integration

WaveShare Modbus Digital Input & Relay

8-channel relay control and 8-channel digital input monitoring over Modbus TCP

Full Modbus integration for the WaveShare PoE ETH Relay (B) module. Relay control with sequencing, digital input monitoring with optical isolation feedback, and two-way device status.

Q-SYS plugin for the WaveShare Modbus PoE ETH Relay (B) module, providing 8 channels of relay output and 8 channels of digital input over Ethernet. Uses the Modbus TCP protocol on port 502 for reliable, bidirectional hardware control and monitoring.

This plugin is designed for the relay and digital input variant of the WaveShare PoE Ethernet range. If you’re using a relay-only WaveShare module (8, 16, or 30 channel), see the WaveShare Ethernet Relays plugin instead.

Relay Control

Individual relay toggle (on/off) for all 8 channels
Relay flash (pulse on, auto-off)
All-on / all-off group control
Full two-way feedback on relay state

Digital Input Monitoring

8 optically isolated digital input channels with real-time state monitoring. The plugin checks the device status at a configurable rate and displays each input’s state as an LED indicator / Boolean.

The digital inputs can be triggered in two ways:

Dry contact closure: Short the DI terminal to DGND via a switch or dry contact
Voltage driven: Apply a voltage source (5 to 36V DC) to the COM terminal, with the DI terminal switching to DGND

Device Setup

The device ships in RTU mode on port 4196. This will not work with the plugin out of the box. You must configure the device via its web interface before connecting:

Change the Device Port from 4196 to 502
Change the Protocol from None to Modbus TCP to RTU
Enable Multi-host mode
Assign a static IP address on your control network

See the setup guide (included in the download) for full instructions and a screenshot of the correct settings. Power the device via PoE or an external 7-36V DC supply.