500 mm floor. **T** must represent the relevant complete response to the safe state. A delay budget can include the sensor, safety logic and final-element/machine stop, but a measured total must not have the same delay counted twice. Allowances for deterioration and uncertainty must follow the applicable method rather than an arbitrary fixed margin. **Hypothetical example 1.** Assume 10 ms sensor, 15 ms logic and 165 ms machine-stop contributions: T = 0.190 s. For d = 30 mm, C = 128 mm. The first result is 508 mm; the historical recalculation is 432 mm, so its 500 mm floor governs the arithmetic. **Hypothetical example 2.** Assume d = 14 mm and T = 0.115 s. The same limited arithmetic gives 230 mm. This is a separate assumed input set, not evidence of a measured machine improvement or proof that a particular series detects fingers. The examples show sensitivity to input assumptions. They omit reach-over, reach-under, step-through, whole-body/multi-beam arrangements, other approaches, machine-specific requirements and additional checks in the applicable current edition. Do not shorten an installed distance using this table. North American requirements must be selected for the actual machine and operating mode. OSHA mechanical-press provisions and their PSDI provisions are not interchangeable, and neither is a universal press-brake formula. Retain the integrator's applicable rule, calculation and validation record. Rated detection capability d | C = 8 × (d − 14) | Initial 2000 × T + C | Historical result with applicable floor 14 mm | 0 mm | 380 mm | 380 mm 20 mm | 48 mm | 428 mm | 428 mm 30 mm | 128 mm | 508 mm | 500 mm 40 mm | 208 mm | 588 mm | 512 mm >40 mm / other geometry | Outside this example | Not calculated | Separate applicable method required **Before a mounting distance can be accepted:** Obtain the dated maximum stopping-time record, model-specific detection capability, layout, operating-mode assumptions and the qualified integrator's current-method calculation. No numerical result in this article authorises commissioning. ### Press Brakes: Match the Safeguard to the Bending Task Press-brake safeguarding depends on tooling, stock support, hand position, ram behaviour, operating modes and access from every side. Do not assume all arrangements suitable for a punch press transfer to bending. A fixed vertical light curtain can be appropriate in an assessed arrangement, but some hand-feeding tasks may conflict with the required sensing plane or separation distance. That conflict must be resolved by an appropriate safeguarding design, not by uncontrolled blanking or a blanket rule that fixed curtains are always forbidden. A ram-associated laser guard is another product arrangement to evaluate. DKE-L3 is described as a transmitter/receiver three-beam system; do not infer that it is an AOPDDR under IEC 61496-3 simply because it uses a laser. Request its actual optical principle, applicable device standard, safety evidence and controller-specific muting/field functions. Compare it with the alternatives in [press and press-brake protection](/products/press-brake-protection/). For box or complex bending, confirm whether the selected system supports the required field changes, under what conditions they are permitted, and how full protection is restored. A sales description cannot replace the exact configuration and validation instructions. Rear and side access need their own protective measures. The [DQV double-sided protection arrangement](/products/press-brake-protection/dqv-double-sided-photoelectric-safety-protection-device/) is a catalogue option to investigate alongside fixed guarding and interlocked access; its applicability and complete circuit must be verified. Include the pedal/control arrangement, setup and recovery modes, tooling clearances and the risk from the moving workpiece in the specification. An optical device does not remove every hazard arising during bending. ### What to specify for a punch press or shear DQS is a catalogue option for a curtain-and-controller arrangement. Specify the exact sensor, controller, output version and machine interface together; buying a set does not eliminate integration or validation work. Use the following table to request order-specific evidence. Published catalogue values are not a blanket confirmation of every option or an independent certification. Check the configured maximum response of the whole arrangement, not just the sensor's headline figure. Do not assume EDM or reset features from the controller family name; obtain the actual function and circuit documentation. The [DQC product page](/products/safety-light-curtain/dqc-general-safety-light-curtain/) includes specific output and detection limitations. The [DQT4 product page](/products/safety-light-curtain/dqt4-type-4-safety-light-curtain/) distinguishes 7.5/15/30 mm pitch from 14/21/36 mm detection capability. Neither link approves a press application. The [safety-relay comparison](/products/safety-relay/) supports input/contact review; DQSRN supports manual and automatic reset per its selected-model instructions; EDM capability remains unconfirmed. The [light-curtain selection guide](/guides/how-to-choose-a-safety-light-curtain/) covers opening and detection choices, while the [Type 2/Type 4 purchasing evidence checklist](/guides/type-2-vs-type-4-safety-light-curtains/) covers claim verification. The [video library](/solutions/video-cases/) is explanatory material, not validation of the viewer's machine. Parameter | DQS series Safety evidence | Request exact sensor/controller version, applicable Type/PL evidence and certificate or test scope Beam pitch | 10 / 14 / 20 / 25 / 30 / 40 / 80 mm catalogue choices; obtain detection capability separately Response | Catalogue sensor figure ≤10 ms; verify controller and complete configured response Sensing range | 0.3–3 m up to 0.3–40 m, selected by order code Output and control functions | Confirm exact relay/transistor arrangement; do not assume reset or EDM Controller contact rating | AC 250 V / 5 A or DC 30 V / 5 A Supply | Sensor DC 12/24 V; controller AC 110–220 V ±15% Enclosure | Published IP65; verify actual conditions, connectors and cleaning process Housing section | Approx. 35 × 51 mm **Specify the controller, not just the curtain:** Put the sensor, selected controller, final-element interface, required diagnostics, reset/restart functions and delivery documents on the same purchase specification. Leave unsupported functions as open items; do not order on an assumed compatibility. ### A 12-Point Evidence Checklist for Qualified Verification This checklist helps the buyer request commissioning evidence. It is not permission to approach, interrupt or modify a running machine. Testing requires competent personnel, an approved safe procedure, appropriate equipment and control of hazardous energy. Inspection and measurement intervals follow the machine instructions, risk assessment and applicable requirements. Revalidation after relevant changes is separate from routine checks; a universal annual schedule is not sufficient for every press. Additional hazards may require different devices: [safety edges](/products/safety-edge/) detect contact at a moving edge, and [safety mats](/products/safety-mat/) can support presence detection where correctly designed. Their selection and controller compatibility need the same evidence discipline. - **1. Safe-response test record.** Qualified personnel must validate the specified stop under a controlled procedure, using the manufacturer-prescribed test object—not a hand or body. - **2. Complete circuit.** Identify input, logic, final switching elements and the safe state; confirm status indication is not the only response. - **3. Defeat review.** Document and resolve unapproved bypasses and configuration changes under controlled access. - **4. Access assessment.** Check drawings and safely isolated equipment for reach-over, under, around, behind and tool-change access; never attempt reach tests at a live hazard. - **5. Stopping performance.** Obtain dated maximum measurements, conditions and the applicable separation-distance calculation. - **6. Actual positioning.** Compare the measured installation with the approved layout and calculation. - **7. Detection capability.** Verify the rated test-object size and any blanking/configuration effect separately from beam pitch. - **8. Coverage.** Confirm the full reachable opening and the risk of a person remaining behind the field. - **9. Diagnostics.** Retain validation of required final-element monitoring using an approved test procedure; do not improvise a welded-contact simulation. - **10. Machine-specific functions.** Verify required clutch/brake control, brake monitoring and other provisions for the actual machine and mode. - **11. Reset and restart.** Verify deliberate procedures, location, visibility and prevention of hazardous unexpected restart. - **12. Non-production tasks.** Record the approved isolation, setup, maintenance and recovery arrangements so the task does not depend on an uncontrolled bypass. ### Evidence to Request From the Supplier and Integrator A supplier's useful contribution is a traceable model and configuration record, not an unsupported claim that a particular installation was audited or made safe. Request the exact sensor/controller manuals, output drawing, detection capability, response limits, available safety data and certificate scope. Ask the machine integrator for the risk assessment, safety-requirements specification, stop-time measurements, positioning calculation and validation record. This article does not assert participation in a government programme, a measured frequency of factory defects or customer assessment results without traceable project records. Those claims from the earlier version have not been used as evidence for the current recommendations. The retained workshop photographs are context material, not customer endorsements or proof of completed assessments. Any future named case study needs verified project facts and permission before publication. ### Scope, limits and honest caveats Safety devices reduce risk. They do not eliminate it, and no supplier — including us — can promise that fitting a light curtain makes a machine safe. What determines the outcome is the risk assessment, the integration into the stop circuit, the calculated mounting distance, and the maintenance regime behind all three. Nothing in this article replaces a risk assessment under ISO 12100 for your specific machine, or the determination of the required Performance Level under ISO 13849-1 (or SIL under IEC 62061) that follows from it. The formulas here are given so that you can ask your integrator informed questions, not so that you can skip the calculation. Use the laws and machine-specific standards applicable to the location, machine type, manufacture/modification date and operating mode. [ISO 16092-1:2017](https://www.iso.org/standard/55667.html) is a starting scope reference for relevant presses, with further parts for specific press types; it is not a universal rule for every press brake or shear. Check current editions and national adoption before applying a provision. Ordinary measuring curtains, DD/DDOF area sensors and general-purpose obstacle LiDAR must not be counted as personnel safeguards. For a protective device, request suitable exact-model evidence and validate its role in the complete function. The [IEC 61496-3:2025 scope](https://webstore.iec.ch/en/publication/84133) concerns diffuse-reflection protective devices; a laser transmitter/receiver pair does not acquire that classification merely by being optical. ### Article FAQ Q: Does a safety light curtain on a press have to be interlocked with the machine control system? A: A protective device must be integrated into a validated safety function that achieves the required safe state; an indicator or normal PLC status input alone is not sufficient. Check the exact output, controller and final elements against the applicable machine requirements. This is a design obligation, not a claim about the frequency of field failures. Q: How do I calculate the safety distance for a light curtain on a punch press? A: Use the applicable current standard method, actual detection capability, approach geometry and measured maximum stopping performance of the complete function. The numerical table in this article is a limited historical ISO 13855:2010 perpendicular-approach illustration for d=14–40 mm, not an installation calculation. ISO 13855:2024 supersedes that edition, and machine-specific or regional requirements must be assessed separately. Q: Why can't I just fit a normal vertical safety light curtain to a press brake? A: The answer depends on tooling, hand position, operating mode, stopping performance and applicable machine requirements. A fixed curtain may suit an assessed arrangement; another task may require a ram-associated laser guard or different measures. Do not use uncontrolled blanking to make an unsuitable arrangement work. DKE-L3's exact optical classification, controller functions and safety evidence must be verified rather