How to Use MQ2 Gas Sensor - Arduino Tutorial

245,443

249

52

Introduction: How to Use MQ2 Gas Sensor - Arduino Tutorial

About: Arduino Tutorials by Codebender.cc Team

The MQ series of gas sensors use a small heater inside with an electro-chemical sensor. They are sensitive for a range of gasses and are used indoors at room temperature. The output is an analog signal and can be read with an analog input of the Arduino.

The MQ-2 Gas Sensor module is useful for gas leakage detecting in home and industry. It can detect LPG, i-butane, propane, methane ,alcohol, hydrogen and smoke.

Some modules have a built-in variable resistor to adjust the sensitivity of the sensor.

Note: The sensor becomes very hot after a while, don't touch it!

In this tutorial we will use the serial monitor of Codebender (or Arduino IDE) to see how the sensor acts in variable gasses.

So, let's get started!

Step 1: What You Will Need

For this tutorial you will need:

  • Arduino uno
  • Breadboard
  • MQ-2 Gas sensor module

Step 2: The Circuit

The connections are pretty easy:

  • Vcc to Arduino 5V pin
  • GNG to Arduino GND pin
  • Output to Arduino Analog A0 pin

Note: The sensor becomes very hot after a while, don't touch it!

Step 3: The Code

Here's the code, embedded using Codebender!

Try downloading the codebender plugin and clicking on the Run on Arduino button to program your Arduino with this sketch. And that's it, you've programmed your Arduino board! Press connect button to start serial communication with your Arduino board.

Now you can try this:

Take a lighter and press the button to release gas near the sensor. Observe values on serial monitor.

You can keep playing with that by clicking the "Edit" button and start making your own modifications to the code.

Step 4: Well Done!

You have successfully completed one more Arduino "How to" tutorial and you learned how to use the MQ-2 Gas sensor with Arduino.

Tip: You can use this tutorial to read values from all MQ gas sensors (MQ-2, MQ-3, MQ-4, MQ-5, MQ-6, MQ-7, etc)

I hope you liked this, let me know in the comments.
There will be more of them, so make sure to click Follow button!

6 People Made This Project!

Recommendations

  • Make it Glow Contest

    Make it Glow Contest
  • First Time Author Contest

    First Time Author Contest
  • PCB Challenge

    PCB Challenge

52 Discussions

0
TarekS30
TarekS30

3 years ago

Can i supply this sensor with a 9V battery?

0
Mickey The Maker
Mickey The Maker

Reply 10 months ago

You can supply the adrinio with a 9V battery.

0
nishanthgadam
nishanthgadam

1 year ago

Thanks for sharing this article nice info
gas transmitters

0
HanNaKim02
HanNaKim02

Question 1 year ago

does we need to combine the lcd coding with this MQ-2 coding to get the value of smoke? or it just appear on lcd when we set it up on the breadboard?

0
Ankitp1995
Ankitp1995

Question 1 year ago on Step 4

i have MQ2 and MQ 4 sensor and arduino uno, i want to check methane composition in biogas. i want codes please help me

0
LukasS8
LukasS8

5 years ago on Introduction

Hey could one arduino power all MQ Sensors (MQ-2,3,4,5,6,7..) or would it need to much current?

0
codebender_cc
codebender_cc

Reply 5 years ago on Introduction

I don't know... maybe you will need an external power source.

0
JAK101
JAK101

Reply 4 years ago

You can only use an external power source to power the digital IO pins. External power for analog is not recommended due to noise issues.

0
ChoudharyA2
ChoudharyA2

Reply 3 years ago

Noise Issue?? Can you explain

0
TheMake
TheMake

Reply 5 years ago

maybe you could us a voltage regulator or same what you said...... :)

0
JAK101
JAK101

Reply 4 years ago

Your best bet is to buy a sensor shield and use it with your Uno or Mega (I prefer the mega because there are more IO pins). However, you should note that no matter which board you choose it can only supply so much current to each sensor. You reach a point where you run out. Adding an external power supply doesn't work either with the sensor shields. External power isn't applied to the analog pins due to noise issues. Basically, you are limited on the amounts of analog sensors you can use.

0
TheMake
TheMake

Reply 5 years ago

it could power any of these with 5v

0
TheMake
TheMake

Reply 5 years ago

it could power any of these with 5v

0
itnas19
itnas19

3 years ago

Thanks very much, I've enjoy a lot making it.

From Madrid, Spain

0
SWETHAC2
SWETHAC2

3 years ago

How to use MQ2 sensor as alcohol detector?please give me tutorial

0
KutsalÖ
KutsalÖ

4 years ago

hi. Can I use arduino nano. Please help me.

0
diy_bloke
diy_bloke

Reply 4 years ago

yes can

0
KutsalÖ
KutsalÖ

Reply 3 years ago

thanks