Our application sometimes misses the PLC's brief request for inspection-cycle coordination.
I'm reviewing that ordinary, non-safety handshake for Universal Robots UR5e in a sample-checking cell with separate safety controls, with a fixture-mounted bracket in the setup.
Signal ownership and clearing conditions aren't clearly documented.
The safety functions are independently engineered and separate from this job interface.
I've compared the trace: the PLC raises and clears the request between consecutive application polls, with no observed acknowledgement before it clears.
Take an ownership table and a retained-request proposal to the interface owner. A request held until matching acknowledgement should settle the handshake in an offline review.
@GabrielAbbott0018 Yes, I overstated that. Retention addresses the missed pulse. The offline review also needs matching identity, reset ownership and restart cases before the design is complete.