FIRE ALARM DEVICE Russian patent published in 1995 - IPC

FIELD: technical physics. SUBSTANCE: fire alarm device includes n channels, each carrying temperature-sensitive element 1 (1.1-1.n). One lead of it is connected to one lead of check resistor 3 (3.1-1.n) through signal-actuated relay 2 and to proper (from 1 to n) immobile contact of first switch 4. Other lead of temperature-sensitive element 1 is coupled through adjustment resistor to other lead of check resistor 3 and to proper (from 1 to n) immobile contact of second switch 5. Mobile contacts of first 4 and second 5 switches are coupled kinematically and linked to supply wire through voltage dividers. Mobile elements of make contacts of signal-actuated relays of all channels are tied up together and are connected to one supply wire and immobile elements of make contacts of signal-actuated relays 9 (9.1-9. n) are linked through windings of check relay to other supply wire. One group of make contacts of check relay is connected through first signal-actuated element to supply wires in parallel to each other. Their number is equal to n. Make contacts of other group of all check relays are connected in series and are linked through second signal-actuated element to supply wires. Two leads are interconnected in series with check resistors of all channels and are coupled to additional immobile contacts in first and second switches. EFFECT: reduced time of test of system. 1 dwg