capacitance alarm

capacitance alarm

A device which is electrically connected to a protected metal enclosure (such as a safe, vault, file, or security cabinet) so that the enclosure itself becomes part of a balanced-capacitance circuit. A person approaching the protected cabinet unbalances the electrical circuit and activates a security alarm.
References in periodicals archive ?
Offices in which highly sensitive business takes place, such as the district attorney's office and court record rooms, should be protected by CCTV cameras, door contact switches, and motion detectors within the room or, at the least, capacitance alarms on the file cabinet safes.