than inferred from the word laser. Q: What resolution should a light curtain have for press guarding — 14 mm, 30 mm or 40 mm? A: Select by rated detection capability and access geometry, not pitch or price. Current DQC data distinguishes 10/14 mm pitch from 18/22 mm detectable objects; DQT4 lists 14/21/36 mm detection for 7.5/15/30 mm pitch. Use the actual configuration's capability in the applicable positioning assessment and verify its safety evidence. Q: What is EDM and do I need it on a press? A: External-device monitoring is a means of checking final switching elements. Whether and how it is required follows the complete safety-function design and machine rules. Do not presume it exists in a selected DQS controller. DQSRN supports manual and automatic reset per its selected-model instructions; EDM capability remains unconfirmed. Verify and validate any required final-element monitoring in the complete circuit. Q: How often should stopping time be re-measured? A: Follow the machine instructions, applicable requirements and risk assessment for routine intervals and conditions. Revalidate after relevant changes to braking, valves, tooling, loads, modes or the safety circuit. Retain dated measurements of the relevant maximum stopping performance rather than assuming one annual interval suits every application. Q: What is the difference between blanking and muting on a safety light curtain? A: Blanking changes the evaluated detection field; muting temporarily suspends a protective function under specified controlled conditions. The exact product must support the function, and its effect on access, effective detection capability, timing, faults and restart must be validated. Neither is a substitute for an appropriate safeguarding design. Q: Can I use a measuring light curtain or LiDAR to protect an operator on a press? A: Do not use ordinary measuring curtains, DD/DDOF area sensors or DLD/SDLD obstacle-detection LiDAR as personnel safeguards. A safety-rated scanner is a different device class but is not automatically appropriate for press-tool protection. Select the exact device and complete safeguarding arrangement from the machine risk assessment and applicable requirements. Q: Do you supply and support press guarding for export customers? A: Yes. DAIDISIKE manufactures at Beijiao, Shunde, Foshan and supplies safety light curtains, press guards, safety relays and door interlocks to machine builders, fabricators and distributors internationally. For press applications we normally need the machine type, the opening dimensions, the reachable body part, and — most usefully — a measured stopping time, which lets us confirm resolution and mounting distance rather than guess at them. Send those four things with an enquiry and you will get a specification back rather than a price list. # Selection guides ## How to Choose a 2D LiDAR Scanner URL: https://www.daidisensor.com/guides/how-to-choose-a-lidar-scanner/ How to choose a 2D LiDAR scanner: discrete outputs vs point-cloud data, range at low reflectivity, field of view, zone sets, and IP ratings for AGVs. Content updated: 2026-09-06 A 2D LiDAR measures distances in a scanning plane and can provide a distance profile, ordinary switching signals or both. Coverage, range and interfaces vary by model. It may simplify an area-detection task, but it does not necessarily replace several point sensors or provide personnel protection. Start by distinguishing a personnel-safety function from ordinary obstacle detection or measurement. Then decide whether the receiving system needs discrete outputs or point-cloud data. These are separate selection decisions; an Ethernet interface or a stop-labelled output does not confer a safety rating. This guide takes you through the selection in six steps, using DAIDISIKE's DLD and SDLD series as worked examples: the DLD05A3 and DLD20A5 discrete-output obstacle-avoidance scanners, the DLD30T, DLD-50D, and DLD-100D Ethernet measuring scanners, the DLD50T8 that offers both interfaces, and the SDLD-05A AGV scanner. ### What Is a 2D LiDAR Scanner and When Do You Need One? A 2D scanner samples one plane rather than the complete surrounding volume. Check the sensing technology, wavelength and laser classification on the actual model label and manual; these are not identical across every product sold as LiDAR. Consider a 2D scanner when the task needs wide-angle area coverage, multiple distance-dependent ordinary control actions, changing zones or distance-profile data. Example warning/slowdown distances are application settings, not personnel-safety limits. For a single-point task, a photoelectric or laser-distance sensor may be simpler. One caution up front: a general-purpose 2D LiDAR is not automatically a certified safety laser scanner. If your risk assessment calls for a safety-rated device, that requirement drives the selection before any performance spec — see the final section. The [LiDAR series comparison](/products/lidar/) separates safety scanners, switching detectors and measuring models. Select the function first, then compare the exact output version and the target conditions. ### Step 1: Discrete Switching Outputs or Point-Cloud Data? Decide first how the scanner will talk to your system, because it splits the market in two. Discrete-output scanners behave electrically like a photoelectric sensor. The DAIDISIKE DLD05A3 and DLD20A5 output three switching signals (NPN or PNP, rated DC30V/50 mA max) plus one status signal — no fieldbus, no protocol stack, no SDK. You configure detection zones once over USB; afterwards the scanner runs standalone and drives PLC inputs directly. This is the right choice for AGV retrofits and machine builders without a software team. Point-cloud scanners output measurement data over Ethernet for navigation, mapping, and profiling software. The DLD30T (30 m), DLD-50D (50 m), and DLD-100D (100 m) all stream data over 100BASE-TX Ethernet. Choose these when a computer or robot controller will consume the data. The DLD50T8N/P combines Ethernet data and a discrete NPN/PNP output; that output is for ordinary interlock or pre-warning use, not a certified safety OSSD. SDLD-05A combines Ethernet and digital I/O for ordinary AGV detection. Confirm the specific interface, output count and software version from the selected model rather than treating the two arrangements as identical. ### Why the Same Scanner Has Two Very Different Range Figures Nothing in a LiDAR datasheet causes more mis-specification than range, because the same unit is legitimately quoted with two numbers that differ by a factor of four or more — and they are not measuring the same thing. Returned optical energy depends on the target, angle, surface and environment. A 90% or 10% remission specification describes a defined test target; it is not a reliable conversion table for every white board, cardboard box or garment. Compare the targets and conditions attached to each range figure. A safety protective-field limit, warning-field limit and ordinary measuring range are different specifications. The exact safety scanner's manual defines the relevant test object and remission conditions. An ordinary 20 m or 30 m range does not imply any certified protective field at all. The same physics quietly reduces performance in service. A target that was white when the line was commissioned and is now grey with dust returns less light, and the usable range falls with it — one of the reasons a scanner that worked at handover can start missing objects months later without anything having been changed. ### Step 2: How Much Range Do You Really Need? Read both the high- and low-remission limits where published, then validate the actual target. DLD-50D lists 50 m at 90% and 20 m at 10%; DLD30T lists 30 m at 90% and 10 m at 10%; DLD-100D lists 100 m at 90% and 40 m at 10%. These model data are measurement limits under stated conditions, not guarantees for every dark obstacle or person. For ordinary obstacle avoidance, work backwards from the vehicle's measured behaviour and required coverage. DLD05A3 and DLD20A5 offer different ranges in a similar housing, while SDLD-05A publishes range figures at different target reflectivities. A physical drop-in fit does not establish software compatibility, sufficient response time or a personnel-safety function. Do not ignore minimum range. A scanner blind below 0.3 m can miss an obstacle a docking robot is about to touch; the DLD05A3 and DLD20A5 start detecting at 0.05 m, keeping the near-field blind zone small. Figure context: ST27 safety-scanner example only. Its documented protective field and OSSD function are separate from warning fields. The DLD/SDLD models discussed above must not inherit these safety functions from this illustration. ### Step 3: What Field of View and Blind Sector Can You Live With? Field of view determines mounting position. A 270° scanner mounted on a vehicle corner covers two full sides at once; that is the geometry of the DLD05A3, DLD20A5, DLD30T, and SDLD-05A. The DLD-50D and DLD50T8 scan 280°, and the DLD-100D family includes a 360° variant (DLD-100DC) for mast or overhead mounting where all-round coverage matters. Every non-360° scanner has a blind sector behind it — the DLD-50D, for instance, has an 80° blind sector spanning 320°–0°–40°. Point the blind sector at the vehicle body or the wall, and check that brackets, cables, and chassis edges do not intrude into the active arc. Also verify the scan plane itself: a 2D scanner sees only one horizontal slice. Obstacles below the plane (forks, pallets on the floor) or above it (overhanging racks) are invisible, so mounting height is part of the safety concept, not an afterthought. ### Step 4: What Angular Resolution and Scan Frequency Do You Need? Angular step determines geometric spacing between neighbouring samples. At 0.1 degrees and 5 m, the arc spacing is about 8.7 mm; at 0.3 degrees it is about 26.2 mm. That arithmetic is not a guaranteed minimum detectable object: beam size, target return, processing and settings also matter. Compare the exact model's resolution/frequency combinations. Scan frequency sets how often the picture refreshes: 15/30 Hz on the DLD05A3 and DLD20A5, 10–30 Hz adjustable on the DLD30T, and up to 50 Hz or 100 Hz on the DLD-50D and DLD-100D variants (the 100 Hz DLD-50DP trades down to fixed 0.32° resolution). The two trade off against each other on most platforms. Rule of thumb: prioritize resolution for detecting small or thin obstacles; prioritize frequency for fast-moving vehicles where reaction latency dominates. Check the resolution-frequency combination table for the exact model before committing. ### Step 5: How Will You Configure Zones and Switch Between Them? For obstacle avoidance, zone architecture matters more than raw specs. The DLD05A3 and DLD20A5 store 16 zone sets, each defining 3 nested detection zones mapped to the 3 switching outputs — the classic warning / slow-down / stop sequence, hard-wired. Zone sets are configured once over Micro-USB and switched in operation as vehicle conditions change: straight travel, turning, docking. SDLD-05A provides configurable zone groups and controller inputs. Check the exact software/manual revision for supported shapes, vertex counts, input selection and filtering. A hold-time or object-size filter can add latency or exclude targets; include the complete configured response in the ordinary obstacle-avoidance design rather than quoting a hardware response alone. Sketch your zone geometry per driving state before choosing hardware, then confirm the zone shapes, vertex counts, and switching inputs the scanner supports. Running out of zone sets mid-project is a painful discovery. ### Step 6: Power, Environment, and Mounting Constraints On mobile platforms, size and power budget are hard limits. The DLD05A3 measures 50 × 50 × 76 mm at 150 g on DC9–28V; the DLD-50D draws just 2.5 W from DC9–36V; the SDLD-05A weighs 374 g including cable and draws ≤2.5 W. All fit small battery-powered chassis. Match the IP rating to the environment: IP65 on the DLD05A3/DLD20A5 handles dust and light moisture; IP67 on the DLD30T, DLD-50D, DLD50T8, and DLD-100D suits harsher or outdoor-adjacent duty; the SDLD-05A is IP54, for indoor vehicles. Check ambient light immunity for sunlit sites — the DLD-50D withstands over 100,000 lux and the DLD-100D over 80,000 lux, and the DLD-100D adds multi-echo processing to help in dust, rain, and fog. Confirm the exact temperature range and laser class, including installation and service restrictions. A Class 1 label concerns accessible laser radiation during normal use; it is not a blanket exemption from the manual, damage checks or qualified maintenance, and it does not certify the machine-safety function. The [UK Health Security Agency's laser-class guidance](https://www.gov.uk/government/publications/laser-radiation-safety-advice/laser-radiation-safety-advice) distinguishes normal-use classifications. Apply it together with the scanner's own instructions, not as proof of a DAIDISIKE model's classification. ### What Degrades a LiDAR Reading in Service A scanner measures light that comes back, so anything between