Power-off protection method and device of low-voltage circuit breaker and low-voltage circuit breaker

The invention belongs to the technical field of low-voltage circuit breakers, and particularly relates to a power-off protection method and device for a low-voltage circuit breaker and the low-voltage circuit breaker.The power-off protection method comprises the following steps that S1, when overload or short circuit occurs in a circuit, the current in the circuit is increased and exceeds a preset value, and the end of a transverse rod is jacked through a bimetallic strip or an electromagnetic release; s2, after one end of the cross rod is jacked, the cross rod rotates, the other end of the cross rod jacks the operating mechanism to trip, the moving contact and the static contact are driven to be separated, and a circuit is disconnected; and S3, after the cross rod pushes the operating mechanism to trip and disconnect the circuit, a circuit break prompt mechanism is used for reminding that power failure is an overload condition or a short circuit condition, the direction of tripping power failure can be preli