Troubleshooting/diagnostics

  1. Check the hardware and software requirements described in this documentation (TwinCAT version, CE image version etc.);
  2. Compare the interoperability check list of control station and substation;
  3. Check the IO configuration and mapping of PLC variables in TwinCAT System Manager (configuration of serial interface, baudrate, parity, stoppbits settings). Compare them to the parameters set in the substation;
  4. Check whether the FB_IEC870_5_103TProtocol() function block issues an error code. The documentation for the error codes can be found here: Overview of error codes;
  5. Check the protocol parameters that are transferred to the function block (link address, link address octet size, FRAMELength etc.). Compare them to the parameters set in the substation;
  6. Check the max. configured ASDU length (instance of ST_IEC870_5_103TBuffer, TX/RX data buffer). Compare them to the parameters set in the substation.
  7. Check the configured data points (type, ASDU address, function number, information number etc.);
  8. Check if the other communication partner issues an error code;
  9. Activate the debug output during connection establishment and/or of ASDU data. Open the TwinCAT System Manager and activate the LogView window. Analyze/check the debug output strings;