Molded case circuit breaker with arc suppressant features including magnetically permeable arc horn mounted on the contact arm

摘要

An electromagnetic circuit breaker is provided with a copper plated arc horn on the top side of the movable contact arm opposite the movable contact. The horn extends beyond the movable contact and has an upturned sweep so as to enhance migration of the electrical arc created upon opening of the contacts during a short circuit condition sensed by the breaker. An arc shoe is provided in conjunction with the fixed contact of the breaker as well and cooperates with the arc horn for the same purpose.