It is very useful project for factory godowns, gas godowns and other places where there a possiblities of fire.
Step 1: COMPONENTS
2. GSM/GPRS Modem 800H or 900A
3. IR sensor with analog output
4. Patch cords
Step 2: Connections
GSM modem required large amount of current so use 12v 1amp power supply for it. In my case I used four 9v batteries connected in parallel. Now Connect the vcc pin of ir sensor to 5v of the arduino, connect gnd to gnd of arduino and Analog out pin of sensor to the A0 of the arduino.
Connect your pc to the arduino Upload the program usin ARDUINO IDE. Note that program must be uploaded before connecting GSM modem, because modem may get damage.
After Uploading program to arduino connect the Rx of modem to Tx of Arduino, Tx of modem to Rx of arduino & Ground to ground.
You can see in circuit diagram.