Introduction: Arduino LPG and Flame Detector

This project is an Arduino based LPG and Flame detector. I got the idea to build this project because these days I've got my vacation and I've always wanted to make an innovative and unique project.Hope you'll like it.

Step 1: Collecting the Necessary Parts...

  1. Arduino UNO
  2. Toggle switch
  3. 12v buzzer
  4. MQ2 LPG sensor
  5. Flame sensor
  6. Relay Connectivity (
  7. Red LEDs (2)
  8. Green LEDs (2)
  9. Acrylic Sheet
  10. 9v battery or 7.4v (two 18650 batteries in series)
  11. 2mm Acrylic sheet
  12. Jumper wires (Female to Male)

Extra Tools:

  • Pen Knife (to cut Acrylic)
  • Ruler
  • Drill
  • Grinding machine

Step 2: ​Constructing the Acrylic Box...

Take the acrylic sheet and cut the following sizes

  • 10.2cm x 10.2cm 1Pc
  • 10cm x 10cm 1Pc
  • 10cm x 4cm 2Pcs
  • 10.5cm x 4 cm 2Pcs

Allign all the pieces exept the (10.2cm x 10.2cm) piece into a square shaped box and glue it using either superglue or suing hot glue.

It should look something like the pic above

Step 3: Connections to the Arduino

Initially we haev to connect the MQ2 Sensor to the board by connecting:

  • the VCC pin to the 5v pin of the Arduino
  • the GND pin to the GND pin of the Arduino
  • the AO pin to the A0 pin of the Arduino

Next the Flame Sensor:

  • the VCC pin to the 5v pin of the Arduino
  • the GND pin to the GND pin of the Arduino
  • the DO pin to the digital pin 2 of the Arduino

Next the relay connection.I have used the same relay for both the sensor output Buzzer.Therefore i used two separate digital pins for the same relay connectivity by soldering two wires to the same circuit board as in the picture which is shown above.

Next is connecting the LEDs. I connected two RED LEDs to digital pin 2 and digital pin 12,the one on digital pin 2 being the output for the flame sensor and the one on the digital pin 12 being the output for the LPG sensor.

Step 4: Preparing the Acrylic Box for the Project to Fit In...

Initially i drilled two holes for the two RED LEDs and a small hole to add the buzzer wires.

Next up i drilled a large hole to add the LPG sensor and glued it up using hot glue and a small led size hole for the flame sensor's LED.

Finally i sanded the edges of the acrylic box and if you'll have an acrylic buffer machine you'll could use it to polish out the edges to have a well polished finish!!!

Step 5: Coding...

The code has been uploaded below. Upload the code and power on the project and check it!!

This code is entirely my work you'll can edit it if you'll want.

Step 6: Other Connections...

Moreover i added the DC jack to the project to charge my (18650 LI-ion) batteries. Afterwards i added a toggle switch in between the positive wire for the power supply of the arduino so that the toggle switch powers on and off the system!

Hope this project helped you'll and i hope you would give me a "like or rather favorite"

Thank you guys!!

Arduino All The Things! Contest

Participated in the
Arduino All The Things! Contest

Tech Contest

Participated in the
Tech Contest