Faulty detector detection method for centralized alarm system e.g. fire alarm system, uses current-modulated data supplied by interrogated detectors to central evaluation point with controlled switch opening for fault location

摘要

The faulty detector detection method determines the voltage drop across a measuring resistance (Rm1,Rm2) associated with each detector (M1,M2), which is inserted in one of the line wires (L1) linking the detectors to a central evaluation point, via cyclic voltage-modulated control and interrogation data provided by the latter. The current-modulated data provided by the interrogated detectors is received by the central evaluation point for closing the switches of all detectors when a fault is indicated, with storage of the detector current values and controlled opening of the switches for the successive detectors until the faulty detector is located. Also included are Independent claims for the following: (a) a faulty alarm system detector detection circuit; (b) and a method for separation of a faulty detector from an alarm system.