The auxiliary contact can indicate the status of the circuit breaker when the circuit breaker is switched on/off. It is mainly used for the display of the circuit breaker’s status, and control other related electrical appliances by the status of the circuit breaker.For example, it can output signals to signal lights, relays and logical circuits, etc.
The under-voltage release is a protective accessory. When the supply voltage is 35%～70% lower than the rated voltage of the release, it can trip the circuit breaker; when the supply voltage is 35% lower than its rated voltage, it can ensure that the circuit breaker does not close. When the supply voltage is 85% higher thanits rated voltage, it can ensure the circuit breaker works normally.
When there is a trip due to a fault such as overload, short circuit or under voltage, it can send out a signal. The alarm contact determines whether the circuit breaker is on the tripping state or the on/off state through the position of the device itself, thenthe fault signal will be output through an external alarm device, a signal light, or other electrical signals.
The shunt release is essentially a coil and a tripper. When the specified voltage is applied to the shunt coil, the circuit breaker will trip and close. It is often used in the control of long-distance automatic power-off. Now it is most used to cut off the non-fire power supply in the fire control room.