GB1472505A - Remote sensing and/or control system - Google Patents

Abstract

1472505 Selective signalling DAMON CORP 18 July 1975 30173/75 Heading G4H A central station 9 addresses a plurality of remote stations 40, 40<SP>1</SP> ... by generating wave signals on a plurality of wires going to the remote stations (the wave length increasing by a whole multiple going from wire to wire), to permit data transfer in respective time slots, each remote station, e.g. 40 recognizing its address by means including inverters, e.g. 50-53. In Fig. 1, a clock-driven binary counter 14 addresses the remote stations 40 &c. on common lines A, B, C, D, each remote station having a pair of jumpers e.g. 41, 42 per line to connect it directly or via an inverter to an AND gate, e.g. 54 which sends the state of a sensing switch, e.g. 57 to the central station over a line 60 to be gated into a respective one of flip-flops F under control of a decoder 16 driven by the counter 14. The flip-flops F control respective lamps L. The counter 14 also controls a multiplexer 65 to scan control switches 70 to control devices, e.g. 75 at the remote stations over a line 71. Some of the flip-flops F may control some of the switches 70, so that some remote stations control others. In a modification, the sensing switches are single-pole, double-throw switches, each replacing a pair of the jumpers, so that each remote station has two addresses for monitoring respective states of the sensing switch, and there are correspondingly two lamps at the central station per sensing switch. The system may be used in a building, for fire protection &c.