MQ-2 Liquified Gas/Smoke Sensor

Description

The MQ-2 is a versatile, low-cost sensor designed to detect a wide range of combustible gases and smoke. It features a fast response time and high sensitivity, making it ideal for safety applications.

• Detection Range: 300 to 10,000 ppm (parts per million).
• Target Gases: Primarily LPG (Propane/Butane), Methane, Hydrogen, and Smoke. It can also detect Alcohol and Carbon Monoxide (though less sensitively than dedicated sensors).
• Operating Voltage: 5V DC.
• Interface: Most modules provide both:
  • Analog Output (AO): Provides a varying voltage based on gas concentration (higher gas = higher voltage).
  • Digital Output (DO): Provides a simple High/Low signal based on a threshold you set with the onboard potentiometer.
• Internal Heater: The sensor contains a small internal heater. Because of this, the sensor will feel warm to the touch during operation—this is normal and necessary for the chemical reaction to occur.

What It Is Used For

The MQ-2 is a “general-purpose” safety sensor used in environments where multiple types of gas leaks could be a threat:

1. Home Gas Leak Alarms: Detecting leaks from gas stoves or heaters (LPG/Natural Gas).
2. Fire Detection: Acting as an early-warning smoke detector for DIY fire alarm systems.
3. Industrial Safety: Monitoring for hydrogen or combustible gas buildups in small workshops or factories.
4. Portable Gas Detectors: Used in handheld battery-powered devices to check for leaks in pipes.
5. Air Quality Monitoring: Integrated into smart home hubs to trigger ventilation fans when smoke or high gas levels are detected.