D3J0202 Modbus
Compact 2-channel Modbus-RTU/RS-485 output module with relay or transistor outputs plus up to 2 PWM/PTO pulse channels.
🔍 Click to enlarge · 1/4ℹ Product photo shows KEANSHI (金恩士) housing markings — KEANSHI is a DAIDISIKE (戴迪斯科) group brand, and these D3-series serial I/O modules are supplied under it.
Technical Specifications
| Type | ASIC-based Modbus-RTU/RS-485 digital output module, pure output (no input acquisition) |
|---|---|
| Default order code | D3J0202M111 (all-relay output, pulse unavailable, no wireless) |
| Product ID / default slave address code | 0x3202 |
| Input | None (pure output type) |
| Output channels | 2 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 |
| Output coil mapping (2-channel model) | Uses the first 8 coils (<= 0x0007); unimplemented coils read as 0 |
| Supported function codes | 0x01 read coils, 0x05 write single coil, 0x0F write multiple coils, 0x03 read holding registers, 0x06 write single holding register, 0x10 write multiple holding registers, 0x16 mask write, 0x17 read/write multiple holding registers, 0x04 read input registers, 0x11 report device ID |
| Supply voltage | DC 11-28V |
| Supply ripple | < 1Vp-p |
| Supply current | < 1500mA |
| Communication terminal stress (normal) | DC 0-5V |
| 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 |
| 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 |
| 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 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) |
| Module dimensions | 54 x 88 x 59mm (tolerance +/-5%) |
| Terminal pitch | 5.08mm |
| Terminals | 6 screw terminals, 1 USB port, 3 indicator LEDs |
Overview
The D3J0202 is a 2-channel Modbus-RTU/RS-485 digital output module built around an ASIC core, for engineers who need to switch remote loads such as pumps, solenoid valves, contactors and indicator lights from a central controller over a single 485 bus. It is a pure-output device: it does not read external digital signals, and each of its 2 fully isolated output channels can be ordered as relay type or open-drain transistor type.
Each channel switches DC 30V or AC 0-220V at 8A in relay form, or DC 12-48V at 8A in transistor form with a built-in 10A freewheeling diode, and the module additionally supports up to 2 high-speed PWM/PTO pulse outputs on DO0/DO1 for motor speed control or stepper drive. It runs on DC 11-28V supply, communicates by default at 9600bps/8-even-1 over RS-485 Modbus-RTU with a slave address range of 1-247, and also ships with a USB port that supports MODBUS-ASCII and AT commands, with an optional 2.4GHz wireless MODBUS-OTA.
Features & Benefits
8A Contacts Drive the Load Directly - No Interposing Relay
Each of the 2 channels brings out its own NC / COM / NO terminals and switches DC 30V or AC 0-220V at 8A, so a pump contactor, an AC solenoid valve or a 220V lamp wires straight to the module. That removes the interposing relay, its base and its panel space from your bill of materials, and removes one more failure point from the cabinet.
Relay or Open-Drain Transistor, Chosen at Order Time
The same D3J0202 ships as relay type or MOSFET type - the 1st digit of the [ddd] order code (1=relay, 2=transistor). The transistor version is open-drain, rated DC 12-48V / 8A, and carries a built-in 10A freewheeling diode, so it drives a heavy-duty solenoid or a DC motor directly with no external flyback diode to source, mount or get wrong.
2 PWM/PTO Pulse Channels Included - A Motor Driver in the Same Box
Order the pulse-enabled code (3 = DO0 only, 4 = DO0 and DO1 as high-speed transistors) and the module also outputs standard PWM for speed, dimming or power control and standard PTO pulse trains for stepper drive, programmed through the PGM register area from 0x0100. Two channels cover a small dual-axis stage, or one speed-controlled motor plus one on/off load - without adding a separate pulse card to the bus.
Plain Modbus-RTU - Working in Minutes, No Driver to Write
Defaults are 9600bps / 8-even-1, slave address 0x02, with the full 300-115200bps range, none/odd/even parity, 1 / 1.5 / 2 stop bits and addresses 1-247 all selectable. The 2 outputs map to coils 0x0000-0x0007, so any PLC, HMI or gateway drives them with standard function codes 0x05 or 0x0F and reads them back with 0x01. Nothing proprietary to license or implement.
Per-Channel Jog/Delay Timer Runs Without the Host
Every channel has 4 coils (DOUTnDV value, DOUTnRST reset, DOUTnFV force value, DOUTnFEN force enable) plus a DOUTnCFG register from 0x0080, and can be configured as a simple delay timer for timed power-on, pulse triggering or automatic switch-off. Timing runs on the module, so the host does not have to hold a scan-rate-accurate timer open per output, and the power-up state of each channel is configurable rather than arbitrary.
SAFELCK Keeps a Noisy Bus From Rewriting Your Configuration
Sensitive registers (NAME, serial config, wireless settings) stay locked until you write ASCII "UL" (0x554C) to SAFELCK at 0x000E, and the module re-locks itself after every single write. A CRC or checksum error on the bus, or a frame addressed to another module, re-locks it too. On a long 485 trunk with EFT-prone drives nearby, a garbled frame cannot silently change a node's baud rate or address.