the unit and the target competes with the echo it is trying to time. Airborne particulate is the main one. Fog, steam, welding smoke and heavy dust scatter the outgoing pulse and return a partial echo from the air itself, which the scanner can read as a phantom object close in, or which can mask a real object further out. Rain and snow do the same intermittently, which is why an outdoor installation needs a scanner rated for it and a field configuration with tolerance for isolated returns. Direct sunlight into the receiver raises the noise floor and shortens usable range, so scanners are usually specified with an ambient light immunity figure. Mounting the unit so that the sun cannot sit in its field at any point in the day is cheaper than compensating for it later. Mutual interference matters as soon as there is more than one scanner. Two units whose fields overlap can read each other’s pulses unless the series implements interference rejection. Confirm that capability before designing a cell with several scanners rather than discovering it during commissioning. Finally the window itself. A contaminated or scratched front window attenuates both the outgoing pulse and the echo. Units intended for safety duty monitor window contamination and report it as a fault — a feature worth having, because the alternative is a scanner that degrades silently. ### Mounting Geometry Decides Whether the Scan Plane Is Useful A 2D scanner sees one plane. Everything above and below that plane is invisible to it, and this single fact causes more field problems than any electrical parameter. Mounted horizontally at ankle height on an AGV, the scan plane detects a person standing in the path but not a shelf overhanging at chest height, and not a fork protruding at knee height from a stationary pallet truck. Mounted higher it sees the obstruction and misses the feet. Neither is wrong; both need to be a deliberate decision recorded in the risk assessment rather than a consequence of where the bracket fitted. On mobile platforms the plane also moves with the vehicle. Ramps, thresholds and floor joints tilt the plane into the ground or up into free space, producing either spurious stops or a gap in coverage exactly where the vehicle is least stable. Check the extremes of the route, not the flat section. Two more geometric checks are worth running before drilling anything. Reflective floors and glossy machine panels inside the scan plane can produce mirror returns that appear as objects where none exist. And the blind sector behind the scan arc must face a wall, a structure or another guarded approach — an unguarded blind sector is simply an unguarded approach. ### Is a 2D LiDAR a Certified Safety Laser Scanner? No. A personnel-safety scanner must have appropriate device evidence and be integrated into a validated safety function. Ordinary obstacle or navigation outputs do not become safety outputs because software labels a zone 'protective' or 'stop'. DLD and SDLD models discussed here are ordinary detection or measurement equipment. The current catalogue's safety-scanner example is ST27, with its separately documented Type 3/PL d/SIL 2 design and protective-field variants. Request exact-model and version evidence; a catalogue statement alone does not validate an installation. Separate the mandatory risk-reduction function from throughput aids. A validated safeguard may protect access, while an ordinary LiDAR adds early warning or navigation data. Do not count the same unverified ordinary output as a second safety layer. Compare the [ST27 protective-field variants](/products/lidar/st27-safety-laser-scanner/) only when the application requires a safety scanner. For a mixed robot installation, the [robot sensor-role guide](/news/embodied-ai-robots-factory-sensor-role-selection/) separates floor protection, fixed openings and process measurement. Before requesting a quote, provide target size/reflectivity, required coverage, blind-sector layout, mounting height, controller interface, configured latency, environment and—where relevant—the required safety performance. The [NPN/PNP output guide](/guides/npn-vs-pnp-outputs-explained/) addresses ordinary input compatibility. Q: What is the difference between a discrete-output LiDAR and a point-cloud LiDAR? A: A discrete-output LiDAR, like the DAIDISIKE DLD05A3 or DLD20A5, converts detection into NPN/PNP switching signals that wire straight into PLC inputs — no protocol parsing needed. A point-cloud LiDAR, like the DLD30T or DLD-100D, streams distance data over Ethernet for navigation or profiling software to process. Q: Why does LiDAR range depend on target reflectivity? A: The receiver needs enough returned light, which varies with the target, angle and environment. Compare the exact product's specified remission test conditions: for example, DLD-50D lists 50 m at 90% and 20 m at 10%. A 10% target is not a guarantee for every garment or dark obstacle. Q: How many detection zones can I configure on an obstacle-avoidance LiDAR? A: The DLD05A3 and DLD20A5 store 16 zone sets of 3 nested zones each, mapped to 3 switching outputs for warning/slow-down/stop logic. The SDLD-05A stores 16 zone groups of 3 sub-zones, editable as polygons with up to 15 vertices, selected at runtime via a 4-bit input code. Q: Can one LiDAR provide both Ethernet data and a hard-wired output? A: Yes. The DLD50T8N/P outputs point-cloud data over 100BASE-TX Ethernet and simultaneously provides an NPN or PNP discrete output for interlock or pre-warning use. The SDLD-05A similarly combines Ethernet (UDP) with up to 4 NPN inputs and 4 outputs. Q: Is a 905 nm Class 1 laser safe around people? A: Class 1 concerns accessible radiation in normal use under the applicable classification. Follow the exact model label, installation instructions and service restrictions; damage or access to an internal laser requires separate consideration. Laser class does not establish a personnel-safety scanner rating. Q: Are these LiDAR scanners certified safety devices? A: DLD/SDLD detection and measuring models must not be substituted for a personnel-safety scanner. ST27 is the separately documented safety-scanner example in this catalogue. Verify the exact model, output version and certificate scope, then validate the complete safety function. Q: What should I check before mounting a 2D LiDAR on an AGV? A: Check the actual target and remission limits, field of view and occlusion, scan-plane geometry, output/data interface, configured response and filtering, supply and environment. Where personnel safety is required, verify the suitable device and complete safety architecture separately from ordinary navigation or anti-collision performance. Q: Why is the protective range of a safety scanner so much shorter than its measuring range? A: They describe different functions and test conditions. Protective-field limits belong to the exact safety scanner and its documented detection conditions; warning and measuring ranges can be larger without being safety functions. An ordinary LiDAR's headline range does not establish a smaller certified protective field. Q: Can fog, dust or rain make a LiDAR scanner unreliable? A: Yes. Airborne particulate scatters the outgoing pulse and can return an echo from the air itself, which the scanner may read as a phantom object nearby or which can mask a real object further away. Welding smoke, steam and heavy dust do the same indoors. Outdoor installations need a scanner rated for the conditions and a field configuration tolerant of isolated returns, and any unit used for safety duty should monitor its own window contamination. Q: Will two LiDAR scanners interfere with each other? A: They can, if their fields overlap and the series does not implement interference rejection. Each unit may read the other’s pulses as its own echoes. Confirm the capability before designing a cell or a fleet with several scanners — it is a specification to check at selection, not something that can be resolved by mounting alone. Q: What does a 2D scan plane not see? A: Everything above and below it. A scanner mounted at ankle height on an AGV detects a person in the path but not a shelf overhanging at chest height; mounted higher it sees the overhang and misses the feet. On mobile platforms the plane also tilts on ramps and thresholds, which can push it into the floor or up into free space. The mounting height and angle are a risk-assessment decision, not a bracket convenience. ## How to Choose an Inductive or Capacitive Proximity Sensor URL: https://www.daidisensor.com/guides/how-to-choose-a-proximity-sensor/ How to choose an inductive or capacitive proximity sensor: target material, flush vs non-flush mounting, sensing distance, wiring, and NPN/PNP outputs. Content updated: 2026-09-06 Proximity sensors detect objects without touching them, without moving parts, and without the alignment fuss of optical sensors. That makes them the workhorse position sensor of machine building: end-of-travel detection, part presence, rotation counting, level sensing. But the family splits into two technologies — inductive and capacitive — and within each, a grid of choices about mounting style, size, sensing distance, wiring, and output type. The good news is that the selection follows a fixed sequence. Decide the technology from the target material, the mounting style from the mechanical situation, the size from the required sensing distance, and the electrical interface from the control system. Each step eliminates most of the catalog. This guide walks the sequence step by step, drawing examples from DAIDISIKE's proximity range, which spans M3 to M30 threaded barrels, square housings from 8 mm up to 40 mm, 2-wire and 3-wire versions in DC and AC, and quick-disconnect connector variants. ### Step 1: Inductive or Capacitive — What Is Your Target Made Of? Inductive sensors generate a high-frequency electromagnetic field and detect the eddy currents a metal target induces. They see metal only — steel, aluminum, brass, copper — and ignore non-metal targets such as plastic guards. That selectivity reduces false detections from non-metallic dust, oil film and coolant, although metal chips close to the sensing face can still trigger an inductive sensor. Capacitive sensors detect the change in capacitance any sufficiently dense material causes. They sense metals and non-metals: plastics, wood, glass, liquids, powders, granules. DAIDISIKE's capacitive RS series (M12/M18/M30) and Q20 square series are typical — used for liquid level through a sight glass, powder presence in a hopper, or detecting plastic parts an inductive sensor cannot see. For most metal-only position and presence tasks, inductive is the usual starting point because it ignores non-metal targets; validate usable distance for the actual metal. For a non-metal target, or level detection of liquids and bulk goods, start with capacitive. If a capacitive sensor must ignore splashes or dust while detecting the real target, choose a model with an adjustable sensing distance — DAIDISIKE's metal-housing capacitive series has a potentiometer-adjustable, field-tunable trip point for exactly this. ### Step 2: Flush or Non-Flush Mounting? Flush (shielded) sensors can be screwed into a metal bracket with their face level with the surrounding metal. The surrounding metal does not trip them, the face is mechanically protected, and the design is compact. The price: the field is concentrated forward, so sensing distance is shorter. Non-flush (unshielded) sensors need a free zone around the sensing face — surrounding metal would trigger them — but reward you with substantially longer range. The difference is large, not marginal: in DAIDISIKE's DC 2-wire inductive series, sensing distance runs from 1 mm on an M8 flush model up to 25 mm on an M30 non-flush model, and the M30 non-flush versions in the standard 3-wire range reach 40 mm. Decide from the mechanics: if the sensor sits in a metal block or the face risks impact, go flush and accept the shorter range. If you can give the head clearance, non-flush buys range or lets you use a smaller barrel. Part numbers encode the choice — in DAIDISIKE's convention, non-flush models carry a T suffix (and in the AC series, P marks flush, T non-flush). ### Step 3: What Sensing Distance — and Therefore What Size? Use the selected sensor's documented assured operating distance and actual target conditions to choose the housing. Nominal values refer to a specified test target; smaller targets, non-ferrous metals, mounting metal and capacitive target properties can change the usable distance. A generic percentage of nominal range is not a substitute for those data and validation. As orientation across the DAIDISIKE inductive range: M3/M4/M5 micro barrels sense 0.6–1.5 mm — for tooling, grippers, and small mechanisms; M8 starts around 1–2 mm flush; M12 covers the 2–4 mm class; M18 flush models offer 5/8 mm (up to 8–16 mm non-flush); M30 spans 10–22 mm flush and up to 40 mm non-flush. On the capacitive side, an M8 senses 1–2 mm while adjustable M30 non-flush models reach up to 30 mm. Threaded barrels are not the only format. Square and