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waveshare Modbus RTU Relay Module 32 Channels (RS485, Industrial)
Industrial Control (B2B)

waveshare Modbus RTU Relay Module 32 Channels (RS485, Industrial)

5.0(5 reviews)

$84.99reference price

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Best for

Automating many outputs (up to 32) from a single Modbus master, in installations that already run an RS485 bus.

  • 32 channels
  • RS485 Modbus RTU
  • Optical isolation

What is it and what's it for?

It's like the 8-channel relay module a hobbyist would build, but at industrial scale: 32 "remote-controlled switches" on one board, each controlled over Modbus, the language industrial machines use to talk to each other, like a shared phone line where each device has its own number.

Real-world use cases

At home

It's not a typical home product, but someone building a very large home-automation system (many independent lights and devices) could use it to centralize control of all of them.

In a business or workshop

A plant that needs to turn 32 different devices on and off (lights, small motors, solenoid valves) from a single central control system, using the same RS485 bus already installed.

How to avoid buying the wrong one

  • Has a configurable address (1 to 255), so you can put several of these modules on the same bus without interference — keep good notes on which address you assigned each one.
  • Has real optical isolation: it protects the control side (low voltage) from the power side (whatever's being switched on/off).
  • With only 5 reviews, it's a solid technical purchase on paper but still without much track record from other buyers.

The investment takeaway

Buying 32 separate relays with their own protections would cost much more and take up far more space than this integrated module — for a large installation, consolidating onto one board with real isolation is the most cost- and space-efficient option.

waveshare Modbus RTU Relay Module 32 Channels (RS485, Industrial)

$84.99reference price

See current price on Amazon

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