ELECTRICAL SWITCHING APPARATUS, CIRCUIT INTERRUPTER AND METHOD OF INTERRUPTING OVERCURRENTS OF A POWER CIRCUIT

摘要

A circuit interrupter (1) includes a housing (112), separable contacts (170,172), and an operating mechanism (19) including a latch (20). The operating mechanism opens the contacts responsive to actuation of the latch. A trip mechanism (27) cooperates with the latch to trip open the contacts. The trip mechanism includes a thermal overload mechanism (184,190) actuating the latch responsive to a thermal fault caused by current flowing through the contacts, a solenoid (98) cooperating with the thermal overload mechanism to actuate the latch responsive to the electromagnetic device being energized, and a processor (55) repetitively determining (202) a value of the current flowing through the contacts, determining (204,208) if the value exceeds a predetermined value (K1) for a number of occurrences, and responsively energizing (208,210) the solenoid, in order to actuate the latch contemporaneous with actuation of the latch by the thermal overload mechanism, in order to decrease the time to trip open the contacts