rectangular housings mount on flat surfaces and often pack more range per installed volume: DAIDISIKE's Q08 (8 × 8 mm section, side- or top-sensing), Q10 (6–6.5 mm thin, side-sensing), Q17/Q18C (5 or 8 mm range), and Q25/Q30/Q40 blocks with 10–20 mm ranges. Thin side-sensing types like the Q08T and Q10 solve tight-clearance detection where no barrel fits. ### Step 4: 2-Wire or 3-Wire, AC or DC? 3-wire DC (10–30 V DC) is the default for anything connected to a PLC: brown (+), blue (−), black signal. The sensor's electronics are powered separately from the load, so leakage is negligible, response is fast — 0.1 ms and 1 kHz switching on DAIDISIKE's economy inductive series — and you choose NPN or PNP output to match the input card. 2-wire sensors wire in series with the load like a switch, saving one conductor and simplifying retrofits. The trade-offs are inherent to the principle: a small leakage current flows when off and a voltage drop appears when on, so verify your input's threshold tolerates them. DAIDISIKE's 2-wire DC series covers M8–M30; the 2-wire AC series (M12/M18/M30) connects directly in series with 20–250 V AC loads, switches up to 400 mA, tolerates 5 A/20 ms inrush, and specifies leakage below 1.8 mA — the practical choice when replacing limit switches in old AC control circuits. If the machine has a DC control system, prefer 3-wire DC; reserve 2-wire AC for legacy circuits you cannot rewire. Many of the inductive families publish IP67 ratings and −25 °C to +70 °C operating ranges, with built-in short-circuit and overload protection (typical trip point 180 mA on the 3-wire inductive lines); confirm the exact rating on the selected model because it is not universal across every family. ### Step 5: NPN or PNP? NO or NC? For three-wire DC outputs, PNP sources current into a sinking input and NPN sinks current from a sourcing input under conventional terminology. Use the actual controller input-module diagram, not the country where the machine was built. Select NO or NC according to the intended process logic, then assess faults separately. NC can expose some open circuits but does not provide general fail-safe behaviour. These ordinary proximity sensors must not be used as personnel-safety interlocks merely because NC is selected. DAIDISIKE part numbers encode both choices so ordering is unambiguous: in the square and barrel series, N1 = NPN NO, N2 = NPN NC, P1 = PNP NO, P2 = PNP NC (e.g., Q1705N1 is a Q17, 5 mm range, NPN, normally open); the 2-wire DC series uses D1 for NO and D2 for NC, and the AC series uses A1 for NO and A2 for NC. The [NPN/PNP and NO/NC guide](/guides/npn-vs-pnp-outputs-explained/) explains current direction and ordering checks. Return to the selected model's code table before accepting an N1/N2/P1/P2 suffix; the pattern is not universal across every family. ### Step 6: Cable or Connector, and Environmental Fit Fixed-cable sensors (typically 2 m PVC leads, longer on request) are cheapest and fine for sensors that rarely fail or move. But on machines where sensors get knocked — grippers, fixtures, weld cells — quick-disconnect connectors pay for themselves at the first replacement: swap the sensor at the connector instead of cutting, pulling, and re-terminating cable. DAIDISIKE's JM and JD series terminate in M8 or M12 connectors: the JM8 line (M8 barrel, 1–6 mm ranges) and the JM18/JM30 line with M12 4-pin connectors and up to 40 mm non-flush range. Check the environmental basics against the exact model datasheet rather than assuming: many DAIDISIKE inductive and capacitive families publish IP67 sealing and −25 °C to +70 °C operation, but some variants differ. Metal housings (nickel-plated brass or stainless steel) resist impact and chips, while PBT/PC/ABS plastic housings may suit different chemical and cost requirements. Follow the exact datasheet's side-by-side and facing clearance for mutual interference. Alternating flush and non-flush versions is not, by itself, proof that a reduced spacing is permitted. ### Quick Selection Checklist Bring the following information to the product-series decision rather than choosing a part number from diameter alone: Compare the [26 proximity sensor series and order tables](/products/proximity-sensor/) using target material, available space, flush clearance, voltage, output logic and termination. Include the mating connector and cable length in the request so a replacement is electrically and mechanically compatible. If the target is better detected optically, the [photoelectric sensing-mode comparison](/products/photoelectric-sensor/) helps decide between through-beam, reflective and background-suppression arrangements; do not force every presence task into a proximity-sensor solution. - Target material: metal → inductive; non-metal or liquid/powder level → capacitive - Mounting situation: embedded in metal → flush; clearance available → non-flush (longer range, T-suffix models) - Sensing task: actual target size/material and assured operating distance from the chosen model document; validate it in the intended mounting - Control circuit: PLC DC inputs → 3-wire 10–30 V DC; legacy AC circuit → 2-wire 20–250 V AC - Output: NPN or PNP to match the PLC input card; NO or NC to match the logic - Maintenance reality: frequent replacement or moving machinery → M8/M12 quick-disconnect (JM/JD series) - Environment: confirm the selected model's IP and temperature ratings; then pick metal vs plastic housing for the specific abuse expected Q: What is the difference between an inductive and a capacitive proximity sensor? A: An inductive sensor detects only metal, via eddy currents induced in the target. A capacitive sensor detects capacitance changes, so it also sees plastics, wood, glass, liquids, and powders. Use inductive for metal targets (more robust against contamination); use capacitive for non-metallic targets and level detection. Q: Why does a flush-mount sensor have a shorter sensing distance than a non-flush one? A: A flush (shielded) sensor concentrates its field forward so surrounding metal does not trigger it — at the cost of range. In DAIDISIKE's inductive range the spread is wide: 1 mm on an M8 flush model versus up to 40 mm on an M30 non-flush model. Q: How much margin should I leave on the rated sensing distance? A: Use the exact model's assured operating-distance specification and stated target conditions, then validate the real target and mounting. A generic 50–80% of nominal range cannot guarantee operation for all inductive and capacitive sensors, materials or target sizes. Q: When should I use a 2-wire AC proximity sensor? A: When retrofitting old AC control circuits — for example replacing a mechanical limit switch — where only two conductors exist. DAIDISIKE's 2-wire AC series wires in series with 20–250 V AC loads up to 400 mA. For PLC-based DC systems, prefer 3-wire 10–30 V DC sensors. Q: Can a capacitive sensor detect liquid level through a tank wall? A: Often yes, through a non-metallic wall of modest thickness, because the liquid behind the wall changes the sensed capacitance. Use a model with an adjustable sensing distance — such as DAIDISIKE's potentiometer-adjustable metal-housing capacitive series — to tune out the wall and detect only the liquid. Q: What do the codes N1, P1, N2, P2 mean in DAIDISIKE proximity part numbers? A: They encode output type and logic: N = NPN, P = PNP; 1 = normally open, 2 = normally closed. So Q1705N1 is a Q17 square sensor, 5 mm sensing distance, NPN output, normally open. The 2-wire DC series uses D1/D2 and the AC series A1/A2 for NO/NC. Q: Are DAIDISIKE proximity sensors sealed for washdown areas? A: An IP67 rating alone is not an approval for hot/high-pressure washdown or chemicals. Check the exact sensor and mated connector, permitted cleaning process, materials and temperature limits. Request model-specific evidence rather than assuming the same enclosure capability across the catalogue. ## How to Choose a Safety Door Switch / Interlock URL: https://www.daidisensor.com/guides/how-to-choose-a-safety-door-lock/ How to choose a safety door switch or guard-locking interlock: locking type, holding force, non-contact coded switches, ISO 14119 coding, and wiring. Content updated: 2026-09-06 A safety door switch (interlock) ties a movable guard — a door, gate, or hatch — into the machine's safety circuit. Open the guard and the hazardous motion stops; with a guard-locking version, the door additionally stays locked until the machine is safe to enter. It is the standard safeguard wherever people pass through a physical barrier occasionally rather than interacting with the machine every cycle. The selection logic runs in a fixed order: first decide whether you need plain interlocking or guard locking; then the locking principle and holding force; then contact-type versus non-contact sensing; then the coding level against defeat; and finally contacts, wiring, and mechanical accessories. This guide follows that order, using DAIDISIKE's DX family as concrete examples: the DX-D2/D3 mechanical door switches, the DX-W2/W3/W5 and DX-D6 guard-locking switches, the DX-C1 coded-magnet and DX-R1 non-contact switches, the DXL door bolt, and the DX-K key/actuator system. ### Door Switch or Door Lock: Do You Need Guard Locking? Compare the total time to reach a safe state with the time in which a person can access the hazard after the guard opens. A non-locking interlock may be appropriate only where the complete risk assessment and positioning requirements permit it. DX-D2/DX-D3 is a mechanical contact-interlock example with no guard-locking function; its contact data does not prove that every possible welded-contact fault is detected. If access could occur before the hazard ends, determine the required guard-locking function and safe release conditions. Process locking and personnel-protection locking are not interchangeable. DX-W2/W3/W5 and DX-D6 offer locking arrangements, but each exact mechanism, output and application needs verification. A third option covers full-body-access doors: the DXL safety door bolt is a purely mechanical slide bolt (48 mm bolt travel, door gaps 1–10 mm, rated 1,000,000 operations) whose base directly accepts DX-W2, DX-W3, DX-D2, or DX-D3 switches — combining a robust handle mechanism with the electrical interlock in one assembly. ### Step 1: Power-to-Release or Power-to-Lock? Guard-locking switches come in two locking principles, and the choice follows from your risk assessment, not preference. Power-to-release (mechanically locked, solenoid released — DAIDISIKE code GC, or the DX-D6 C-type): a spring holds the lock; energizing the solenoid releases it. On power failure the door stays locked. This is the usual choice when the hazard is the machine itself, because a power cut must not let anyone walk into a coasting mechanism. Plan an escape/maintenance release strategy for people who could be locked inside a cell. Power-to-lock (solenoid locked, mechanically released — code GD, or the DX-D6 D-type): the solenoid holds the lock only while energized; power failure unlocks the door. This suits processes where being locked in is the greater danger, or where the process protection (not personnel protection) is the reason for locking. The DX-W2, DX-W3, and DX-W5 are all offered in both GD and GC versions, and the DX-D6 in both C and D types, so the electrical and mechanical design carries over whichever way the risk assessment lands. ### Step 2: How Much Holding Force Does the Door Need? Holding force is what stops a person from simply pulling the locked door open. Size it against the realistic pull a person can apply to your door geometry — a large door with a long lever arm needs more margin than a small hatch. DX-W2/W3/W5 publish a 1300 N holding-force figure and DX-D6 2000 N. Verify what the manufacturer's figure represents, the exact actuator and mounting conditions, and the forces arising from the door geometry. Those numbers alone do not establish suitability for every walk-in cell door. Also check the solenoid supply: the DX-W2 solenoid runs on 24 V DC ±10% at roughly 200 mA (4.8 W); the DX-W5 additionally offers a 10–115 V AC/DC solenoid option for mixed-voltage retrofits. Mechanical life matters on high-traffic doors — the DX-W2 is rated 1,000,000 mechanical operations (150,000 electrical). ### Step 3: Contact-Type or Non-Contact Sensing? Contact-type (key-actuated) switches like the DX-D2/D3 and the DX-W lock family use a metal key on the door entering the switch head. Strengths: positive mechanical engagement, forced contact separation, and — on locking types — the holding function itself. Weaknesses: they demand door alignment within about a millimeter, wear with traffic, and collect debris in the key slot. Non-contact switches remove the mechanical key coupling. DX-C1 publishes a sensing distance up to 17 mm; this is not a guaranteed 17 mm door-offset tolerance. Obtain the exact actuator's assured switching distances and permitted alignment envelope. Its catalogue lists IP65 as standard with IP67/IP68 options, whose actual washdown conditions still require checking. The DX-R1 non-contact switch gives an assured switch-on