How to Detect Concentration of Gas by Using MQ2 Sensor

MQ-2 Gas sensor is used to detect the gas level around the area. 

This sensor able to use as home or factory gas leak monitoring, suitable for gas, butane, propane, methane, alcohol, hydrogen, smoke and other monitoring devices.

Specification:

size: 35mm x 22mm x 23mm (length x width x height) Main chip: LM393, ZYMQ-2 gas sensors Working voltage: DC 5 VCharacteristics:With a signal output instruction. Dual signal output (analog output, and high/low digital output) 0 ~ 4.2V analog output voltage, the higher the concentration the higher the voltage. Better sensitivity for gas, natural gas, city gas. With a long service life and reliable stability. Rapid response and recovery characteristics.

The materials that you need
-Arduino Uno
-MQ2 gas sensor
-Potentiometer
-LCD 20x4
-LED

Understanding Pin Definition of MQ2 Gas Sensor

Set Up the Circuit Above

LCD pins
-Pins D7 , D6 , D5 , D4 connect to arduino digital pins 2,3,4,5 respectively.
-Pins A and K connect to 5V and GROUND respectively
-Pins VSS and VDD connect to Ground and 5V respectively.
LED
-Use as a LED indicator for the calibration process of the MQ2 gas sensor
-Connect to digital pin 13 of Arduino Uno
MQ2 Gas Sensor
-Analog output connect to the A0 of arduino
Potentiometer
-Center pin connect to the V0 of LCD display
-Other two pins just connect to 5V and GROUND respectively
*Note: All of pins above is configured regarding the circuit figure above. You can configure the connection yourself regarding your favourite.

Programming the Arduino Uno



code is not available for now ......