This page describes adding a modbus RTU device using the é!COCKPIT runtime. In case a function block for your specific device is not present yet in this project. Please consider reading the RS485 tips and tricks page if this is your first time connecting a RS485 device.
In order use the onboard PLC serial port from the PLC runtime this needs to be configured from the web based management tool:
Note that it's necessary to reboot the controller after a change to this setting.
Make sure the following libraries are present in the project:
WagoAppPlcModbus
A specific implementation example can be found inside the project in the 'PLC_PRG_RS485' program.