DQT4 Type-4 Safety Light Curtain

Technical Specifications

Overview

DQT4 is a series of opto-electronic safety light curtains, named per the catalogue as the "4级安全光幕" ("Level 4") series in our range. The catalogue documents it as designed to the Type 4 architecture of EN/IEC 61496-1/-2 and GB/T 19436-1/-2, and to PLe / Category 4 of ISO 13849-1 (SIL3 per the same reference). It uses a 9-pin wiring interface and is available in three beam-pitch grades — 7.5 mm, 15 mm, and 30 mm — with a corresponding detection accuracy (minimum detectable object, per the catalogue's own parameter table) of 14 mm, 21 mm, and 36 mm respectively, described in the catalogue as finger, hand, and arm/body protection. It is intended for machine builders, panel integrators, and end users who need to guard press brakes, punch/stamping presses, and automated cells with a light curtain rather than mechanical guarding. Certification documents are available on request.

The series offers the finest beam pitch and the widest beam-count/height range in our light-curtain lineup: a 7.5 mm pitch (14 mm detection accuracy) at the fine end, and configurable protective heights from 90 mm up to 5970 mm at the large end. The 7.5 mm grade spans 15 to 319 beams (step 8), the 15 mm grade spans 8 to 200 beams (step 4), and the 30 mm grade offers a standalone 4-beam model plus 8 to 200 beams (step 4), letting a single series cover point-of-operation guarding from precision stamping to large machine perimeter access. Up to three DQT4 units can be cascaded, and each unit provides dual independent, self-diagnosing OSSD outputs.

Features & Benefits

Applications

Models & Ordering Information

138 standard models across 3 beam-pitch options. Select the pitch your risk assessment calls for, then the protective height that covers the opening.

How to Select

1. Choose 7.5 mm (finger detection) for hazards where a finger or small body part could enter the danger zone; it supports the closest safety-distance mounting of the three grades and is available in beam counts 15 to 319 (step 8).
2. Choose 15 mm (hand detection) for hazards where hand/palm-level intrusion is the relevant risk; available beam counts are 8 to 200 (step 4).
3. Choose 30 mm (arm detection) for larger openings where arm-level intrusion is the relevant risk and maximum protective height is needed; available as a single 4-beam/90 mm model or 8 to 200 beams (step 4).
4. Match the protective height to the physical height of the opening to be guarded; beam count and height are fixed together per resolution grade in the model list, so the model number is selected as a pair.
5. All DQT4 models use a 9-pin wiring interface; output-signal details should be confirmed with the factory before final specification.
6. Select mounting accessories: the DQT4-09 end-mounting kit ships as standard, with DQCA-01/02/03/05 general-purpose brackets compatible where an alternative mounting geometry is needed.
7. Pair DQT4 with our DQSRN safety relay or DA31 emergency-stop relay if a complete safety control circuit is required; final circuit design should follow the relay manufacturer's wiring instructions and the machine's risk assessment.

📘 Need the full method? How to Choose a Safety Light Curtain · Type 2 vs Type 4 Safety Light Curtains

When NOT to specify the DQT4 — and what to use instead

Specifications we do not publish yet

We only publish a figure once we are confident it is true. The items below are still being validated through further testing and real-world customer feedback, so for now we would rather leave them open than guess. If one of them matters to your design, ask us for the latest validated status.

• PFHd and DCavg figures for a full ISO 13849-1 / IEC 61508 machine-safety calculation. The catalogue states PLe / Category 4 / SIL3 and an MTTFd of 99 years, but does not publish PFHd or DCavg.
• TUV and UL certificate numbers and their exact scope (which DQT4 models/configurations are covered). Certification documents are available on request.
• ISO 13855 safety-distance calculation guidance and the exact response time per beam count — the catalogue gives only the <= 20 ms overall maximum.
• Relay (volt-free) output availability — the parameter table documents NPN/PNP transistor output only; whether a relay-output variant exists for DQT4 (as the "J" code does for other series in the catalogue) needs confirming.
• Whether the 0.3-6 m sensing-distance option (model-code letter C) is actually orderable for every beam-count/pitch combination, since the full model list in the catalogue prints only "0.3-3 m" for every row shown.
• The difference between the DQCA and DQCA2 controllers, and which DQT4 configurations require an external controller versus operating stand-alone.
• Cable length options and the full 9-pin aviation-connector pinout, beyond the two wiring examples documented (PNP dual-output, NPN dual-output).
• The special-mark suffix "M" ("advanced function") is named in the model-code diagram but not defined elsewhere in the catalogue; its actual function needs confirming

Works Well Together

On the same machine or line, DQT4 is typically ordered together with: Safety Relays · Safety Door Locks & Switches · Press & Press Brake Protection

DA31 Emergency-Stop Safety Relay Module

Ultra-slim 22.6 mm Category 4/PL e/SIL 3 safety relay with dual-channel PNP/NPN input and a solid-state status output.

DX-C1 Magnetic Coded Safety Switch

Non-contact coded-magnet safety switch with 17 mm sensing range and high misalignment tolerance for guard doors.

DKE-L3 Press Brake Laser Protection

Ram-mounted laser guarding that tracks the punch tip on press brakes and shears without blocking hand-fed work.

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