In this Tutorial, We are Going To Make Smoke Detection using MQ-2 Gas Sensor
Introduction
Hardware Table
Circuit Diagram
Working Explanation
The MQ-2 smoke sensor is sensitive to smoke and to the following flammable gases:
- LPG
- Butane
- Propane
- Methane
- Alcohol
- Hydrogen
The resistance of the sensor is different depending on the type of gas.
The smoke sensor has a built-in potentiometer that allows you to adjust the sensor sensitivity according to how accurately you want to detect gas.
The voltage that the sensor outputs changes accordingly to the smoke/gas level that exists in the atmosphere. The sensor outputs a voltage that is proportional to the concentration of smoke/gas.
In other words, the relationship between voltage and gas concentration is the following:
- The greater the gas concentration, the greater the output voltage
- The lower the gas concentration, the lower the output voltage