| 摘要 |
PROBLEM TO BE SOLVED: To enhance reliability of a circuit breaker by preventing a bimetal from being impaired when a short circuit current flows through an electrical path, without connecting a current limit element or a parallel resistor, thereby stabilizing the operation.SOLUTION: The circuit breaker includes a bimetal trip device for operating a switching mechanism by displacing a bimetal thereby displacing a movable part when an overcurrent flows through the electrical path of the circuit breaker, and an electromagnetic trip device which operates the switching mechanism by displacement of a movable core, juxtaposed to the bimetal, with the electromagnetic force of a fixed core when a short circuit current flows through the electrical path thereby displacing the movable part. The bimetal is protected by such a configuration that a short circuit current flowing through the electrical path is shunted to the bimetal and the movable core. |
