MQ2 Gas Sensor to Arduino

MQ2 Sensor is a gas module and it is suitable to detect Hydrogen, LPG, Smoke, CO, and Alcohol. It has high sensitivity and fast response time to measure and take the data.Sensitivity can be adjusted by potentiometer behind it

MQ2 Sensor Pin Configuration

Circuit

MQ2 Connections with Arduino

MQ2 Connections with Arduino and IIC LCD Display

Connections

Arduino MQ2

AO A0

5V VCC

GND GND

Code

#include <MQ2.h> #include <Wire.h> #include <LiquidCrystal_I2C.h> //I2C pins declaration LiquidCrystal_I2C lcd(0x27, 16,2); int Analog_Input = A0; int lpg, co, smoke; MQ2 mq2(Analog_Input); void setup(){ Serial.begin(9600); lcd.begin(); lcd.backlight(); mq2.begin(); } void loop(){ float* values= mq2.read(true); //set it false if you don't want to print the values in the Serial //lpg = values[0]; lpg = mq2.readLPG(); //co = values[1]; co = mq2.readCO(); //smoke = values[2]; smoke = mq2.readSmoke(); lcd.setCursor(0,0); lcd.print("LPG:"); lcd.print(lpg); lcd.print(" CO:"); lcd.print(co); lcd.setCursor(0,1); lcd.print("SMOKE:"); lcd.print(smoke); lcd.print(" PPM"); delay(1000); }

Download MQ2 Library

Download I2C LCD Display Library

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Considerations for the detection of hydrocarbon gases for risk control

Methane is lighter than air (possibility of accumulation under roofs) Ethane is slightly heavier than air (possibility of pooling at ground levels/pits) Propane is heavier than air (possibility of pooling at ground levels/pits) Butane is heavier than air (possibility of pooling at ground levels/pits)