Fire or intruder alarm system - using main unit socket and plug detector with alarm detector removal

摘要

The fire or intruder alarm uses three units, comprising a main unit (3) located in the surveillance area in a fixed position, a socket (2) and a detector unit (1), fitted to the main unit (3) via the socket (2). An alarm device (6) is positioned between the socket (2) and the detector (1), which is brought into operation when the detector (1) is fitted into the socket (2), and provides an acoustic alarm upon the removal of the detector (1) from the socket (2). All three units are secured together by releasable spring fastening means, with the socket (2) and/or the detector (3) pref. having to be removed from the surveillance location, before the detector (1) is removed from the socket (2). The socket (2) is pref. also connected to an external alarm circuit for indicating removal of the detector (1).