distance of 0–10 mm and assured switch-off above 25 mm, with dual-channel solid-state outputs (150 mA) plus a 50 mA auxiliary output, a 60 ms response time, and IP65 protection. Non-contact sensing may tolerate a different alignment envelope and avoid mechanical key wear, but washdown suitability and assured switching distances remain model-specific. DX-D6 combines non-contact coded sensing with guard locking, so 'non-contact' must not be treated as meaning 'cannot lock'. ### Step 4: What Coding Level Do You Need Against Defeat (ISO 14119)? Defeat prevention is part of interlock selection and application. ISO 14119:2024 addresses interlocking-device design, selection and foreseeable defeat; coding is one measure, not a complete prevention strategy. Catalogue labels such as universal-coded S and unique-coded D describe actuator pairing. They must not automatically be translated into an ISO 14119 high coding level. Obtain the exact model's declared coding level, teach/replacement procedure and actuator compatibility; apply the prescribed installation and defeat-prevention measures. Assess why an operator might bypass the guard and provide a safe way to perform the task. DX-D6 uses its own coded key system, DX-K9S/DX-K9D, separate from the mechanical DX-K1–K8 keys. Specify the required coding and installation measures from the assessment and exact evidence, not the letters S/D alone. The [ISO 14119:2024 scope](https://www.iso.org/standard/75942.html) covers selection and defeat minimisation. The [DX-D6 configuration page](/products/safety-door-lock/dx-d6-guard-locking-safety-door-switch/) distinguishes the lock mechanism, outputs, connector and actuator; these are separate ordering decisions. ### Step 5: Contacts, Outputs, and Wiring Into the Safety Circuit For contact-type switches, pick the NC/NO complement to match your safety relay and any auxiliary signaling. The DX-D2/D3 range offers four configurations (1NC+1NO, 2NC, 2NC+1NO, 3NC); the DX-W2 offers 14 contact configurations across two independent contact compartments — 28 catalog models across the two locking types — letting one compartment monitor the door and the other monitor the lock. The DX-W5 provides six gold-plated silver-alloy contact blocks in four configurations, with contact ratings including AC-15 240 V/3 A and a DC-13 250 V/2.7 A tier. DX-R1 lists four-wire and six-wire versions with different connection arrangements. Do not assume DX-R1, DX-C1 and DX-D6 can all be placed in one interchangeable series chain. Obtain the approved circuit, maximum device count, diagnostic/fault-masking assessment, response-time calculation and compatible safety input for the exact combination. Use a suitable safety relay or controller selected for the exact input and required functions. DQSRN supports manual and automatic reset according to the selected model's instructions; EDM capability remains unconfirmed. DA31 must be checked against its own documentation. Where the application requires restart interlocking, safe release or final-element monitoring, establish how the complete circuit provides and validates those functions. Use the [safety-relay comparison](/products/safety-relay/) for documented input/contact differences, not as a blanket cascade approval. The [NPN/PNP compatibility guide](/guides/npn-vs-pnp-outputs-explained/) supports the electrical selection but does not establish a safety architecture. ### Step 6: Keys, Actuators, and Mechanical Installation Actuator selection is where door-switch projects most often stumble on site. DAIDISIKE's DX-K operation key series (11 models, DX-K1 through DX-K8 with variants) fits the DX-W2, DX-W3, DX-W5, DX-D2, and DX-D3 switch bodies, with a specified key-to-slot insertion tolerance of ±1 mm. Match the key to the door movement: sliding doors can use rigid straight keys, while hinged doors need either an angled-entry key or an adjustable one — the DX-K5 adjusts horizontally, the DX-K6 horizontally and vertically, and the DX-K8 adds a press-3 mm, rotate-90° operating head for awkward geometries. Hinged (swing) door installations require a minimum swing radius of R > 300 mm; tighter radii bind the key in the slot and wear the head. Leave preparation clearance before fitting — 1–3.5 mm for the DX-W2/W3/W5 family, 1–2.5 mm for DX-D2/D3 — and on full-body-access doors, prefer the DXL bolt assembly: the operator gets a proper handle, the switch gets a guided, repeatable key entry, and the door gap tolerance (1–10 mm) absorbs fence-panel reality. Finish the quotation against the [guard-interlock and locking-device range](/products/safety-door-lock/): door motion and lever arm, locking strategy, actuator, contact/output version, connector, mounting accessories and escape provisions. A mechanical DXL bolt is not itself an electrical safeguard. For full-body entry and several kinds of access in one cell, the [robot sensor-role application guide](/news/embodied-ai-robots-factory-sensor-role-selection/) shows why a door device cannot also prove that the entire floor space is empty. Q: What is the difference between a safety door switch and a safety door lock? A: A door switch (like the DAIDISIKE DX-D2/D3) only detects whether the guard is open and stops the machine. A door lock (like the DX-W2/W3/W5 or DX-D6) additionally holds the door locked — typically until run-down hazards such as coasting spindles have stopped or the process reaches a safe point. Q: Should I choose power-to-release or power-to-lock guard locking? A: Follow the risk assessment. Power-to-release (GC / DX-D6 C-type) keeps the door locked on power failure — usual when the machine hazard dominates. Power-to-lock (GD / DX-D6 D-type) unlocks on power failure — chosen when being trapped is the greater risk. DAIDISIKE offers both versions across the DX-W and DX-D6 ranges. Q: How much holding force do I need on a guard-locking switch? A: Use the exact lock/actuator's documented holding-force definition, mounting conditions and the forces from the real door geometry. Published 1300 N or 2000 N figures are not blanket approval for all walk-in cell doors. The guard structure, stops, fasteners and release strategy must be checked too. Q: When is a non-contact safety switch better than a mechanical one? A: Consider a non-contact device where mechanical key wear, vibration or access geometry makes it appropriate, then verify the actual alignment and environmental limits. DX-C1's published sensing distance up to 17 mm is not an offset-tolerance guarantee; request the assured switching distances and alignment envelope. For DX-R1, verify the exact electronic outputs and actuator pairing. Universal/unique catalogue labels do not by themselves establish an ISO 14119 coding level. Q: What does ISO 14119 coding mean on a safety switch? A: Coding restricts which actuator a device accepts, but universal/unique catalogue terminology is not by itself an ISO 14119 coding-level declaration. Request the exact model's declared coding level and pairing/replacement procedure, then apply the required defeat-prevention measures. Q: Can I wire several safety door switches to one safety relay? A: Only where the exact devices, wiring arrangement and controller documentation permit it. Verify permitted device count, diagnostics/fault masking, cumulative response and achieved safety performance. Do not infer universal series compatibility from a six-wire label or from membership in the DX family. Q: Are DAIDISIKE DX safety switches certified? A: Request the exact model and output/mechanism version, applicable standard edition, certificate or test scope and safety data needed by the integrator. A design-basis statement or family name is not an independent certification conclusion. Missing evidence must remain an open item. Q: What actuator key should I use on a hinged door? A: Use an adjustable key from the DX-K series — DX-K5 (horizontal adjustment), DX-K6 (horizontal and vertical), or DX-K8 (adjustable with a press-and-rotate head) — and keep the door's swing radius above 300 mm so the key enters the switch head without binding. ## How to Choose a Safety Light Curtain URL: https://www.daidisensor.com/guides/how-to-choose-a-safety-light-curtain/ Step-by-step guide to choosing a safety light curtain: resolution, protective height, range, safety distance, NPN/PNP outputs, and IP ratings explained. Content updated: 2026-09-06 A safety light curtain detects an object meeting its specified detection capability between an emitter and receiver. In a validated safety function, interruption requests the defined safe response through the safety-related control system. It can preserve access for loading and unloading, but is suitable only where hazardous motion can stop before a person reaches it; it cannot contain ejected parts or other process hazards. Start with the machine risk assessment, required safety performance and applicable machine standard. Then shortlist verified devices by detection capability, protective height, operating range, separation distance, output interface and environment. Beam pitch is a mechanical spacing, not the minimum detectable object size. This guide walks through each step. Where a concrete example helps, we reference DAIDISIKE series such as the DQC general-purpose light curtain, whose model code directly encodes beam count, pitch, and protective height. ### What Does a Safety Light Curtain Do, and When Should You Use One? A safety light curtain is an electro-sensitive protective device. Its job is to detect a person approaching a hazard early enough for the machine to stop before contact. It suits applications where operators interact with the machine every cycle — feeding a press, loading a molding machine, or passing parts into a robot cell — because there is no gate to open and close. It is not the right tool everywhere. A light curtain cannot contain ejected parts, splashing coolant, or flying sparks; if those are present you still need a physical barrier, with the curtain guarding the access opening. And if the guarded opening is a door that people walk through occasionally rather than every cycle, a safety door interlock is often simpler and cheaper. One more distinction matters at the start: safety light curtains are different from measuring light curtains and diffuse area sensors. DAIDISIKE's DD diffuse-reflection area grid, for example, is recommended by its own manual for object and area detection only — not for personnel protection. Always confirm the product family is intended for safety use before designing it into a guard. For continuous object measurement, use the separate [measuring light curtain range](/products/measuring-light-curtain/). If access is through a physical door, the [guard interlock selection guide](/guides/how-to-choose-a-safety-door-lock/) explains when monitoring or guard locking is needed. ### Step 1: What Detection Capability Does Your Hazard Require? Detection capability is the specified minimum test-object size reliably detected under the documented operating conditions. Beam pitch is the centre-to-centre spacing of optical axes. Both belong on the quotation, but they must not be substituted for one another. Select detection capability from the reachable body part, access geometry and required separation distance. A stated 14 mm detection capability is a common finger-detection specification; that does not mean a curtain with 14 mm beam pitch detects a 14 mm object. Multi-beam access barriers require their own arrangement and reach-under/over checks. The current DQC data distinguishes 10/14 mm pitch from 18/22 mm minimum detectable objects. DQT4 lists pitch choices of 7.5/15/30 mm with detection capabilities of 14/21/36 mm respectively. These examples show why the ordering pitch, rated test object and exact configuration must be checked separately; they do not establish the safety rating of a complete installation. - Required detection capability — record the rated test-object diameter, not a pitch inferred from the model code. - Protective height and beam arrangement — cover the reachable opening and check access over, under, around and behind it. - Exact model and output version — retain the relevant manual and safety-performance evidence before treating the device as a personnel safeguard. - Blanking or other configuration changes — confirm their effect on effective detection capability and re-evaluate the installation. ### Step 2: What Protective Height Covers the Opening? Protective height is the vertical span the beams actually cover. It must cover the full zone through which a person can reach the hazard — measure the opening, not the machine. On DQC-family products the arithmetic is transparent: protective height = (number of beams − 1) × beam pitch, and the model code spells it out as DQC + beam count + "/" + pitch + "-" + protective height. A DQC06/10-50 is six beams at 10 mm pitch giving a 50 mm protective height. Across the DQC range, protective heights run from 50 mm up to 3800 mm with up to 32 beams per unit. If the opening needs more beams than a standard unit provides, move up a series rather than stacking units: the DQT series extends the same through-beam concept to 