Posted by: Ghulam Abbas
Posted on: 26 October 2014
The main objective of this project will indicate and detect any presence of smoke and fire in its surrounding environment. For smoke indication, the main idea is to use the voltage across a LDR (light dependent resistance) as an input to activate a transistor/switch to turn on the indicator
However, for fire indication, negative type thermistor have been used whose resistance decreases with the increase in temperature, so after the resistance has decreased, more current will flow that will be used some how to activate a switch which turns on the indicator/buzzer for fire detection.