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Control Expert (formerly Unity Pro) error trying to connect to a PLC. "This isn't a valid PLC Address, or PLC is busy , or media is off."
Issue:
Error message when attempting to connect to a PLC.

Product LIne:
Control Expert software  (formerly Unity Pro )

Resolution:
This error means simply means that whatever address you are looking for is not responding. You would get this same error if trying to connect with no cable or if the cable you are using is bad.

In the 'Set Address' box, make sure that the check mark is next to PLC and not simulator.

Check for a Typo in address field.

Verify that communications protocol is working properly, USB, Modbus Plus, correct Ethernet address(make sure ping responds), etc.

If using the USB port on an M340, Quantum or M580 CPU, the address is SYS and Media is USB.
FAQ for M340 https://www.se.com/us/en/faqs/FA233491/
FAQ for M580 https://www.se.com/us/en/faqs/FA240733/

If using the Ethernet port on CPU/Comm Module, Address needs to be in the xxx.xxx.xxx.xxx (leading zeros not mandatory) format and Media is TCPIP.
FAQ for M340 https://www.se.com/us/en/faqs/FA376594/
FAQ for M580 https://www.se.com/us/en/faqs/FA374996/
FAQ for Ethernet troubleshooting https://www.se.com/us/en/faqs/FA199311/

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