Zone Alarm System


Posted on Feb 5, 2014

At switch on, C6 will charge via R11, this acts as the exit delay and is set to around 30 seconds. This can be altered by varying either C6 or R11. Once the timing period has elapsed, LED6 will light, meaning the system is armed. LED6 may be mounted externally (at the bell box for example) and provides visual indication that the system has set. On


Zone Alarm System
Click here to download the full size of the above Circuit.

ce set any contact that opens will trigger the alarm, including Zone 1. To prevent triggering the alarm on entry to the building, the concealed re-entry switch must be operated. This will discharge C6 and start the entry timer. The re-entry switch could be a concealed reed switch, located anywhere in a door frame, but invisible to the eye. The panic switch, when pressed, will trigger the alarm when set. Relay contacts RLA1 provide the latch, RLA2 operate the siren or buzzer.




Leave Comment

characters left:

Related Circuits

  • New Circuits

    .

     


    Popular Circuits

    Ice warning alarm 12V
    ISP Programming Kit for AT89S52 and AVR series Microcontroller
    12V 60A car battery
    Reading and writing Atmega168 EEPROM Tutorial
    REMOTE TELEPHONE BELL RINGER
    Expansion - C64 to 256kB
    Discrete circuit elements constituting the ultrasonic transmitter
    Step-up switching power supply circuit diagram



    Top