1.The CB one or two Poles are fail to open or close the PD stage-I operate and open the breaker. If CB dose not open PD stage II will operate.Now PD stage-I trip command should reset.Otherwise The trip command continuously going to Trip Coil.
2.We can reset the PD stage-I relay in two ways 1.The PD stage-II contact can add serious with PD stage-I tripping circuit or serious with timer +ve. 2.PD stage-I Timer should be on delay pulse generator and it will give one pulse to PD stage-I tripping relay and not continuous pick-up command.
3.This method can be use in BF circuit also.
