Published January 10, 2023

Gas Leakage Detector

How to use MQ2 Gas Sensor

BeginnerProtip3,234

Things used in this project

Hardware components

Seeed Studio Grove - Gas Sensor(MQ2)

Breadboard (generic)

LED (generic)

Jumper wires (generic)

Arduino

Software apps and online services

Arduino IDE

Story

Hey Guys, In this tutorial I'm going to show you How to use the MQ2 Gas Sensor in an easy way.

The MQ-2 is a smoke and combustible gas sensor. It can detect flammable gas in a range of 300 - 10000ppm. Its most common use is domestic gas leakage alarms and detectors with a high sensitivity to propane and smoke. This type of smoke sensor is made of a tin oxide semiconductor gas sensing material.

Full Video tutorial

Code

Project Code

int red_led=13;//indicates gas
int green_led=12;//indicates normal
int smokeA0 = A0;//indicates sensor is connected to A5
int sensorThres=400;//The threshold value

void setup()
{
pinMode(red_led,OUTPUT);//red led as output
pinMode(green_led,OUTPUT);//green led as output
pinMode(A0,INPUT);//sensor as input
Serial.begin(9600);//starts the code
}
void loop()//loops
{
int gas_avalue=analogRead(smokeA0);//reads sensor value
if (gas_avalue > sensorThres)//sees if it reached threshold value
{
digitalWrite(red_led, HIGH);//turns on red led
digitalWrite(green_led, LOW);//turns off green led

}
else//if it hasn't reached threshold value
{
digitalWrite(red_led, LOW);//turns red led off
digitalWrite(green_led, HIGH);//turn green led on

}
delay(100);//delay 0.1 sec
}