Arc chamber for electrical switchgear

The invention relates to an arc chamber (1) for electrical switchgear, in particular line protection circuit breakers, consisting of a contact arrangement having at least one stationary contact (3) and one moving contact (2), arc guiding devices (6, 7) and an arc splitter stack (9). A connecting terminal (14) having a connecting rail (12) is isolated from the arc chamber (1) by means of an insulating material wall (10). If an aperture (11) is arranged in the insulating material wall (10) such that an arc (20) which is struck in the arc chamber (1) attempts to find the direct path to the connecting rail (12), it is passed out of the area of the contacts (2 and 3) more quickly. In consequence, the errosion damage is kept as low as possible. This effect is further enhanced if a hole (13) is provided in the connecting rail (12), aligned with the aperture (11). Instead of one aperture (11) and one hole (13), a plurality of apertures (11') and a plurality of holes (13') can advantageously also be arranged in the insulating material wall (10) and in the connecting rail (12) (Fig. 1).