摘要 |
A molded case circuit breaker includes a manually resettable undervoltage trip mechanism for initiating a trip operation of the circuit breaker upon an undervoltage condition. The undervoltage trip mechanism includes a solenoid having a fixed electrical coil surrounding a pair of separable movable ferromagnetic plungers. Disposed between and captured by the two plungers is a compression spring for physically separating the two plungers upon the occurrence of an undervoltage condition. Upon such an undervoltage condition, one of the plungers is positioned to engage and rotate a trip lever for initiating a trip operation of the circuit breaker. The other plunger is secured to an elongated manually depressible reset button that extends through the molded case of the circuit breaker. After a trip operation, the reset button can be depressed to reestablish physical engagement between the first and second plungers, enabling the circuit breaker to be reset.
|