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  • ernesto881124 - 2023-09-13

    Hello good morning everyone
    I would like to ask a question, is it possible to directly connect a device that only contains modbus RTU communication through an R-45 connector, directly to the PC? Or would you need an intermediate device to achieve communication? It would be of great help to me because I cannot achieve communication between the Codesys simulator plc and a Fuji Frenic mini VFD, please help me if anyone has had the same experience.
    Thank you so much

  • TimvH

    TimvH - 2023-09-14

    You will need a USB to RS485 converter to connect the PC to the Modbus RTU Slave Device.

    In Windows this converter will be recognized as Serial COM poort (e.g. COM2, or COM3, see the windows device manager to find this out). Select this port in your CODESYS application.

    On the PC you need to use the CODESYS Control Win (SoftPLC) to run your application. It will not work in simulation mode, because then the Modbus Communication will not be activated.

  • marekxc - 2023-09-14

    Or You will need a "RS232/485 TO ETH" converter to connect the PC with ethernet and second side eg RS485 with Modbus RTU. Please note that sometimes USB/RS converters do not work with windows 10 11. You need to make sure and sometimes use older USB/RS winows hardware drivers. Only then try with Codesys Control win on your laptop.


    Last edit: marekxc 2023-09-14
  • ernesto881124 - 2023-09-14

    Thank you very much for the help and for the response, I already ordered the RS-485/232 to USB converter to see if I can achieve communication, if not I will try with Ethernet instead of USB. thank you very much again for your answers


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