ALARM SIGNAL SYSTEM Russian patent published in 1995 - IPC

FIELD: alarm signalling. SUBSTANCE: system comprises two differential chains having changing connection with elements of the device as compared with the prototype. EFFECT: higher stability of the analysis time, periodical confirmation of the initial state of flip-flops, blocking of the device for the time of transition processes and a difference of alarm signals about trespassing, and warning about short-term failure of supply voltage. 3 dwg