Abstract: An interlock switch arrangement is used to disconnect the low voltage connections of electrical components such as transformers and the like in metal-enclosed switchgear. An electrical switch is mounted within a switch housing positioned and mounted adjacent to the access opening of the metal enclosure of the switchgear. A key projection or finger is mounted on a door overlying the access opening to the enclosure and positioned to enter an opening in the switch housing when the door is closed and to actuate the switch so that an electrical circuit is completed for electrical components within the enclosure. When the door is opened, the key projection disengages the switch causing the switch to open thereby electrically disconnecting the components so that a serviceman can perform maintenance with improved security against electrical shock. Typically, the invention is used on metal-enclosed switchgear having a double-door arrangement, i.e.