Siemens S7 ISOTCP FAQ

COTP connection is disconnected, error code 10150

  • Check whether the S7 node configuration parameters configured in Neuron match the PLC, such as CPU rack number (slot), CPU slot number (rack), etc.
  • S7 lower layer protocol cannot be recognized, and the protocol layer connection cannot be established. Check whether the connection port supports the standard S7 protocol.

Read tag value error, error code 10103

  • Protected tag, need to configure permissions in PLC.

Read tag value error, error code 10105

  • The tag in PLC does not exist

Read tag value error, error code 3002

  • Check whether the server where Neuron is installed can communicate with PLC. If it can ping, you can try to use the telnet tool to test the PLC port.