D3J0312 Modbus
12 isolated inputs + 8 relay/transistor outputs on Modbus-RTU/RS-485 - the D3J03 series' highest I/O count.
🔍 Click to enlarge · 1/3Technical Specifications
| Type | ASIC-based Modbus-RTU/RS-485 digital input/output module, 12 inputs + 8 outputs |
|---|---|
| Default order code | D3J0312M111 (all-relay output, pulse unavailable, no wireless) |
| Product ID / default slave address code | 0x3312 |
| Input | 12 fully isolated digital inputs, plus 2 analog input channels and a 5V/100mA sensor supply |
| Output channels | 8 fully isolated digital outputs (relay type or transistor type, selectable), plus up to 2 pulse PWM/PTO outputs |
| Communication interface | RS-485 (Modbus-RTU); USB port included; optional 2.4GHz wireless MODBUS-OTA |
| Default baud rate | 9600bps |
| Default data format | 8 data bits, even parity, 1 stop bit |
| Default slave address | 0x02 |
| Selectable baud rates | 300 / 600 / 1200 / 1800 / 2400 / 4800 / 7200 / 9600 / 14400 / 19200 / 28800 / 38400 / 56000 / 57600 / 76800 / 115200 |
| Selectable parity | None / odd / even (default even) |
| Selectable stop bits | 1 (default) / 1.5 / 2 |
| Slave address range | 1-247 (0x01-0xF7) |
| USB mode address | Fixed at 0x01 when USB is connected; RS-485 then switches to master mode |
| Input trip threshold | Approximately 3V (above = high level, below = low level) |
| Input counting | Each channel has a DINnCNT edge counter that increments on a rising edge, rolls over at 65535, and can be cleared by writing a value |
| Input filtering | Each channel has an independently adjustable DINnFLT anti-bounce filter (0 = off); saved values persist through power loss |
| Supported function codes | 0x02 read discrete inputs; 0x03/0x06/0x10 read/write holding registers (e.g. DOUTnDV); 0x04 read input registers; 0x16 mask write; 0x17 read/write multiple registers; 0x11 report device ID |
| Register protection | Sensitive registers (name, serial port, wireless, etc.) require writing ASCII "UL" to the safety-lock register to unlock before changes; the register re-locks automatically after each write |
| Supply voltage | DC 11-28V |
| Supply ripple | < 1Vp-p |
| Supply current | < 1500mA |
| Communication terminal stress (normal) | DC 0-5V |
| Input terminal stress (normal) | DC 0-30V |
| Output stress, relay type (normal) | DC 30V or AC 0-220V, 8A |
| Output stress, standard transistor type (normal) | DC 12-48V, 8A |
| Output stress, high-speed transistor type (normal) | DC 12-24V, 8A |
| Communication isolation voltage (normal) | < 250V |
| Input isolation voltage (normal) | < 250V |
| Output isolation voltage, relay type (normal) | < 250V |
| Output isolation voltage, transistor type (normal) | < 130V |
| Operating temperature | -20 to 60 degrees C |
| Supply voltage (absolute maximum) | DC 28V |
| Fuse (one-time) | DC 250V, 3000mA, slow-blow |
| Communication terminal stress (absolute maximum) | DC 50V |
| Input terminal stress (absolute maximum) | DC 50V |
| Output stress, relay type (absolute maximum) | DC 30V or AC 0-220V, 8A |
| Output stress, standard transistor type (absolute maximum) | DC 55V, 10A |
| Output stress, high-speed transistor type (absolute maximum) | DC 40V, 10A |
| Communication/input isolation voltage (absolute maximum) | DC 1000V, 60s (type test) |
| Output isolation voltage, relay type (absolute maximum) | DC 1000V, 60s (type test) |
| Output isolation voltage, transistor type (absolute maximum) | DC 250V, 60s (type test) |
| Relay mechanical life | > 100,000 operations (> 10,000 under heavy load) |
| Storage temperature | -40 to 85 degrees C |
| ESD immunity | IEC 61000-4-2: 4kV discharge on all terminals - normal operation (A) |
| EFT immunity | IEC 61000-4-4: 2kV/5kHz/2min - normal operation (A); 4kV/5kHz/2min - no permanent damage (C) |
