How To Fix /SCWM/MFS122 - Unable to reach PLC &1 (&2); restart of communication channel &3

SAP Error Message - Details

• Message type: E = Error

• Message class: /SCWM/MFS -

• Message number: 122

• Message text: Unable to reach PLC &1 (&2); restart of communication channel &3

Self-Explanatory Message

Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of messages in the SAP system have a message text, however this is frequently insufficient to comprehend or resolve the problem.

To make things easier, more detailed information is frequently added to describe the issue, how to fix it, and the necessary steps or configuration modifications.

Unfortunately, there isn't any extra information in this error notice.

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Smart SAP Assistant

• What is the cause and solution for SAP error message /SCWM/MFS122 - Unable to reach PLC &1 (&2); restart of communication channel &3 ?

  The SAP error message /SCWM/MFS122 Unable to reach PLC &1 (&2); restart of communication channel &3 is related to the integration between SAP Extended Warehouse Management (EWM) and a Programmable Logic Controller (PLC) through the Manufacturing Execution System (MES) interface. This error indicates that the SAP system is unable to establish or maintain communication with the specified PLC.
  Causes:
  
  Network Issues: There may be network connectivity problems between the SAP system and the PLC.
  PLC Configuration: The PLC may not be configured correctly or may be offline.
  Communication Channel Issues: The communication channel (e.g., TCP/IP, OPC) may be down or misconfigured.
  Firewall Settings: Firewalls may be blocking the communication ports required for SAP to communicate with the PLC.
  SAP Configuration: Incorrect settings in the SAP EWM configuration for the MFS (Material Flow System) interface.
  PLC Software Issues: The PLC software may have crashed or is not functioning properly.
  
  Solutions:
  
  Check Network Connectivity: Ensure that the network connection between the SAP system and the PLC is stable. You can use tools like ping to test connectivity.
  Verify PLC Status: Check if the PLC is powered on and operational. If it is offline, restart the PLC.
  Review Communication Channel: Check the configuration of the communication channel in SAP and ensure it is set up correctly. Restart the communication channel if necessary.
  Firewall Configuration: Ensure that the firewall settings allow traffic on the ports used for communication between SAP and the PLC.
  SAP Configuration Review: Review the MFS configuration in SAP EWM to ensure that all settings are correct and that the PLC is properly defined.
  Check PLC Logs: If available, check the logs on the PLC for any errors or issues that may indicate why communication is failing.
  Restart SAP Services: In some cases, restarting the relevant SAP services may help resolve temporary communication issues.
  
  Related Information:
  
  SAP Notes: Check for any relevant SAP Notes that may address known issues or provide patches related to MFS and PLC communication.
  Documentation: Review the SAP EWM and MFS documentation for detailed configuration steps and troubleshooting guidelines.
  Support: If the issue persists, consider reaching out to SAP support or your system administrator for further assistance.
  
  By following these steps, you should be able to diagnose and resolve the communication issue between SAP EWM and the PLC.