ModBus Warning Exception code received: EC=1 FC=1

[jeissonsierrac]

Dear all,

We have two projects with Wincc OA 3.16 P002 but , log viewr shows this warning:

WCCOAmod (2), (Time Stamp), SYS, WARNING, 54, Unexpected state, ModModbusMaster, processResponse, 172.16.83.4: Exception code received: EC=1 FC=1 for UA: 1 Ref: 0
WCCOAmod (2), (Time Stamp), SYS, WARNING, 54, Unexpected state, ModModbusMaster, processResponse, 172.16.83.4: Exception code received: EC=1 FC=1 for UA: 1 Ref: 0
WCCOAmod (2), (Time Stamp), SYS, WARNING, 54, Unexpected state, ModModbusMaster, processResponse, 172.16.83.4: Exception code received: EC=1 FC=1 for UA: 1 Ref: 0

Any suggestions to resolve this warning.

Thanks for your help.

[mkerk]

Hello Jeisson,

In the WinCC OA documenatation in chapter "Drivers" --> Modbus/TCP --> Modbus/TCP driver details" you can find a table, which describes the error meesage of the driver.

the error message "...ModModbusMaster ...Exception code received: EC= .." means the following: Wrong response to a particular request. If too many errors of such kind occur, the connection is closed and reopened.

Please check the connection to the PLC 172.16.83.4 and the state of this PLC

BR,
Mousser

[Gertjan van Schijndel]

Take a look at this answer from a similar topic.