| Surge immunity | IEC 61000-4-5: 1kV to ground on all terminals - no permanent damage (C) |
| Creepage distance | > 6.5mm measured (requirement > 6mm), pollution degree 3, material group IIIa/IIIb |
| Electrical clearance | > 2.2mm measured (requirement > 2mm) |
| I/O response time | Typical 20ms |
| Serial command reply time | Maximum 25ms |
| Module dimensions | 158 x 88 x 59mm (tolerance +/-5%) |
| Terminal pitch | 5.08mm |
| Terminals | 44 screw terminals, 12 input indicator LEDs, 1 power indicator LED, 1 USB port, 2 analog input channels (internal, brought out by lead wire) |
Overview
The D3J0312 is a 12-input, 8-output Modbus-RTU/RS-485 digital input/output module built around an ASIC core, for engineers who need to concentrate a large panel's switches, limit switches, alarms and interlocks onto one board instead of stacking multiple single-function I/O modules or a small PLC. It combines 12 fully isolated digital inputs with 8 fully isolated digital outputs (relay type or open-drain transistor type, selectable at order time) and is the highest channel-count model in the D3J03 input/output series.
Each of the 12 inputs carries its own edge counter (rolling over at 65535) and an adjustable digital filter that can be saved through power loss, while each of the 8 outputs supports direct on/off drive, 5 jog/delay timing modes, input-linked local control (output n follows input n) and an emergency-brake function (BRKFLG) that forces outputs to a preset safe state without host intervention. The module runs on DC 11-28V, communicates by default at 9600bps/8-even-1 with a slave address range of 1-247, and adds 2 analog input channels, up to 2 high-speed PWM/PTO pulse outputs and a 5V/100mA sensor supply, plus a USB port and an optional 2.4GHz wireless MODBUS-OTA link.
Features & Benefits
12 In + 8 Out On One Board - Half the Panel Hardware of a Stacked I/O Rack
A single 158 x 88 x 59mm module carries 12 fully isolated digital inputs and 8 fully isolated digital outputs - the highest channel count in the D3J03 series. One RS-485 drop, one DC 11-28V feed and 44 screw terminals replace the base unit, expansion cards, backplane and inter-module wiring you would need to reach the same 20 points with a small PLC, and it drives the per-point cost down to the lowest in the series.
The Machine Still Stops Safely When the Bus Goes Down
Input linkage ties each output to its matching input (output n follows input n) and the BRKFLG emergency brake forces outputs to a preset safe state the moment a limit or e-stop input trips - at the highest priority, ahead of any host coil forcing. Both run inside the module with a typical 20ms I/O response, so a cut RS-485 pair, a hung SCADA or a rebooting PLC does not leave 8 loads energised.
Relay or Transistor Output - Pick the One That Matches Your Load
Relay-type channels switch DC 30V or AC 0-220V at 8A with contact isolation, ideal for 220V contactors, fans and lamps. Transistor-type channels are open-drain, rated DC 12-48V at 8A, and carry a built-in 10A freewheeling diode - so a solenoid or DC motor connects directly with no external suppression diode to spec, source and wire. You choose per order code ([ddd] 1st digit: 1=relay, 2=transistor) instead of buying two different products.
Edge Counters and Bounce Filters Take the Grunt Work Off the Host
Every one of the 12 inputs has its own DINnCNT counter that increments on each rising edge and rolls over at 65535, plus an independently adjustable DINnFLT anti-bounce filter that survives power loss. Relay contacts, flow meters and pulse encoders can be counted and de-bounced in the module, so the master reads a clean total over Modbus instead of polling fast enough to catch every edge itself.
