MQ-4 Methane Gas Sensor Module

MQ4 Gas sensor is a Metal Oxide Semiconductor (MOS) type Gas Sensor mainly used to detect the Methane (CNG) gas concentration in the air either at home or in industry. This sensor contains a sensing element, mainly aluminum-oxide based ceramic, coated with Tin dioxide, enclosed in a stainless-steel mesh. Whenever gas comes into contact with the sensing element, the resistivity of the element changes. The change is then measured to get the concentration of the gases present. Its sensing range of 300-10000 PPM is suitable for gas leak detection. The combustion of Methane is highly exothermal means it will release a vast amount of heat if ignited which when used in a controlled way is beneficial but if an accident occurs it will be devastating.

Specifications

• Power requirements: VCC - 5V±0.1
• DO output: TTL digital 0 and 1 (0.1 and 5V)
• AO output: 0.1-0 .3 V (relative to pollution), for maximum concentration of a voltage of about 4V
• Detection Gas: Natural gas/Methane
• Detection Concentration: 200-10000ppm (Natural gas / Methane)
• Interface: 1 TTL compatible input (HSW), 1 TTL compatible output (ALR)
• Heater consumption: less than 750mw
• Operating temperature: 14 to 122 °F (-10 to 50°C)
• Preheat time: Over 24 hours

Product Description

To use the Sensor Module, you have power the device with 5V supply and the Power LED will start to glow. You should give it some time for its preheating period before start reading the output. While measuring the gas present, the Output LED will glow in a specific concentration of the gas. You can change it by using the potentiometer. Else you can also use the Analog Output to see how your program reacts to different concentrations of gases present.

Additional Resources

• MQ4 sensor Datasheet
• MQ4 Mehane Gas Sensor Based Arduino Project