With the Modbus Slave feature, Xpanel can act as a Modbus server (Slave) device. Similar to the [Data Server] feature, Xpanel also has dedicated memory for acting as a Modbus Slave. When a Modbus client (Master) makes a request, the Slave will respond with a frame containing the requested data. You can use Modbus RTU or Modbus TCP with this function.
The Modbus memory buffer consists of ‘Coils’ (Max Size: 5,000) and ‘Holding Register’ (Max Size: 10,000) areas. You can only register digital tags to the ‘Coils’ area, while you can only register analog and string tags to the 'Holding Register' area.
To use an Xpanel device as a Modbus Slave, the Modbus Master device will also need to be configured. If the Master device is an Ativa PLC, you can configure it using the Ativa software package. See the Additional Configuration section for more information.