Interlock Switch

An item which completes or interrupts the connections in one or more electrical circuits. Its electrical elements consist of separate parts designed to be mounted respectively on a frame and a door, drawer, or cover, it acts as a safety device to open a circuit when the door or drawer is opened or the cover removed. It does not include devices of which a complete switch with an actuator is one of the parts; for such devices, use switch (as modified). Excludes switch, mercury; and switch, reed.