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Safety Semantic Error: Feedback not allowed.

Invalid explicit feedback detected in an SNOLD worksheet.

Remedy:
  1. Double-click the error in the Error List to jump to the suspected worksheet (where the feedback is marked).
  2. Remove the feedback logic by modifying the code.
    Split the invalid network into two separate networks and use a feedback variable to program an allowed implicit feedback.
    Refer to the topic "Implicit Feedbacks in SNOLD" for details and an example.

    Observe the warning below.

WARNING
Unintended machine operation
  • Verify the impact of programmed implicit feedbacks particularly with respect to the possibly different timing and to their effect on the performance of your application.
  • Make certain that suitable organizational measures (according to applicable sector standards) have been taken to avoid hazardous situations if the safety-related logic application operates in an unintended or incorrect way.
  • Do not enter the zone of operation while the machine is operating.
  • Ensure that no other persons can access the zone of operation while the machine is operating.
  • Observe the regulations given by relevant sector standards while the machine is running in any other operating mode than "operational".
  • Use appropriate safety interlocks where personnel and/or equipment hazards exist.