Low-voltage protective switch with bimetallic overcurrent trip - whose length is adjustable for variation of current rating at which sliding switch is opened abruptly

摘要

The bimetallic element (1) has one end welded to a carriage (2) cantilevered to a platform (4). The other end protrudes through a window in a slider (3) movable between two positions. In one position the switch is not tripped, and in the other position the deformation of the element (1) by differential thermal expansion opens the switch contacts. The rating can be adjusted by means of a screw (16) which raises and lowers the carriage (2) w.r.t. the platform (4). ADVANTAGE - Range of overcurrent ratings is extended by variability of active length of bimetallic element.