ACTUATOR FOR UNDER-VOLTAGE AND SHUNT RELEASE IN MOULDED CASE CIRCUIT BREAKER

摘要

The disclosure relates to an under voltage / shunt release incorporated with MCCBs. In an embodiment, the under voltage and shunt release incorporates an improved cam based actuator configured to provide adequate over travel before crossing OFF position of knob of the circuit breaker during resetting operation. This ensure that the under voltage / shunt release does not remain de-latched when the breaker knob has returned to OFF position after the resetting operation and actuation command is received by the release. In another aspect, ensuring enough over travel before crossing the OFF position can prevent midway tripping of circuit breaker during shifting of circuit breaker knob to ON position due to de-latched under voltage / shunt release even when actuating command has gone off before switching ON the breaker.