SECURITY ALARM SYSTEM Russian patent published in 1997 - IPC

FIELD: radio engineering, in particular, protection against house breaking, fire, gas leakage and other emergency situations. SUBSTANCE: device has microprocessor unit and several user sets which are located in separate monitored objects. Each user set has control unit, multiplexer, demultiplexer, detectors and flip-flops for connection of detectors to input of multiplexer, serial circuit of code lock, detector of its state, OR gate, which other inputs are connected to separate outputs of said flip-flops, special flip-flop, which has gate output and which gate input is connected to output of control unit. In addition device has OR gate, which second input is connected to output of multiplexer and indicator unit which is connected to output of multiplexer and OR gate. This results in possibility to identify type of fired protection function, to specify time periods for monitoring objects and to provide information exchange between monitored objects and central station through two-wire communication line. EFFECT: increased adaptive possibilities with respect to number of monitored objects, number of detectors and their functional variation. 2 cl, 6 dwg, 1 tbl