Ground fault circuit breaker with flat bus bars for sensing coils, insulating barriers and test contacts

摘要

A ground fault circuit breaker (1) has line and neutral bus bars (101, 103) extending through the center apertures (105, 107) of two laterally spaced toroidal coils (97, 99) to form the primaries of ground fault sensing transformers. The bus bars (101, 103) have flat center sections (101a, 103a) extending between the two coils (97, 99) parallel to the coil end faces and offset laterally by flat laterally extending legs (101b, 101c, 103b, 103c) at each end which are bent transverse to the end faces of the coils and extend through the coil apertures (105, 107) in flat confronting relation. The leg (103c) on one end of the neutral bus bar (103) has a terminal portion (103c') bent into a plane parallel to the center section with a crimp (103d) at the end for attachment to a neutral pigtail (11). Also provided are insulating barriers (235, 237) for flat, confronting C-shaped bus bars (101, 103) with facing, depending end portions (101b, 101c, 103b, 103c) are integrally formed with a pair of confronting C-shaped insulating members (237, 239, 263, 265) conforming to the shape of the bus bars and joined by a pair of projections (253, 259, 261) extending between and electrically insulating the facing, depending end portions from each other. Both the fixed and movable contacts (135, 137) of the ground fault test switch (17) are directly secured to the printed circuit board (31) on which the ground fault detection circuit (119) is implemented, with the movable contact (137) also providing the spring bias for the test button (139).