The MQ2 Gas Sensor Module is a versatile and essential safety component for monitoring indoor air quality and detecting combustible gases. At Electrapac, we recommend this module for students and hobbyists building fire alarms, gas leak detectors, or smart home security systems.

Product Overview

The MQ2 is a metal oxide semiconductor (MOS) type gas sensor. It uses a small internal heater to warm up a sensing element (SnO2), which changes its electrical resistance based on the concentration of specific gases in the air. It is highly sensitive to LPG (Propane/Butane), Methane, Smoke, and Hydrogen, making it a "multi-purpose" detector for domestic and industrial safety.

Key Features for Electrapac Customers

• Dual Output Mode: Features both an Analog Output (AO) for precise concentration measurements and a Digital Output (DO) for simple "Yes/No" threshold detection.

• Adjustable Sensitivity: The onboard multi-turn potentiometer allows you to set the exact gas concentration level at which the Digital Output triggers.

• High Sensitivity & Fast Response: Designed to detect even small traces of smoke or gas leaks before they become hazardous.

• Stable Lifespan: Built with high-quality materials to ensure a long operational life and stability against temperature and humidity fluctuations.

• Standard 4-Pin Design: Includes Vcc, GND, DO, and AO, making it fully compatible with Arduino, Raspberry Pi, and ESP32.

Wiring & Calibration Guide

Integrating the Electrapac MQ2 sensor into your project is straightforward.

1. VCC: Connect to 5V (The internal heater requires a steady 5V supply).

2. GND: Connect to common ground.

3. DO (Digital Out): Connect to a digital pin to trigger an alarm/buzzer.

4. AO (Analog Out): Connect to an Analog-to-Digital Converter (ADC) pin for data logging.

Pro-Tip: The Burn-in Period. When you first use a new MQ2 sensor, it must stay powered on for 24 to 48 hours to "burn-in" and stabilize the sensing element. Afterward, on daily use, give it about 60 seconds to preheat before trusting the readings. If the sensor feels warm to the touch, this is normal behavior due to the internal heating coil.

Primary Applications

• Gas Leak Alarms: Detecting leaks in LPG cylinders or natural gas pipelines at home.

• Industrial Smoke Detectors: Identifying the presence of smoke or fire in workshops or warehouses.

• Air Quality Monitoring: Measuring environmental pollution levels in urban areas.

• Breathalyzer Projects: Detecting alcohol vapor in experimental DIY breathalyzers.

• Kitchen Safety Systems: Automatically activating an exhaust fan when high levels of cooking gas are detected.

Why Shop at Electrapac?

We supply the Standard 4-Pin MQ2 Module featuring the reliable LM393 comparator to ensure your safety projects respond accurately when it matters most. Visit us at www.electrapac.com for the sensing technology that protects your home and workspace.