Isolation and Protection Verified by Number, Not by Adjective
The RS-485 port and both outputs are electrically isolated from internal logic - under 250V in normal use, type-tested to DC 1000V for 60s on the relay version. The supply survives reverse polarity, over-current, surge and automotive load dump, and is backed by a DC 250V / 3000mA slow-blow fuse. On the PCB, high-voltage-side slots take creepage to over 6.5mm against a 6mm requirement and clearance to over 2.2mm against 2mm (pollution degree 3, IEC 60950) - margin you can see on the board.
USB Port Doubles as Your Commissioning Tool - and Your 485 Master
Beyond RS-485 there is a USB port that configures the module, updates firmware and works as a USB-to-serial adapter; plug it in and the module answers at address 0x01 while its RS-485 side flips to master mode, so one laptop can commission a whole trunk. MODBUS-ASCII suits touchscreens and PLCs, AT commands get a test rig running in minutes, and an optional 2.4GHz self-networking MODBUS-OTA link covers spots where pulling cable is not realistic. All of it in a 54 x 88 x 59mm body on DC 11-28V at 40mA typical, rated -20 to 60 degrees C.
Applications
Models & Ordering Information
Base Model
How to Select
- Choose the 2-channel D3J0202 when you have only 1-2 output points to control, or need a compact end node on a bus; for more points, step up to the 4-channel D3J0204, 8-channel D3J0208, or 14-channel D3J0214.
- Choose relay type when you need to switch AC 220V loads, need physical contact isolation such as for contactors, indicator lights or AC valves, or the controlled equipment is sensitive to the brief power-up/power-down pulse.
- Choose transistor type for inductive DC loads, when you need long service life under high-frequency switching, or when you need the PWM/PTO pulse function, since pulse output requires the transistor type.
- To use the pulse output function, order the configuration with pulse enabled (DO0/DO1 set as high-speed transistor); both pulse channels are then available on the D3J0202.
- Default shipped configuration is D3J0202M111 (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 D3J0202 — and what to use instead
The application also needs to sense a limit switch, float switch, or feedback signal from the equipment being driven, in addition to switching 1-2 outputs
Why not: The D3J0202 is a pure-output device - its own spec lists Input as "None (pure output type)"; its 2 channels are output-only (relay or transistor) with no digital input acquisition circuitry at all
Use instead: D3J0302 (combined digital input/output module) or a D3J0104 input module wired on the same RS-485 trunk
A workstation has three or more independent points to switch, such as a 3-valve manifold plus a beacon light
Why not: The D3J0202 brings out only 2 fully isolated output channels (2 sets of NC/COM/NO terminals), and its coil map stops at 0x0007
Use instead: D3J0204 (4-channel), or D3J0208/D3J0214 for larger point counts
The load is a 220V AC solenoid valve or contactor coil, but the module was ordered as the transistor-output variant
Why not: On the D3J0202, transistor (open-drain) output is rated DC 12-48V / 8A only and does not switch AC voltages; only the relay-type output is rated for DC 30V or AC 0-220V at 8A
Use instead: order the D3J0202 relay-type variant (order-code first digit = 1)
The connected load runs at or above 8A continuous, or has a heavy inrush beyond the contact rating
Why not: Both output types on the D3J0202 are rated at 8A continuous; the transistor type's 10A figure is only its absolute-maximum/momentary rating (DC 55V/10A), not a continuous duty rating
Use instead: switch the load through an external contactor or motor starter sized for the actual current, triggered from a D3J0202 output
The output is meant to form part of an emergency-stop circuit or a safety-guard interlock
Why not: The D3J0202 carries no Type/SIL/PL safety rating in its published spec, and its relay/transistor contacts are ordinary industrial outputs, not OSSDs
Use instead: DA31 Emergency-Stop Safety Relay Module or DQSRN Safety Relay Module
The host system runs a fieldbus other than Modbus-RTU, such as Profinet, EtherCAT or CANopen
Why not: The D3J0202's only communication interfaces are RS-485 Modbus-RTU, a USB port (Modbus-ASCII/AT commands), and an optional 2.4GHz Modbus-OTA wireless link - no other protocol stack is built in
Use instead: add a Modbus-to-fieldbus gateway ahead of the module, or check with sales for a matching fieldbus product line
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.
- Relay electrical (contact) life specifically under rated 8A resistive and inductive loads, as distinct from the published mechanical-life figures
- MTBF for the D3J0202 module
- Relay manufacturer and part number used inside the D3J0202
- Recommended terminal wire gauge (AWG/mm2) and screw-terminal torque for the NC/COM/NO terminals
- Ingress protection (IP) rating of the enclosure
- Maximum number of RS-485 nodes and maximum cable length validated on one bus segment
- Module net weight
- Specific certification marks obtained (e.g. CE, UL, RoHS) beyond in-house IEC 61000-6-2 immunity testing
Frequently Asked Questions
What does the D3J0202 do?
Can the D3J0202 read digital input signals?
What's the difference between the relay and transistor output types?
How do I use the PWM/PTO pulse output?
What happens to the outputs at power-up or power-down?
How do I unlock the module to change protected registers?
Does the D3J0202 meet industrial EMC requirements?
Works Well Together
On the same machine or line, D3J0202 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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B2J0201 Economical Trigger Delay Module
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B2J0302 Enhanced Single MODBUS-485 I/O Module
Enhanced single-channel MODBUS-RTU/RS-485 I/O module: 1 digital input, 2 analog inputs, 1 relay or transistor output, AT command support and a 5V sensor supply — the successor to the discontinued B2J0301.