CIRCUIT BREAKER ARRANGEMENT FOR PROTECTION AGAINST ELECTRICAL ARCS

摘要

An arrangement in an electrical switching device for protection against electrical arcs comprises a tripping mechanism, a stationary contact carrier, a movable contact carrier, an exhaust vent, an arc runner, and an arc extinguishing barrier. The stationary contact carrier has a stationary contact mounted thereon, and the movable contact carrier has a movable contact mounted thereon. In response to an overcurrent condition, the tripping mechanism causes the movable contact carrier to rotate from a closed position to an open position, thereby generating an electrical arc. In the closed position the movable contact abuts the stationary contact, and in the open position the movable contact is separated from the stationary contact. The arc extinguishing barrier is composed of an outgassing material and is located between the stationary contact and a portion of the tripping mechanism. The stationary contact is located generally between the portion of the tripping mechanism and the arc runner such that the arc runner draws the electrical arc away from the portion of the tripping mechanism. The exhaust vent is located generally in line with the initial direction of movement of the movable contact when the movable contact carrier begins rotating from the closed position to the open position.