CAPACITIVE TYPE INTRUDER ALARM Russian patent published in 2007 - IPC G08B13/14 

FIELD: intruder alarms, possible use for protecting paintings, safes, displays, jewelry, statuettes, etc.

SUBSTANCE: capacitive type intruder alarm contains clock generator of periodic signal, made in form of individual module, to input of which sensitive element is connected. In case of influence of sensitive element, such as approach of a human to it, its electric capacity changes, and, therefore, frequency of periodic signal generated by generator changes, which fact is diagnosed by microcontroller. Device contains block for measuring capacity of sensitive element, for measuring grounding resistor, for automatic adjustment of sensitivity and for testing serviceability of the block, and signal output block, consisting of light signaling device and relay outputs for communication with receiving-controlling device.

EFFECT: increased interference resistance, expanded area of application.

4 cl, 1 dwg