- Gas leaks cause air pollution and are hazardous, they may also lead to fire outbreaks.
- Gas sensors notify us whenever there is a gas leak by releasing an output signal similar to the amount of gas leak.
- The Mq4 gas sensor is the most used methane gas sensor, as it is less sensitive to other gases or alcohol.
- It is a semiconductor gas sensor that detects the presence of methane (CNG) gas at concentrations from 300 ppm to 10,000 ppm, it is a range suitable for detecting gas leaks.
- The sensor’s analog voltage interface requires only one analog input pin from the microcontroller.
- The example is- this sensor could detect if someone left a gas stove on but not lit.
Pin Configuration
- AO (Analog output Pin)- an output is released in an analog form whose value depends on the efficiency of sound. (0 to 5 V).
- DO(Digital output Pin)- a digital output whose logic high and logic low are determined with the use of a potentiometer.
- VCC (Power supply)- voltage 5v is given.
- GND(ground)- connected to ground.
- A, B, and H are another group of pins.
- A: Anyone is used as the output pin and the other as GND.
- B: both are connected to supply.
- H: One connected to the ground and the other to the supply.
- Pins A and B can be interchanged.
Features of MQ4 Methane Gas Sensor
- Detection Gas- Natural Gas/Methane
- Concentration- 300-10000ppm
- Supply Voltage- <24V
- Heater Voltage- 5.0V ± 0.2V
- Load Resistance- Adjustable
- Heater Resistance- 31Ω ± 3Ω
- Heater Consumption- <900mW
Applications of MQ4 Methane Gas Sensor
- Gas leak detection at home or in industries.
- Gas sensors are required near large garbage bins.