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Unity Pro error trying to connect to a PLC. "This isn't a valid PLC Address, or PLC is busy , or media is off."

Published date: 03 December 2019

    Error message connecting to a PLC.

Product LIne:

   Unity Pro software


  This can be caused by an incompatiblity of the PLC's firmware version in the Unity Pro project and the version of the firmware that resides in the controller.
It can also be a communications timeout.


  Change the version of the firmware in the Unity Pro project.
  To change the version in the Project, double click on the CPU from the Project Browser and drop down the box above the rack.  
  Choose the version of the firmware that is currently in the PLC and rebuild the project.

  Verify that communications protocol is working properly, USB, Modbus Plus, correct Ethernet address, etc.

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