Modbus TCP communication error with certain IP address

[Rene]

Help wanted!!!
After replacing older V570-57-T40B PLC to new one (V570-57-T20B with latest firmware, project file created earlier with Visilogic version 7.0.3 is converted now to 9.5.0) the Modbus slave communication simply does not work anymore. The V570 Modbus TCP slave connection doesnt work with PLC IP address 193.142.204.85. Is there some new address range limitations for Modbus? Socket status monitoring shows me that socket is connected, but PLC simply doesnt answer to Modbus data requests from SCADA system. Ethernet connection itself is OK (Visilogic can communicate with IP address 193.142.204.85, but Modbus not)
Everything worked well with older PLC and firmware and there is no changes made in PLC project and SCADA software.

 

[linxchas]

From visilogic menu try Build>Build All, then download project again.

From my experience, Modbus never works well after conversion without rebuilding the project.

[Joe Tauser]

If your SCADA software has a spot for the Slave ID set it to 255.

 

Joe T.