a circuit breaker operating mechanism employs a multi - latch arrangement for controlling the automatic opening of the circuit breaker contacts upon predetermined overcurrent conditions . the multi - latch assembly is robotically assembled to the operating mechanism and is retained thereon by means of a retainer tab . the circuit breaker case and cover contain integrally formed steps which receive extensions formed on the operating mechanism assembly . the operating mechanism assembly becomes wedged between the circuit breaker cover and case when the cover is later fastened to the case .