Local Timing Without a Line of PLC Code
Each of the 8 outputs supports 5 jog/delay modes: once the trigger condition is met the channel closes and drops out after a configurable delay, with the time unit and value set by register. That covers pump run-on, valve pulse dosing and fan post-purge sequences on the module itself - no ladder logic, no scan-time budget, and the sequence keeps running if the host is offline.
Analog Input, Pulse Output and 5V Sensor Power - Included, Not Extra
Alongside the 12 DI and 8 DO, every unit ships with 2 wide-range analog input channels, up to 2 high-speed pulse outputs for PWM speed control or PTO stepper drive, and a 5V/100mA sensor supply. A soil-moisture or temperature probe can be powered, read and acted on from the same board that switches the pump - removing a separate analog module and its power supply from the panel.
Speaks Modbus Straight Out of the Box, Three Ways
Modbus-RTU over RS-485 at a default 9600bps / 8-even-1 with slave addresses 1-247 and baud rates from 300 to 115200 lets a PLC, HMI or SCADA poll it with no driver. Function codes 0x02, 0x03, 0x04, 0x06, 0x10, 0x16, 0x17 and 0x11 are supported. The included USB port doubles as a USB-to-serial adapter and puts the RS-485 side into master mode (address 0x01), and MODBUS-ASCII plus AT commands make touchscreen and terminal bring-up quick. A 2.4GHz wireless MODBUS-OTA option is available for drops where cable is impractical.
Engineered for the Ugly Side of a Panel
The DC 11-28V input is protected against reverse polarity, overcurrent, surge and automotive load-dump behind a DC 250V / 3000mA slow-blow fuse. Inputs, outputs and the RS-485 port are all isolated from internal logic, and the PCB is slotted for creepage: >6.5mm measured from relay terminals to the logic side against a >6mm requirement, with >2.2mm clearance against >2mm. EFT immunity is tested to 2kV - double the 1kV that IEC 61000-6-2 asks of industrial equipment - with ESD to 4kV, operation from -20 to 60C, and relay mechanical life above 100,000 operations. For sites with relentless EFT, the input-hardened "XS" order suffix strengthens the input stage. A safety-lock register (write ASCII "UL" to unlock, auto re-locks after each write) stops a stray Modbus write from changing the address or baud rate. Certification documents available on request.
Applications
Models & Ordering Information
Base Model
How to Select
- Choose the 12-in/8-out D3J0312 when a panel has up to 12 switch/limit/alarm points to read and up to 8 loads to drive on one board - the highest channel count and lowest per-point cost in the D3J03 series.
- For fewer points, step down to the D3J0308 (8-in/4-out), D3J0304 (4-in/2-out) or D3J0302 (2-in/1-out) to avoid paying for unused channels.
- Choose relay-type outputs for standard AC loads and where high isolation is needed; choose transistor-type outputs for inductive or high-current DC loads and when the PWM/PTO pulse function is required.
- When wiring multiple modules on the same RS-485 bus, set a unique slave address (1-247) on each unit and plan for bus termination resistors.
- For sites with frequent strong EFT interference or heavy inductive loads, order the input-hardened version (order-code suffix "XS") or add a supply filter/anti-EFT power supply, keeping the supply cable under 3m.
- Default shipped configuration is D3J0312M111 (all-relay output, pulse unavailable, no wireless); specify output type, pulse availability and wireless option at order time.
📘 Need the full method? NPN vs PNP Sensor Outputs Explained
When NOT to specify the D3J0312 — and what to use instead
Your control panel needs more than 12 inputs and 8 outputs on a single drop
Why not: D3J0312 is the highest channel-count model in the D3J03 family and has no larger combined sibling - it is fixed at 12 inputs and 8 outputs.
Use instead: Split the panel across two or more D3J0312 (or mixed D3J03) modules on the same RS-485 bus at different slave addresses (1-247), or move to a D4G0206 micro-PLC if you also need real cross-module logic.
