For single phase or three phase circuit breakers. Through a small supervision current the whole circuit is supervised, in both positions of the circuit breaker (open or closed).

The correct state of the circuit is showed with a green LED on the front plate of the relay. The output contacts change their position if the relay detects a failure in the continuity of the circuit.

The single phase trip circuit supervision relay can be manufactured with different LED indicator configurations, refers to selection chart for more detailed information