Product Description
The MQ-9 CO, Methane & LPG Gas Sensor Module is a widely used gas detection sensor designed to sense carbon monoxide (CO), methane (CH₄), LPG, and other combustible gases in the surrounding environment. The sensor element changes resistance based on gas concentration, and the module outputs a corresponding analog voltage that can be read via the ADC of microcontrollers such as Arduino, ESP32, STM32, and Raspberry Pi (with ADC interface).
This module is commonly used in gas leakage detection systems, safety alarms, smart home automation, environmental monitoring kits, industrial safety projects, and IoT gas detection networks. The module’s sensitivity can be adjusted using an onboard potentiometer.
Key Features
Detects CO, Methane (CH₄), LPG and other combustible gases
Analog voltage output proportional to gas concentration
Simple 4-pin interface (VCC, GND, DO/Analog Out)
Sensitivity adjustable via onboard potentiometer
Works with 3.3V – 5V systems
Compatible with Arduino, ESP32, STM32
Package Includes
1 × MQ-9 Gas Sensor Module
Technical Specifications
Parameter | Specification |
Sensor Model | MQ-9 |
Detectable Gases | CO, Methane, LPG, and other flammable gases |
Output | Analog voltage |
Operating Voltage | 3.3V – 5V |
Interface | Analog & Digital (DO optional) |
Heating Element | Yes |
Preheat Time | ~24–48 hours for stable readings |
Compatible MCU | Arduino, ESP32, STM32, Raspberry Pi (with ADC) |
Dimensions | ~30 × 20 × 15 mm |
Applications
Gas leakage detection systems
Smart home safety alarms
Industrial environment monitoring
IoT gas sensing networks
LPG kitchen safety detection
DIY embedded sensor projects