72 beams (e.g., DQT72/40-2840 with a 2840 mm protective height), and economy-line options such as the JER and MK series reach protective heights up to 7960 mm at 40 mm pitch with beam counts up to 200. ### Step 3: How Far Apart Will the Emitter and Receiver Sit? Operating range is the distance between the emitter and receiver bars. Standard-range curtains cover most single-machine openings: the DQC series works from 0.3 to 3 m as standard, extendable to 0.3–6 m on request. Measure the real mounting span, then add margin for alignment tolerance and future layout changes. For wide spans — long conveyor openings, fence lines, large gantries — pick a long-range through-beam series from the start. In the DAIDISIKE catalog the DQA series is positioned exactly there: the long-range variant of the DQC, with the same eight pitch options and the same transparent model-code format, plus dedicated DQA-01/DQA-02 end-mounting brackets for long-span installation. Also decide early whether a synchronization cable between emitter and receiver is acceptable. Optically synchronized series such as the JER and DQBT need no interconnecting sync cable, which simplifies wiring when the two bars sit on opposite sides of a wide or busy opening. ### Step 4: How Close to the Hazard Can You Mount It? Separation distance depends on the applicable standard edition, approach geometry, detection capability and maximum time for the complete safety function to reach a safe state. S = K × T + an intrusion allowance is useful explanatory arithmetic, not a universal installation formula. T must account for the sensor, safety logic, final switching elements and machine stopping performance, without double counting delays already included in a measured total. Include deterioration or additional allowances as required by the applicable method; a catalogue sensor response time alone is not the machine stopping time. ISO 13855:2024 replaced the 2010 edition. The interactive example below is explicitly limited to a legacy perpendicular-approach calculation; it omits other reach, geometry and application checks. A qualified integrator must establish the current applicable method, measured stopping performance and actual detection capability before choosing a mounting position. See the [ISO 13855:2024 scope and edition information](https://www.iso.org/standard/80590.html). Give the integrator the detection capability, measured stop-time record, layout and operating modes, not just the curtain's pitch. Figure context: Conceptual relationship between the detection plane, hazard and stopping performance. The drawing does not approve a mounting distance or select the applicable standard method. ### How the Curtain Gets Into the Stop Circuit A sensor state change alone is not a safety function. The purchase specification must identify the safety-related logic and final elements that command and achieve the required safe state, including how faults and restart are managed. An OSSD-compatible safety relay or controller may evaluate the curtain, but its input mode, test-pulse tolerance and complete application must be validated. A series such as DQS can be supplied with a controller; that does not remove the need to verify the exact controller version, machine interface and safety evidence. Where required, external-device monitoring checks the final switching elements, while reset and restart interlocking address different tasks. Reset must not itself initiate hazardous motion. If a person can remain behind the detection plane, specify additional presence and restart-prevention measures; never assume clearing a beam proves the space is empty. For conventional DC input terminology, PNP sourcing outputs pair with sinking inputs, and NPN sinking outputs pair with sourcing inputs. Check the actual input circuit and common connection in the controller manual. The drawing in Step 5 is one DQC single-output variant, not a universal OSSD wiring plan. ### Step 5: Which Output Type and Power Supply Do You Need? Specify the exact output arrangement before ordering: one switched output, independent NPN and PNP outputs, and dual safety OSSD channels are different things. PNP outputs source current into a sinking input; NPN outputs sink current from a sourcing input. Match the selected controller's documented circuit, not a regional convention or a product-family label. DA31 and DQSRN are catalogue safety-relay options, not automatic compatibility approvals for every curtain. DQSRN supports manual and automatic reset according to the selected model's instructions; EDM capability remains unconfirmed. Determine where the required restart and final-element monitoring functions will be implemented; assess DA31 from its own exact circuit documentation. On power: DQC-family curtains run natively on DC12/24V. If you are retrofitting an older machine that only has AC available, an external controller option accepts AC110–220V, so you can add guarding without pulling a new low-voltage supply. Wiring is available in 4-core, 5-core, or 6-core configurations depending on series and signal options. The [output-polarity guide](/guides/npn-vs-pnp-outputs-explained/) helps specify NPN/PNP and NO/NC variants. [Rockwell Automation's input/output terminology note](https://support.rockwellautomation.com/cc/okcsFattachCustom/get/64403_7) confirms the conventional sourcing/sinking pairing; it is not a wiring approval for a DAIDISIKE safety device. Figure context: DQC 4/5-core NPN single-output wiring. Brown and blue supply both bars, the black CP line synchronises emitter to receiver, and the load sits between the positive supply and the white output wire. ### Step 6: Which Housing and Environment Rating Fit Your Machine? The DQC series publishes IP65, while DQR/DQRF variants have different enclosure specifications, including an IP68 option. An IP number alone does not approve high-pressure or hot washdown, detergents, immersion conditions or coolant compatibility. Submit the actual cleaning process and check the complete installed enclosure, connectors and cable entries. Space constraints drive a second set of choices. The DQB side-emitting series has a 15 × 30 mm cross-section with beams exiting the narrow side; the DQZ front-emitting series measures 17.2 × 30 mm; and the MK mini economy series has a 25 × 23 mm profile. These slim housings fit inside machine frames and between guides where a full-size bar will not. Where the first or last beam must sit close to a machine shoulder, check the exact end blind-zone dimension on the DQO drawing rather than reading 'zero blind zone' as literally zero. DCE offers another housing and beam-count range; its suitability for personnel protection still depends on the exact device and safety-function evidence. ### Muting and Blanking — and Why They Are Not the Same Thing Sooner or later something has to pass through the detection plane that is not a person: a pallet on a conveyor, a fixture, a workpiece taller than the opening. Two mechanisms exist for that, they are routinely confused, and confusing them is how a curtain quietly stops protecting anyone. Blanking permanently ignores specific beams so that a stationary object — a chute, a bracket, a fixture — can occupy the field continuously. Fixed blanking holds one defined zone; floating blanking lets a small object move within the field. In both cases the blanked region no longer detects anything, including a hand, so it must be physically guarded if a body part could occupy it. Muting is a controlled temporary suspension of a protective function under conditions defined by a validated safety design. Its triggering devices, sequence, timing, permitted modes and fault response must follow the exact system manual and application standard. A material-flow request alone does not make suspension safe. Do not use blanking or muting to conceal an unresolved reach path. Document why it is needed, its effect on detection and separation distance, and how access is otherwise prevented. Confirm the selected product actually supports the required function. ### Commissioning Checks Before the Machine Runs Treat these as evidence requests for qualified commissioning personnel, not instructions for an untrained buyer to test a running machine. Testing must follow an approved safe procedure, control hazardous energy and keep people out of the hazardous space. - Obtain the exact-model test-piece procedure and the record of coverage checks throughout the protective field. - Have qualified personnel validate the complete safe response under a controlled procedure; never use a hand or body as the test object. - Review the layout for access over, under, around and behind the field, with hazardous energy controlled. - Compare the measured mounting distance with the approved calculation for the actual detection capability and configuration. - Retain the maximum stopping-time measurement, test conditions, date and responsible competent person. - Verify required final-element diagnostics using the manufacturer's approved procedure; do not improvise welded-contact or wiring-fault tests. - Verify reset, restart prevention, escape and presence measures for the actual access geometry. - Check reflective surfaces, optical interference, contamination, environment and electrical installation against the exact manual. Set periodic inspection and stop-time measurement intervals from the machine instructions, risk assessment and applicable requirements. Revalidate after changes to braking, tooling, loads, operating modes or the safety circuit; there is no universal annual interval that replaces these requirements. ### What Actually Makes a Curtain Fail in Service Service problems can arise from alignment, contamination, interference or operation outside the specified conditions. The following are troubleshooting categories, not a ranked list from a published field study. Check alignment against vibration, mounting movement and the permitted operating span. Review reflective surfaces and other optical devices using the exact manual's separation and interference rules; there is no universal one-metre clearance for every curtain. Correct the cause of intermittent operation rather than widening a blanking zone. Coolant film and metal dust can attenuate the optical path. Confirm permitted cleaning methods, environmental limits and the device's fault indication; an enclosure IP rating does not establish chemical resistance or optical performance under contamination. Review fault logs and the actual operating conditions before changing configuration. Nuisance stops are a reason to investigate the installation, not to bypass a protective function. ### Which DAIDISIKE Series Should You Start With? Shortlist only devices whose exact safety evidence and detection capability meet the application requirements. Then use the following catalogue distinctions to discuss space, span and environment; the list is not approval of any family for every safeguarding task. Use the [safety light curtain series comparison](/products/safety-light-curtain/) to turn those constraints into an order shortlist. The [Type 2/Type 4 evidence checklist](/guides/type-2-vs-type-4-safety-light-curtains/) identifies the documents to request before accepting a rating. For a robot loading cell, the [sensor-role application guide](/news/embodied-ai-robots-factory-sensor-role-selection/) explains how opening, gate, floor and process sensors divide the work. [Safety edges](/products/safety-edge/) and [safety mats](/products/safety-mat/) address different contact/presence tasks where justified; none is a universal substitute for the opening safeguard. - DQC — compare the published span, height and pitch options, noting its 18/22 mm detection figures for 10/14 mm pitch and the exact single-output drawing. - DQA or DQT — investigate wider spans or higher beam counts using the exact order table and safety evidence. - DQT4 — compare the documented 14/21/36 mm detection capabilities, corresponding to 7.5/15/30 mm pitch. - DQR / DQRF — discuss wet-environment enclosure options and actual cleaning conditions; IP68 alone is not high-pressure-washdown approval. - DQB, DQZ or MK — check the available housing space without letting a narrow profile override required safety performance. - DQO — verify first/last-beam positions and the remaining end blind zone against the actual drawing. - JER economy series — confirm the exact model's detection and safety evidence before considering cost. - DA31 or DQSRN — verify input compatibility and required external functions; DQSRN supports manual/automatic reset per its selected-model instructions; EDM remains unconfirmed. Q: What beam pitch do I need for finger protection? A: Order by documented detection capability, not beam pitch. Current DQC data gives 18/22 mm minimum detectable objects for 10/14 mm pitch; DQT4 gives 14/21/36 mm detection for 7.5/15/30 mm pitch. The required test-object size, device safety evidence and installation geometry must all match the application. Q: How do I calculate the protective height I need? A: Measure the full opening through which a person can reach the hazard, then pick a beam