MQ-2 Gas Sensor Module For H2, LPG, CH4, CO, Smoke or Propane Detector Module
MQ-2 Gas Sensor Module
Flammable Gas Detection Smoke Monitoring Safety Applications
The MQ-2 Gas Sensor Module is a widely used gas detection sensor designed to detect flammable and combustible gases such as Hydrogen (H), LPG, Methane (CH), Carbon Monoxide (CO), Propane, and Smoke. It is commonly used in gas leakage detection systems, fire safety systems, and air quality monitoring projects.
Infographic Overview
Basic Specifications
Feature | Details |
Operating Voltage | 5V DC |
Current Consumption | ~150 mA |
Heating Consumption | < 900 mW |
Detection Range | 200 10,000 ppm |
Response Time | &l) |
Sensitivity Adjustment | Yes (Potentiometer) |
Detectable Gases
The MQ-2 sensor is highly sensitive to several combustible gases.
Gas | Description |
Hydrogen (H) | Highly flammable gas |
LPG | Liquefied petroleum gas used in cooking |
Methane (CH) | Natural gas |
Carbon Monoxide (CO) | Toxic combustion gas |
Smoke | Fire and burning detection |
Propane | Fuel gas used in heaters and grills |
Pin Configuration
Pin | Function |
VCC | |
A0 | Analog output (gas concentration level) |
D0 | Digital output (threshold detection) |
Working Principle
The MQ-2 sensor operates using the metal oxide semiconductor (MOS) gas sensing principle.
Step-by-Step Operation
1 A heating coil warms the internal sensing material.2 The sensing material (usually Tin Dioxide SnO) reacts with gas molecules.3 When combustible gases are present, the sensor resistance changes.4 This change is converted into analog voltage output.5 The module's comparator circuit can trigger a digital signal when gas concentration exceeds a preset threshold.
Main Comp Adjustable potentiometer (sensitivity control) Power and output pins
Sensor Module Layout
MQ-2 Gas Sensor Module MQ-2 Sensor Gas Probe Sensitivity Adjuster(Potentiometer) VCC GND A0 D0
Common Applications
Gas leakage detection systems Fire and smoke detection systems Smart kitchen safety systems Industrial safety monitoring Smart home gas alarm systems Environmental monitoring projects
Compatible Microcontrollers
The MQ-2 module easily interfaces with popular development boards such as:
Arduino Uno
ESP32
Arduino Nano
Raspberry Pi
Advantages
Detects multiple flammable gases Low cost and easy to integrate Analog and digital outputs available Adjustable sensitivity Ideal for DIY electronics and robotics projects
Limitations
Requires preheating time (24 hours recommended for calibration) Cannot identify specific gas type precisely Sensitive to humidity and temperature changes Consumes relatively high current due to heating element
Example Project Idea
Smart Gas Leakage Alarm System
Components
MQ-2 Gas Sensor Module
ESP32 or Arduino Uno
Buzzer
LED Indicator Trigger buzzer alarm Display gas level Send IoT alert