Faults in HMI, PLC response problems

HMI always shows this message what will be the reason for this fault. It is not the problem of the communication cable I already change that, please give a solution for this problem


  • Use a twisted pair cable, this problem could be because of harmonics, and check earthing in the panel can be also helpful.

  • Change the parity bit and then upload

  • Check any VFD or electronic device harmonic is preset

  • Check communication parameters

  • Check if you have external 24 VDC in the plc

  • Check the IP’s of both HMI and the PLC