Security is primary concern everywhere and for every one. Every person wants his home, industry etc. to be secured. This project describes a security alarm system that can monitor an industry and home. This is a simple and useful security system and easy to install. This fire / smoke detector is realized using readily available, low cost components. One of its many applications is in any offices and shops for security against fire. The detector will sense smoke caused by fire accident and switch on the water sprinkler to prevent major damage.


In this project we are using AT89S52 MCU, Fire sensor, Water sprinkler, relay driver. If any fire accident occurs, the fire sensor senses the raise in temperature and it sends signal to microcontroller. As a result, relay is turned ON. This, in turn, energizes relay. The relay contacts can be used to switch on the device to prevent major damage caused by fire. Automatically the water sprinkler gets on. Actually in this project we are using three fire sensors if any two fire sensors are detected then the water sprinkler will on. The status of the sensor will be displayed on the LCD Displayed.


This project used regulated 5V, 500mA power supply. 7805 three terminal voltage regulator is used for voltage regulation. Bridge type full wave rectifier is used to rectify the ac out put of secondary of 230/12V step down transformer.


Block diagram: 

7 (2)



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