Modbus RTU 32-Channel Relay Module

WaveshareSKU: WAV-25140
Sale price £59.70
incl. VAT
excl. VAT
Only 9 units left

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This 32-channel Relay Module has an RS485 bus system and uses the Modbus RTU protocol for fast and secure communications. It is equipped with a power supply isolation, magnetical isolation, resettable fuse, and TVS diode, providing safety and durability.

It has a configurable device address range from 1 to 255, allowing multiple devices to be cascaded on a single RS485 bus for streamlined integration. The flash-on and flash-off function provides temporal relay activation, giving automatic control with precision.

Supporting a wide input voltage range from 7 to 36V, the module includes a voltage regulator chip for consistent performance without the need for an additional power supply for the isolation terminal. Its unibody design combines power supply and magnetical isolation, fostering signal integrity, minimal interference, and low power consumption.

Note: The power supply adapter is NOT included. You can get one here


  • Configurable device address (1~255), multi-devices can be cascaded on RS485 bus
  • Features flash-on, and flash-off functions, it is possible to turn on the relay for a while and then close it automatically via the command
  • Voltage regulator chip, supports 7~36V wide voltage power supply
  • Unibody power supply isolation, provides stable isolated voltage and needs no extra power supply for the isolated terminal
  • Unibody magnetical isolation, allows signal isolation, high reliability, strong anti-interference, low power consumption
  • Resettable fuse and TVS (Transient Voltage Suppressor), effectively suppress surge voltage and transient spike voltage in the circuit, provide over-current/over-voltage proof, lightning proof & anti-electrostatic
  • Optocoupler isolation, prevent the relay from being interfered with by high-voltage circuit
  • Dedicated relay driver chip, with built-in freewheeling diode protection, the driving ability is stronger and more stable
  • Reverse-proof circuit, prevent the circuit from being damaged accidentally by incorrect connection
  • High-quality relay, contact rating: ≤10A 250VAC/30VDC
  • Rail-mounted ABS case, easy to install, safe to use
  • 3 LEDs for indicating the MCU status and signal transceiving status


Operating Voltage 7~36V
Communication Interface RS485
Baudrate 4800, 9600, 19200, 38400, 57600, 115200, 128000, 256000
Default Communication Format 9600, N, 8, 1
Relay Channels 32
Contact Form 1NO 1NC
Contact Rating ≤10A 250VAC/30VDC
Communication Protocol Standard Modbus RTU protocol
RS485 Address 1~255
LED Indicators STA: MCU indicator, keep flashing when the MCU normally working
TXD: TX indicator, lights up when sending data
RXD: RX indicator, lights up when receiving data

Connection Example - AC 220V & DC 30V


Package Contents

  • 1x Modbus RTU 32-Channel Relay Module

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