SE9504260D0 - Detector - Google Patents

Abstract

The present invention relates to a controlling and/or registering system (A) to which different types of detectors (1) can be connected and adapted so that a satellite unit belonging to the system is able to detect the removal of a detector (1) from a supportive surface (1') or an attempt to remove the detector from the supportive surface, or to detect disconnection of a detector from the system (A). Respective detectors include an alarm element (2) having on one side (2') thereof an adhesive material (21) by means of which the detector can be affixed to the supportive surface (1'), and a connection cable (3) which extends from the alarm element (2) and connects with the satellite unit. At least one of the detectors includes an identification circuit (4) that has a unique identity. An electrically conductive loop (3') extends from the satellite unit and continues through a first conductor (3a) within the connection cable (3) and connects with the identification circuit (4) through the medium of means within the alarm element (2), and continues from the identification circuit (4) to a second conductor (3b) within the connection cable (3), whereafter the loop (3') returns to the satellite unit via the second conductor (3b). The satellite unit is able to read the identity of the identification circuit through the medium of the loop (3') and the means is adapted to short-circuit the loop (3') "upstream" of the identification circuit (4) and/or break the loop (3') upon removal of the detector (1) from the supportive surface or when an attempt is made to remove the detector (1) from the supportive surface, such as to interrupt the ability of the satellite unit to read the identity.