Patent ID: 8643451

Claim:
A circuit breaker, comprising: a yoke configured to form a magnetic field path; a trip coil mounted to the yoke and directly connected to a secondary winding of a ZCT (Zero-phase Current Transformer); a lever arranged at a first side of the yoke and configured to trip a mechanism of the circuit breaker; a spring a first end of which is connected to the lever and configured to provide a resistive force to the movement of the lever; a permanent magnet rotatably coupled to a second side of the yoke opposite the first side and configured to rotate in order to change a magnetic path direction of the permanent magnet to adjust a sensitivity current of the circuit breaker; a bracket mounted to the yoke opposite the trip coil wherein a first side of the bracket supports the lever; and wherein the permanent magnet is rotatably coupled to a lateral surface of the second side of the yoke and positioned such that an axis of rotation of the permanent magnet is substantially perpendicular to a longitudinal length of the lever when the lever is in a closed position.