• Y LAVANYA
• Ch B K Rajeswari

A magnetic door alarm for use in conjunction with normally unlocked emergency exit doors of a type in which a buzzer is produced when the door is opened. The device includes the Hall Effect sensor, 7805 voltage regulator, bar magnet and IC 555 timer. These components are normally housed on an inner surface of the door. One end of the circuit is mounted on the door and on the other end a large magnet is placed. Where, polarity of the magnet is opposite to the Hall Effect sensor in the circuit. So that whenever the door is opened, Buzzer can produce sound and LED is ON. When door is closed Buzzer will not produce sound because magnet is very close to the Hall Effect sensor. Based on the Magnetic effect towards the Hall Effect sensor the buzzer produces sound.

Buzzer, Hall Effect Sensor, 7805 Voltage Regulator, IC555 Timer, Magnet.

"Door Alarm using Hall Effect Sensor", International Journal of Emerging Technologies and Innovative Research (www.jetir.org), ISSN:2349-5162, Vol.6, Issue 6, page no.190-192, June 2019, Available :http://www.jetir.org/papers/JETIR1908029.pdf

"Door Alarm using Hall Effect Sensor", International Journal of Emerging Technologies and Innovative Research (www.jetir.org | UGC and issn Approved), ISSN:2349-5162, Vol.6, Issue 6, page no. pp190-192, June 2019, Available at : http://www.jetir.org/papers/JETIR1908029.pdf