Magnetic circuit breakers operate via a solenoid, and trip nearly instantly as soon as the threshold current has been reached. This type is appropriate for printed circuit board application and impluse disconnection in control applications. Often a magnetic circuit breaker is combined with a hydraulic delay to make it tolerant for current surges. Preferably, the circuit breaker is mounted in a horizontal position to prevent gravity from influencing the movement of solenoid. If mounted in a non-horizontal position, derating may be needed.