Modbus RTU 16-Channel Relay Module

WaveshareSKU: WAV-24921
Sale price £42.60
incl. VAT
excl. VAT
Only 14 units left

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WaveshareUSB to RS485/422 Industrial Grade Isolated Converter
Sale price £17.40 incl. VAT excl. VAT

With 16 individual relay channels, this module provides an extensive capacity to manage many devices or equipment simultaneously. Whether you're controlling pumps, motors, heaters, or other machinery, the relay module offers a comprehensive solution for orchestrating various processes with precision. Equipped with built-in protection circuits including power supply isolation, ADI magnetical isolation, resettable fuse, and TVS diode, this module safeguards your equipment and data against power surges, electromagnetic interference, and short-circuits.

It supports the widely-used Modbus RTU protocol, allowing you to configure the device address within the range of 1 to 255. Furthermore, this module can be seamlessly integrated into existing setups, as multiple devices can be cascaded on an RS485 bus. This cascading capability simplifies complex installations and optimises communication across your network of devices.

Through the configurable device address and cascading functionality, you have the flexibility to create intricate automation systems tailored to your exact needs. Its extensive relay capacity, advanced protection features, Modbus RTU compatibility, configurable device address, and cascading capability make it an invaluable asset in managing complex processes while ensuring equipment longevity and data integrity.

Note: It is recommended to purchase the USB TO RS232/485/TTL or USB TO RS485 at the same time for easy testing.


  • Configurable device address (1~255), multi-devices can be cascaded on RS485 bus
  • Features flash-on, and flash-off function, by passing argument to the command, it is possible to turn on the relay for a while and then close it automatically
  • Onboard unibody power supply isolation, provides stable isolated voltage, needs no extra power supply for the isolated terminal
  • Onboard unibody ADI magnetical isolation, allows signal isolation, high reliability, strong anti-interference, low power consumption
  • Onboard resettable fuse and TVS (Transient Voltage Suppressor), effectively suppress surge voltage and transient spike voltage in the circuit, provides over-current/over-voltage proof, lightning proof & anti-electrostatic
  • Onboard Optocoupler isolation, prevent the relay from being interfered by high-voltage circuit
  • Onboard 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

Connection Example - AC 220V Device & A DC 30V Device


Operating Voltage 5V
Communication Interface RS485
Baudrate 4800, 9600, 19200, 38400, 57600, 115200, 128000, 256000
Default Communication Format 9600, N, 8, 1
Relay Channels 16
Contact Form 1NO 1NC
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


Package Contents

  • 1x Modbus RTU Relay 16CH
  • 1x US plug 5V 2A Power supply (with EU head adapter)

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