ES445347A1 - Multi-pole circuit breaker with adjustable thermal trip unit - Google Patents

Abstract

Improvements introduced in a multi-pole circuit breaker that includes cooperable contacts at each pole, an actuation mechanism that includes a lockable member that, when released from its retention position, causes the automatic operation of the actuation mechanism causing the simultaneous opening of the contacts at all poles, and a device that trips it to effect the release of said lockable member when an abnormal current state takes place at any pole, said trip device comprising a trip bar structure supported for trip movement thereof. which results in the release of said lockable member, and current responsive means comprising bimetal elements each of which is associated with one of the poles of the circuit breaker and arranged in predetermined clearance relationship with the trip bar structure in order to apply to the last yr performing said trip movement thereof when the bimetal element responds to a predetermined overload current that circulates in the associated pole, characterized in that said trip bar structure comprises a main trip bar supported to carry out said trip movement, and an auxiliary trigger bar arranged on the main trigger bar to move simultaneously with it, the bimetallic elements cooperating with said auxiliary trigger bar, and the last one being adjustable in relation to the main trigger bar in such a way that the separation between the auxiliary firing bar and the bimetal elements cooperating with it, and adjustment members supported on one of said main and auxiliary firing bars and cooperating with the other in order to adjust the auxiliary firing bar. said mode when the adjustment means are actuated. (Machine-translation by Google Translate, not legally binding)