Abstract: In view of the fault of frequent jumps of telemetry data in several 500 kV substations, the telemetry data transmission mechanism is analyzed in detail, and then the fault is located by means of message acquisition and analysis. By comparative tests under a simulated field environment, it is determined that the cause of the failure is the double port RAM error check of the remote operating device and the interruption of the soft floating-point value conversion of the measurement and control device. Finally, through hardware replacement and software upgrade, the disposal of faults of telemetry data frequent jumps is realized, which guarantees safe and stable operation of power grid.