DT-R002 2-Channel Ethernet Relay Module WiFi LAN RS485 Modbus RTU DIN Rail Housing

Quick Introduction Upgrade your automation reliability with the DT-R002 (RS-485 Edition). This fully enclosed, DIN-rail mountable unit is more than just a smart switch; it's a protocol gateway. Powered by an ESP32, it provides simultaneous Ethernet and WiFi connectivity to ensure your commands are never interrupted. This specific model includes an RS-485 interface, allowing it to act as a Modbus Master to read external sensors or a Modbus Slave to be controlled by your PLC, all while managing two local high-power relays.

Detailed Specifications

• Model: DT-R002-485-CASE (RS485 Variant with Housing).

• Controller: ESP32.

• Network Interfaces:

  • Ethernet: RJ45 (10/100 Mbps) with magnetic isolation.

  • WiFi: 2.4GHz 802.11 b/g/n (AP + Station Mode).

• Serial Interface: RS-485 (A/B) for Modbus RTU communication.

• Outputs: 2x Relays (NO/NC, 10A 250VAC).

• Inputs: 2x Opto-isolated Digital Inputs (Dry/Wet Contact).

• Enclosure: Industrial ABS DIN Rail Case (C45 Standard).

• Power Input: 12V DC or 24V DC (Non-PoE, Screw Terminals).

• Protocols: MQTT, Modbus TCP (Ethernet), Modbus RTU (RS-485), HTTP CGI.

Quality Advantage & Differentiation: Why choose the RS-485 Enclosed Version?

1. RS485 Bridge Mode: Unique to this variant, the "Transparent Transmission" feature allows you to send serial commands via Ethernet (TCP/UDP) directly out the RS485 port. It effectively replaces a separate "Ethernet-to-RS485" converter.

2. Protection: The included DIN rail case protects the PCB from dust, accidental shorts, and physical damage in electrical cabinets.

3. Hybrid Connectivity: Unlike standard Modbus relays that only use RS-485 wires, this unit can be controlled wirelessly via WiFi or wired LAN, providing flexibility for retrofit installations where running new LAN cables is difficult.

Key Applications & Usage

• Modbus Gateway: Use the DT-R002 to read a daisy-chain of RS-485 Soil Moisture Sensors or Energy Meters and report the data to Home Assistant via MQTT.

• Hybrid Gate Controller: Control the gate motor with the relays, read the "Gate Open/Closed" limit switch with the Digital Inputs, and communicate with a long-range card reader via RS-485.

• Industrial Watchdog: Monitor critical equipment via Digital Inputs. If a fault is detected, trigger a Relay to reset power and send an MQTT alert instantly over Ethernet.

What's Included & Required

• Included: 1x DT-R002 Relay Module (RS485 Version), 1x DIN Rail Plastic Housing (Pre-assembled),1x RC Snubber Kit

• Required: 12V/24V DC Power Supply, Ethernet Cable, RS-485 Cabling (if using serial features).

The "Virtual Technician" Support Panel

• ⚠️ FIRMWARE TYPE CHECK (Crucial):

  • Standard Firmware (Default): Comes locked. Excellent for Modbus/MQTT users. Cannot be flashed with ESPHome.

  • Development Firmware: If you plan to code your own firmware (Arduino/ESPHome), you MUST contact us to ship the "Dev/Test Version".

• ⚠️ RS485 WIRING TIP:

  • Always use twisted pair cable for RS-485 (Data+ and Data-).

  • If the cable run is long (>100m), you may need a 120-ohm termination resistor at the far end of the bus (not included on the board).

• ⚠️ INPUT CONFIGURATION:

  • The 2 Digital Inputs are active-low by default. You can configure them in the Web UI to "Link" to the relays (e.g., Input 1 ON -> Relay 1 ON) without needing an external controller.

EXTERNAL RESOURCE INTEGRATION

• 1. Official Manual & SDK:

  • Resource Name: Dingtian Relay Board SDK & User Manual

  • Link: Download SDK (Zip)

  • Description: Essential documentation for Register Maps (Modbus), HTTP Commands, and Configuration Tools.

• 2. Configuration Tool:

  • Resource Name: Relay Upgrade & IP Tool

  • Link: Download Tool

  • Description: Use this to find the device IP address if you forget it or if DHCP is enabled.

• 3. Firmware Guide (Dev Version Only):

  • Resource Name: Custom Firmware Repository

  • Link: GitHub - Relay Dev Demo

  • Description: Reference code for flashing your own firmware (Requires Unlocked/Dev Board).