Our application sometimes misses the PLC's brief request for part inspection.
I'm reviewing that ordinary, non-safety handshake for Universal Robots UR5e in a workshop inspection station awaiting commissioning, with an inspection coupon in the setup.
Signal ownership and clearing conditions aren't clearly documented.
The safety functions are independently engineered and separate from this job interface.
@MinaBaker0511 I've compared the trace: the PLC raises and clears the request between consecutive application polls, with no observed acknowledgement before it clears.
@YasminBrown0876 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.
Holding the request addresses the missed pulse, but it doesn't settle the interface. A retained request needs identity and restart rules to avoid being mistaken for new work.
You're right; my conclusion skipped necessary cases. Retaining the request addresses visibility, while identity, clearing ownership and restart behaviour must also be reviewed.
@MinaBaker0511 Should I record readers as well as the single writer? Our existing phrase used by PLC doesn't distinguish setting, reading or clearing a field.