count and pitch whose protective height covers it. On DQC-family models, protective height = (number of beams − 1) × beam pitch, and the result is written directly in the model code. Q: How far from the hazard must a safety light curtain be mounted? A: A qualified integrator must use the applicable positioning method and standard edition, actual detection capability, approach geometry and measured maximum stopping performance of the complete safety function. ISO 13855:2024 is the current international edition. The limited historical arithmetic shown here is educational, not an installation approval. Q: Should I choose NPN or PNP output for my light curtain? A: In conventional DC terminology, PNP sourcing outputs pair with sinking inputs and NPN sinking outputs pair with sourcing inputs. Check the controller's exact circuit and the selected curtain's output version. Polarity alone does not establish dual OSSD operation or safety compatibility. Q: Can I use a safety light curtain on an old machine that only has AC power? A: Yes. DQC-family curtains run on DC12/24V natively, and an external controller option accepts AC110–220V input, which makes retrofits practical on legacy machines without an available low-voltage supply. Q: What is the difference between a safety light curtain and a measuring light curtain? A: A safety light curtain is designed to protect people and drives a safety circuit. A measuring light curtain detects and dimensions objects — for counting, height checking, or vehicle separation — and must not be used as a personnel safeguard. DAIDISIKE lists these as separate categories (e.g., DQL and DQM measuring curtains). Q: Are DAIDISIKE safety light curtains certified? A: Certification and design-basis wording are different. Request the exact model and output version, relevant standard edition, actual certificate or test scope and functional-safety data. A category label or an EMC document does not establish an ESPE rating; unavailable evidence must remain an open item. Q: Does a safety light curtain have to be connected through a safety relay? A: The protective device must form part of a validated safety function whose logic and final elements achieve the required safe state and diagnostic performance. A suitable safety relay, controller or machine safety input may be used according to the exact documentation. A normal PLC status input is not a substitute, and a packaged DQS controller does not by itself validate the machine. Q: What is the difference between muting and blanking on a light curtain? A: Blanking changes which parts of the detection field are evaluated; muting temporarily suspends a protective function under defined conditions. Both require an appropriate product, validated control strategy and assessment of access, timing, faults and effective detection capability. Do not assume a fixed sensor count or a generic sequence applies to every installation. Q: Why does my light curtain trip intermittently when nothing is in the way? A: Possible causes include alignment drift, vibration, thermal movement, lens contamination and optical interference. Nearby reflective surfaces can also create a dangerous detection bypass rather than simply a nuisance trip. Follow the exact manual's mounting, reflection-clearance and interference-prevention requirements; do not assume every series supports coding or interference-free operation. Diagnose and correct the cause instead of widening a blanking zone. Q: How often should the safety distance be re-checked? A: Use the machine instructions, risk assessment and applicable requirements to set inspection and measurement intervals. Revalidate after relevant changes to braking, loads, tooling, modes or the safety circuit. Keep the measured maximum stopping-time record; an assumed universal annual interval is not a substitute. ## NPN vs PNP Sensor Outputs Explained URL: https://www.daidisensor.com/guides/npn-vs-pnp-outputs-explained/ NPN vs PNP sensor outputs explained: sinking vs sourcing, PLC input matching, NO vs NC logic, wiring colors, and how to pick the right output type. Content updated: 2026-09-06 Many three-wire DC proximity and photoelectric sensors are ordered in NPN or PNP versions. Selecting a version incompatible with the controller can leave the input unresponsive even though the sensor is powered. Light curtains, area sensors and LiDAR can use different conductor assignments and output architectures, so the simple three-wire example must not be applied to them without the exact diagram. The distinction is simply which way current flows through the load. An NPN output sinks current: it connects the signal line to 0 V. A PNP output sources current: it connects the signal line to +V. Neither is better; the only question is which one your controller's input expects. This guide explains both circuits, shows how to identify what your PLC needs, covers the separate NO/NC decision, and lists how output types are coded across DAIDISIKE product families so you can order the right variant first time. ### What Do NPN and PNP Actually Mean? The names describe the transistor output arrangement. In a common three-wire DC sensor example, brown supplies +V, blue is 0 V and black is the switched output. These are example conventions, not a universal wiring assignment: check the exact voltage, connector pins and conductor functions before connecting a real device. In an NPN sensor the transistor connects the output toward the 0 V rail when active. Current flows from the load into the sensor, which is why it is called a sinking output. Whether target detection makes the output active is the separate NO/NC or light-on/dark-on decision. In a PNP sensor the active output supplies current from +V through the load toward 0 V, hence sourcing output. NPN/PNP describes current direction; response, leakage, residual voltage and switching capacity still need comparison between the exact variants. ### How Does an NPN (Sinking) Output Circuit Work? Wire the load — a PLC input, relay coil, or indicator — between the +V rail and the sensor's black wire. When the sensor switches, it completes the path to 0 V and current flows: +V → load → black wire → sensor → 0 V. Because the output pulls to 0 V, the PLC input on the other side must be the type that expects to see current flowing out of it into the sensor. In PLC terminology that is a sourcing input: its common terminal is wired to +24 V, and each input channel sources current to whatever pulls it low. NPN sensors and sourcing inputs are two halves of the same circuit. One practical caution: with the sensor off, the black wire floats near +V through the load. During troubleshooting, measure voltage between black and 0 V — near +V means off, near 0 V means on — rather than trusting a test lamp connected the wrong way. ### How Does a PNP (Sourcing) Output Circuit Work? In this conventional three-wire example, wire the load between the sensor's black wire and 0 V. When the output is active, the sensor connects black to +V and current flows: sensor → black wire → load → 0 V. Whether detection activates or deactivates the output depends on the NO/NC version. The matching PLC side is a sinking input: its common terminal is wired to 0 V, and each channel accepts (sinks) the current the sensor pushes in. PNP sensors and sinking inputs pair together. Do not select polarity as a shortcut to personnel safety. A short circuit can create different input states depending on which conductor and supply rail are involved. An ordinary PNP or NPN input needs the appropriate diagnostics and system architecture before it can form part of a safety function. ### Which One Does Your PLC Input Need? Open the exact input-module manual. Under conventional terminology, a sinking DC input accepts current from a PNP sourcing sensor, while a sourcing input supplies current to an NPN sinking sensor. For a configurable module, the permitted common-terminal wiring and channel grouping must follow its documentation. A regional preference or a controller brand is not an input specification. Record the complete input-module number, common-terminal arrangement, supply, input thresholds and permitted leakage current. Mixed fleets can require different output versions even when the PLCs carry the same brand. For an ordinary control input, an approved interface relay or converter may resolve a polarity mismatch, but it adds delay, load requirements and failure modes. Do not insert such a converter into a personnel-safety circuit without evaluating and validating that complete safety function. The conventional pairing is documented in [Rockwell Automation's sourcing/sinking note](https://support.rockwellautomation.com/cc/okcsFattachCustom/get/64403_7). Use it to understand current direction, then return to the actual input-module and sensor diagrams. ### NO vs NC: The Second, Independent Choice Output polarity says which rail the signal switches to; normally-open versus normally-closed says when. A normally-open (NO) output turns on when a target is detected — the natural choice for presence detection and counting. A normally-closed (NC) output is on when no target is present and turns off on detection. An NC output can make some open-circuit faults visible in ordinary process logic, but it does not diagnose every fault: a short to the active rail can conceal a detection. Guard monitoring and other personnel-safety functions require appropriately rated devices and a validated circuit, not merely an NC proximity switch. The two choices multiply into four standard variants — NPN NO, NPN NC, PNP NO, PNP NC — and DAIDISIKE part numbers encode them directly: N1, N2, P1, P2 respectively in the proximity and square-sensor series. A Q1705N1 is NPN normally-open; a Q1705P2 would be PNP normally-closed. Some products offer both contacts at once: the M12 capacitive connector series includes a 4-wire NO+NC version. Use the [proximity sensor selection guide](/guides/how-to-choose-a-proximity-sensor/) to choose target, mounting and connector first. The [proximity series tables](/products/proximity-sensor/) then provide the relevant ordering codes; code meanings are not automatically transferable to other product families. ### How Do You Wire a 3-Wire DC Sensor Correctly? A common three-wire DC convention is brown (+V), blue (0 V) and black (output); white on a four-wire unit may have a different assigned function. DAIDISIKE light curtains and area sensors include diagrams that differ from this convention. Read the actual terminal or wire-function table, not the colour alone. Before specifying a load, check the exact output current, residual voltage, off-state leakage, supply and permitted capacitive or inductive load. The DLD05A3/DLD20A5 switching-output specification is not a limit for the whole sensor catalogue. Any interface device and suppression arrangement must follow the device and controller instructions. Current DD/DDOF documentation assigns independent outputs: black is NPN and white is PNP. Connect the required output and insulate the unused output separately; do not join it to a supply rail or to the other output. The current version is NO by default, with NC set by its documented power-on button procedure. The earlier wire-strapping instruction is not applicable to this version. Check the current [DD/DDOF output and version details](/products/safety-light-curtain/dd-diffuse-reflection-area-light-curtain/) before ordering or replacing an older unit. Both are ordinary area/object-detection sensors, not personnel safeguards. ### Which DAIDISIKE Products Offer Both NPN and PNP? Availability is model- and version-specific. Use this list to find the relevant order table, then verify output count, polarity, logic and connector assignment instead of assuming every variant is interchangeable: For an optical part-presence task, compare the [photoelectric sensor modes and output options](/products/photoelectric-sensor/); for area measurement or discrete LiDAR signals, compare the [LiDAR interfaces](/products/lidar/). This article is a cross-category electrical aid, not a single-product buying guide. - Proximity sensors — inductive (M3–M30 barrels, Q-series squares) and capacitive series are ordered NPN or PNP via the N/P code, each in NO (1) or NC (2) logic - Light curtains — DQC, DQE, DQB, DQZ, DQBT, DCE, JER and MK list electrical variants; a selectable NPN/PNP signal is not proof of dual safety OSSD channels or a Type rating - 2D LiDAR — DLD05A3-3N / -3P and DLD20A5-5N / -5P provide three switching outputs plus one status output in NPN or PNP versions - Measuring LiDAR with discrete output — DLD50T8N (NPN, 50 Hz) and DLD50T8P (PNP, 100 Hz) - Non-contact door switches — check the exact DX-R1 polarity, pin assignment and documented cascade arrangement; ordinary polarity matching alone does not validate a safety input - DD/DDOF area sensors — current documentation provides separate black NPN and white PNP outputs; select one by the approved diagram, not by shorting wires Q: What is the difference between NPN and PNP sensor outputs? A: An active NPN output sinks current toward 0 V; an active PNP output sources current from the positive