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Modbus TCP Server connection limitations

Based on Modbus TCP documentation, MB_TCP_Server function block has a limitation of one client accessing the server. What are the other options if I need multiple Modbus clients talking to the server running on the PLC? I have AXC F 3152 controller.

Comments

  • Here is the answer from the developers of the Modbus TCP library (you can also contact them using the "Contact" button on the PLCnext Store product page):
    You can run more than one client or server at one device but you can only connect one MB_TCP_Client with one MB_TCP_Server at the same time.
    If you want to use more then one client at the same time you need for each Client one instance of the MB_TCP_Server.

    If you want to use same data for all MB_TCP_Server, just connect the same array with all your MB_TCP_Server.
    Refer to chapter Startup example - Multiple client.
  • edited March 2022
    Martin, Thank you for your reply.
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