Arduino Fire Alarm 1.0[edit | edit source]

Fast detection, annoying alarm, saves your expensive toys from unexpected combustion!

Parts List[edit | edit source]

Arduino Development Board (NG, Duemilanove, Diecimila... others can be used as well with some effort)
Hamamatsu Photonics UV TRON Flame Sensor and driver circuit (sold separately, or as a kit)
Radio Shack 102dB Piezo Siren (About $6 USD) RS Model # 273-079, self contained modulator.
LED and associated current limiting resistor (you choose! You have 5 volts and some number of mA to play)
Power supply with at least 9v but no more than 14 volts and a barrel connector that fits the Arduino.
Perf board for soldering parts cleanly, or a breadboard.
Simple transistor, three legged variety, used for controlling the 150 mA siren current
Some wire to connect the sensor assembly to the perf board.

Schematic forthcoming...

Download the Arduino Sketch here: Arduino_Fire_Alarm_v1_0.pde

The field of view of the sensor is wide, but not omnidirectional. Keep this in mind when you are positioning the sensor tube for an area of coverage.
In our current Lazzzor installation, the work table blocks the sensor much of the time. The sensor will not likely be triggered unless a really large fire erupts. This isn't good enough, and so there will be a redesign of the sensor assembly to bring the tube above the work table. The distance between the driver board and the tube must be short, making this a challenging effort.
The glass lid on the Lazzzor blocks the UV light emitted by flames, making it impossible to use the sensor externally with the lid closed.

Add Twitter support via an Ethershield... Not super practical, but novel.
Add a defeat switch w/timer in case of multiple false alarms. The defeat function would time out to prevent negligent disabling of the alarm.
Using the Ethershield, implement an SNMP-like event trap scheme. This should allow the sensor to integrate into a larger alarm system.