supply. Match that current path to the input-module circuit. NO/NC logic and the electrical performance of the exact output version are separate specifications. Q: Is NPN or PNP better? A: Neither is universally better. Use the controller's documented input circuit and compare the exact variants' electrical limits. Do not infer a safety rating, reliable broken-wire detection or a speed advantage from the letters NPN or PNP alone. Q: How do I know whether my PLC needs NPN or PNP sensors? A: Read the exact input-module circuit. Conventionally, a sinking input pairs with a PNP sourcing sensor, while a sourcing input pairs with an NPN sinking sensor. Configurable modules must be wired by their approved common-terminal and channel-group instructions. Q: Can I connect an NPN sensor to a PLC that expects PNP? A: Not as a direct substitute unless the input circuit supports it. A suitable interface can be considered for ordinary controls after checking electrical limits and delay. Any change to a personnel-safety circuit requires evaluation and validation of the whole function. Q: What do NO and NC mean, and how do they relate to NPN/PNP? A: For the conventional target-sensing example, NO (normally open) activates on detection and NC (normally closed) deactivates on detection. NO/NC is independent of NPN/PNP. Some DAIDISIKE proximity and square-sensor families use N1 (NPN NO), N2 (NPN NC), P1 (PNP NO) and P2 (PNP NC); this is not a universal code for every product. Verify the exact series ordering table. Q: What are the standard wire colors on a 3-wire DC sensor? A: Brown positive, blue 0 V and black output is a common three-wire example, not a rule for every sensor. Verify the exact manual. Current DD/DDOF uses separate black NPN and white PNP outputs, while some light-curtain diagrams assign the conductors differently; do not short unused outputs. Q: Do 2-wire sensors have an NPN/PNP polarity? A: No — a 2-wire sensor wires in series with the load like a switch, so the sinking/sourcing question largely disappears. That simplicity costs a small off-state leakage current and an on-state voltage drop, which your input must tolerate. DAIDISIKE offers 2-wire DC (10–30 V) and 2-wire AC (20–250 V) proximity series. Q: Which light curtain output should I order for a Siemens PLC? A: Check the exact Siemens input-module number and wiring diagram; the brand alone does not establish its input circuit. A sinking DC input conventionally requires a PNP sourcing output. For a light curtain, also verify the actual output version, safety-input compatibility and complete safety function. ## Type 2 vs Type 4 Safety Light Curtains URL: https://www.daidisensor.com/guides/type-2-vs-type-4-safety-light-curtains/ Compare Type 2 and Type 4 light-curtain claims before ordering: fault behaviour, exact output version, detection capability, certificate scope and required evidence. Content updated: 2026-09-06 Two light curtains can share a housing, pitch, height and range while differing in safety-related fault behaviour. IEC 61496 Type and the exact model documentation help distinguish those claims; the product photograph cannot. Type 2 and Type 4 address different safety-related requirements. Type 2 relies on periodic testing; Type 4 has more demanding fault-response requirements. Output count alone does not prove the Type, and a component classification does not establish the achieved performance of the complete machine safety function. This page focuses on the buyer's evidence check: which model and output version is quoted, what the actual certificate or test document covers, and what remains for the integrator to validate. It is not a substitute for the applicable standards or the machine risk assessment. ### Where "Type" Comes From: IEC 61496 in Plain Terms IEC 61496-1 provides general design and test requirements for electro-sensitive protective equipment; IEC 61496-2 adds requirements for active opto-electronic protective devices such as light curtains. Type is not a measurement-resolution or housing-quality grade. Record the precise standard edition, device Type, configuration and test or certificate scope. A claim about a design basis, an EMC report and an ESPE type-examination document answer different questions and must not be presented as interchangeable. The published scopes of [IEC 61496-1:2020](https://webstore.iec.ch/en/publication/63115) and [IEC 61496-2:2020](https://webstore.iec.ch/en/publication/63117) identify the general and optical-device requirements respectively. ### The Real Difference: What Happens When a Fault Occurs For a Type 4 claim, request the documented fault behaviour and safety-output arrangement, including how the receiving safety logic evaluates the outputs. Dual monitored OSSD channels are a common implementation, but a drawing showing two wires or a marketing phrase does not establish conformity. For a Type 2 claim, request the required test method, timing, test input and response to a failed test. The integrator must assess those conditions against the safety function. Do not convert a conceptual timeline into a universal test interval or an immediate-response guarantee. Figure context: A purchasing comparison of required evidence, not an approval for a named machine or series. ### Type and Performance Level: Check Both, Not One Instead of the Other Type 2 devices are commonly specified for applications up to PL c and Type 4 devices up to PL e, where the exact device documentation supports those claims. The machine's required Performance Level, PLr, is determined by the risk assessment and applicable machine requirements. The achieved PL of the complete safety function also depends on the input, logic, final elements, diagnostics, reliability data and validation. Do not equate Type 4 with an automatically achieved Category 4/PL e installation, or accept a Type 2 product for a PL d/e requirement merely because its range or price is attractive. ### Resolution Has Nothing to Do With Type Detection capability and Type answer different questions. Detection capability is the rated test-object size under specified conditions; Type concerns safety-related device requirements. Neither can be inferred from the other. Beam pitch is separate again: current DQT4 data gives 14/21/36 mm detection capability for 7.5/15/30 mm pitch, while current DQC data gives 18/22 mm objects for 10/14 mm pitch. These figures illustrate a terminology distinction, not approval of an output version or machine application. Use the [light-curtain selection guide](/guides/how-to-choose-a-safety-light-curtain/) for opening, span and detection decisions, then return to the exact evidence checklist here before releasing a purchase order. ### When a Type 2 Light Curtain Is Enough A Type 2 device can be considered only when the required safety performance, applicable machine standard and documented test arrangements permit it. An occasional-access opening or a slow machine does not by itself establish that result. Keep the risk assessment, safety-requirements specification and exact device evidence in the machine file. If the required performance or test strategy remains unresolved, the purchase specification remains unresolved too; budget is not a substitute. Figure context: A buffer zone, press opening or robot cell still needs its own assessment. The illustration does not assign a Type from the location alone. ### When the Requirement Excludes a Type 2 Device If the safety function requires PL d or PL e, a Type 2/PL c device cannot satisfy that input-device requirement. A higher-capability device and appropriate complete architecture must be selected and validated; the machine-specific rules may add further requirements. Presses, press brakes and shears require particular care with stopping performance, operating modes, tooling and access geometry. A fixed light curtain, ram-associated laser guard or other measure may be appropriate only within the applicable application and machine requirements. The [press and press-brake protection comparison](/products/press-brake-protection/) separates available product arrangements. The [press purchasing and verification article](/news/press-brake-punch-press-light-curtain-guarding/) identifies the machine information needed before a system can be specified. ### Why the Exact Output Version Matters More Than a Family Label Do not assign one blanket Type 4/dual-OSSD statement to DCE, DQA, DQC, DQE, DQO, DQR, DQZ and DQSA. A family can have different electrical versions, and the current DQC material includes a single-output drawing. An NPN/PNP option is not evidence that a device supplies two safety OSSD channels. Before ordering, obtain a row for the exact model: output count and function, Type/design basis, actual certificate scope, detection capability, maximum response time, controller input requirements and missing evidence. DQC's available EMC material must not be represented as an ESPE certificate. Economy or unpublished variants require the same evidence discipline. Start from the [current safety light curtain series list](/products/safety-light-curtain/) and compare only configurations supported by their own documents. Where a requirement cannot be evidenced, request clarification rather than filling the gap with another series' rating. ### How to Verify a Claimed Type Rating A product listing is the beginning of verification, not its conclusion. Ask for a quotation and evidence pack that can be reconciled line by line with the order code. DA31 and DQSRN must be assessed by their exact controller documentation. DQSRN supports manual and automatic reset per its selected-model instructions; EDM capability remains unconfirmed. Validate all required functions in the complete architecture. The [safety-relay comparison](/products/safety-relay/) is a starting point, not automatic compatibility approval. For deeper electrical interpretation, the [DAIDISIKE engineering reference on fsddsk.com](https://www.fsddsk.com/ossd-wiring-npn-pnp-with-edm-dual-channel-loops-edm-feedback-common-wiring-mistakes) covers OSSD terminology and integration. Qualified personnel must still follow the exact product and machine instructions. Send your required performance, access layout, detection requirement, selected controller and destination market through the [inquiry form](/contact/). Request a configuration-specific document list before treating any model as approved. - Exact sensor, transmitter/receiver and controller identifiers, hardware/output version and document revision. - Applicable IEC 61496 part and edition; distinguish design-basis wording from a model-specific certificate or test scope. - Rated detection capability separately from beam pitch, and the maximum response time for the selected configuration. - Safety data needed by the integrator, such as PFHd and mission time where applicable; mark unavailable items explicitly. - Compatible safety-input arrangement, required reset/restart and final-element monitoring functions, and who implements each function. - Accessories, cable/connector assignment and delivery documents matched to the same configuration; price alone is not proof for or against a rating. Figure context: Required performance and device evidence guide the shortlist. The complete safety function still needs application-level validation. Q: Is a Type 4 light curtain always safer than a Type 2? A: Type 4 has more demanding device fault-response requirements, but neither Type number approves a complete installation. Selection still depends on the required safety performance, machine-specific rules, device documentation and validation of the whole safety function. Q: Can I tell Type 2 from Type 4 by looking at the datasheet resolution? A: No. Detection capability, beam pitch and Type are separate specifications. Verify the rated test-object size and actual Type evidence for the exact model; two output wires or a fine pitch alone do not prove a rating. Q: Does Type 4 require a specific safety relay? A: Select a receiving safety relay, controller or machine safety input compatible with the exact safety outputs and required functions. DA31 and DQSRN are not automatic approvals for every curtain. DQSRN supports manual and automatic reset per its selected-model instructions; EDM capability remains unconfirmed. Validate all required functions in the complete circuit. Q: Which DAIDISIKE series should I start with for a Type 4 application? A: Begin with the required Type/PLr and exact device evidence, not a default series recommendation. DQT4 publishes 14/21/36 mm detection capabilities for 7.5/15/30 mm pitch; verify its selected output and certificate scope. Do not assume DQC or another family is Type 4 because a category page groups it with other light curtains. Q: Are there Type 1 or Type 3 light curtains? A: The light-curtain standard and safety-scanner standard cover different sensing technologies. Type 2 and Type 4 are common light-curtain classifications; ST27 is listed separately as a Type 3 safety laser scanner. Verify the exact applicable standard part and document scope rather than treating a laser guard, scanner and light curtain as interchangeable.