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Smoke Detector Circuit - Fire Alarm

Topics: Security

An interesting electronic smoke detector circuit that can be used as a fire alarm.

Screenshot: Smoke Detector Circuit - Fire Alarm

This circuit uses a very simple approach to detecting smoke in the air. Quite simply, it uses a bulb as a light source, and an LDR (Light Dependent Resistor) as a light detector. As fire smoke comes between the bulb and LDR, the resistance of the LDR changes, which in turn trigger an alarm.

This probably isn't an ideal approach given that ambient light levels are likely to cause false alarms, however it is an interesting experiment. Just please don't set any fires while experimenting. And please don't rely on it as a replacement for a real fire alarm device.

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jsuresh3 says: (March 25 2008, 9:21am)

hello sir ... I am a hobbiest man .
I am very thankul to ur kind circuits thanks a lot.......

mmakhada says: (March 25 2008, 9:31am)

i would like to try to build this as my project for design projects.it seems as an interresting project.

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