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