Sequential resetting circuit interrupter

Abstract

A circuit interrupter to trip on occurrence of ground faults or the like in which the neutral and electrified contacts are mounted to open and close in a pre-determined sequence when being reset. When closing to reset the mechanism, the neutral contacts make first and the 'hot' or electrified contacts can only make after the neutral contacts have closed. On pushing the reset button to open, the converse is true. The hot or electrified contacts break first and the neutral contacts can break only after the electrified contacts have separated and interrupted the hot conductor. This sequential operation protects the circuit from an inadvertent making of the hot contacts while the neutral contacts were still open. Under such condition, the circuit would be electrified but there would be no ground fault protection. The ground fault interrupter would not be powered as long as the neutral contacts remain open. A resistor is connected between the ground terminal and the neutral conductor on the load side of the breaker to protect against cross wiring the line conductors to the ground fault interrupter terminals. If the hot or electrified line conductor is mistakenly cross-wired to the neutral terminal of the ground fault interrupter, the resistive connection between neutral and ground simulates a ground fault condition and causes the mechanism to trip. It cannot be reset as long as the hot wire is connected to the neutral terminal of the interrupter.