Tuesday, May 9, 2017
A circuit breaker is more reliable for tripping big machines than a drive. Hence some engineers prefer tripping a machine from the breaker via the PLC/safety controller. The machine could be pump or compressor.
After the trip, the startup means energizing the primary side of the transformer, whose secondary side is connected to the variable frequency drive. This subjects the transformer to the startup inrush current which could degrade it.
Tripping the machine may be due ...