Method for thermally calibrating circuit breaker trip mechanism and associated trip mechanism

摘要

A method for adjusting the calibration of a circuit breaker trip mechanism including a terminal element, a bimetal element connected thereto, and a trip bar. Laser energy is applied to lanced or pre-bent surfaces of the terminal element to thermally induce displacement thereof and thereby modify a trip distance between the bimetal element and the trip bar. Where a laser beam is directed to fall on a middle leg of a lanced or pre-bent section of the terminal element, the bimetal element moves in one direction relative to the trip bar. Conversely, where a laser beam is directed to fall on lateral legs of the lanced or pre-bent section of the terminal element, the bimetal element moves in an opposite direction relative to the trip bar. Thus, laser energy may be applied from the same direction, or to the same side of the trip structure, regardless of whether the trip time is to be increased or decreased. <IMAGE>