You only need to monitor 12 points, or only switch 8 loads, without the other channel type
Why not: D3J0312 always pairs 12 inputs with 8 outputs on its 44-terminal, 158mm-long board; a monitoring-only or actuation-only application leaves a large part of the module unused.
Use instead: Use the pure-input D3J0116 (nearest available count) or the pure-output D3J0208 (exact 8-channel match) instead, sized to the point count you actually need.
You are treating the 8 input-linked outputs and the BRKFLG emergency brake as the certified safety system for a panel that interlocks many actuators
Why not: None of D3J0312's 8 outputs are OSSDs and the module carries no Type/SIL/PL rating; the linkage and brake (typical ~20ms response) run locally on the module without the host. Both run locally on the module without the host, which is exactly why they get mistaken for a safety function, but they are not one.
Use instead: Wire the actual safety function through a DA31 Emergency-Stop Safety Relay Module or DQSRN Safety Relay Module.
Any of the 8 outputs will drive a load beyond 8A, or an AC load above 0-220V
Why not: Relay outputs are rated DC 30V or AC 0-220V at 8A and transistor outputs DC 12-48V (normal) or DC 12-24V (high-speed) at 8A, with only a 10A absolute maximum even with the built-in flyback diode.
Use instead: Switch the heavier load through an external contactor or relay sized for it, driven from the D3J0312 output.
You need the 8 outputs to execute multi-condition, timed or sequenced logic across the 12 inputs rather than the fixed output-n-to-input-n pairing
Why not: Local logic is limited to that direct linkage, 5 jog/delay modes, and per-channel DINnCNT edge counting / DINnFLT filtering - there is no ladder or programmable logic engine on board even at this channel count.
Use instead: Use the D4G0206 micro-PLC for real programmable logic across the panel.
Your network standard is a fieldbus other than Modbus-RTU, such as Profinet, EtherNet/IP or CANopen
Why not: D3J0312's wired protocol is RS-485 Modbus-RTU by default (9600bps/8-even-1, address range 1-247), with Modbus-ASCII/AT commands and an optional 2.4GHz Modbus-OTA wireless link as the only alternatives.
Use instead: Choose an I/O module or gateway that speaks your fieldbus natively.
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.
- Mean time between failures (MTBF) for the module - not published
- Ingress protection (IP) rating of the enclosure - not stated in the source manual
- Full EMC compliance (radiated/conducted emissions, RF immunity) beyond the documented ESD/EFT/surge results - not published
- Resolution, accuracy and input voltage range of the 2 analog input channels - only described as voltage measurement, no numeric spec given
- PWM/PTO pulse output frequency range and step/pulse-count limits - no numeric value documented
- Wire gauge accepted by the 44 screw terminals - not stated
- Maximum number of RS-485 nodes per bus segment and maximum cable length - not stated
- Module weight (only L x W x H = 158 x 88 x 59mm is given) - not documented
Frequently Asked Questions
What does the D3J0312 do?
What's the difference between the relay and transistor output types?
Can the outputs run without a host controller?
How many analog inputs and pulse outputs does the D3J0312 have?
How do I unlock the module to change protected registers?
What communication options does the D3J0312 support besides RS-485?
Does the D3J0312 meet industrial EMC requirements?
Works Well Together
On the same machine or line, D3J0312 is typically ordered together with: Proximity Sensors · Photoelectric Sensors · Laser Distance Sensors
D6.5 Series Inductive Proximity Sensors (Ultra-Short 18mm / Y-Type / 35mm / 45mm)
6.5mm-diameter inductive proximity sensors for tight-clearance mounting where M8 sensors won't fit.
BGS-CX441 / BGS-CX442 Background Suppression Photoelectric Sensor
Wire-adjustable BGS sensor with 2 mm or 15 mm spot, 10-300 mm range, published black/white differential distance.
DDA-Y & DDB-Y Industrial Laser Distance Sensor (Phase-Shift)
Phase-shift laser distance sensors: 0.2-100 m range, millimeter accuracy, RS485 Modbus RTU, switching or analog output.
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