This guide gives a example of how to check that OPC is receiving commands and transmitting to controller.
When integrating with third party applications and commands from this application are not being received by controller and this test using softing tool is necessary to verify where the issue lies.
Copy the command highlighted above in Bold into the value box, edit the panel node and control element details as required and select OK.
If the command is correct and matches with the OPC info from the panel then the output will switch as required.
The command structure and commands available are detailed in the OPC technical documentation, also included are command examples.