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Entry type: FAQ Entry ID: 109768961, Entry date: 11/26/2019

How do you clear problems with the Modbus TCPI/IP communication with WinCC V7.X?

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Help for addressing the Modbus TCP/IP communication.

You have connected a Modbus device to WinCC V7.X and WinCC V7.X reports an addressing error with the Modbus address.

The Modbus TCP/IP channel was tested together with Schneider controllers. This is why the types of the Schneider controllers are specified in the settings of the Modbus TCPI/IP channel. Communication to other Modbus devices is possible as long as they comply with Modbus specifications.

Remedy for incorrect addressing
Proceed as follows to clear addressing problems:

  1. In the WinCC Explorer you open the Tag Management editor.
  2. Open the Tag Management tree structure and under Modbus TCPIP you select your channel unit and your connection.
  3. Right-click your connection to open the connection parameters.
  4. Change the CPU type to one of the other two types and test your connection.

Further information is available in the WinCC manual: 109760748 

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