MQ-5 Gas Sensor Module For H2, LPG, CH4, CO Detector Module

The MQ-5 Gas Sensor Module is a high-sensitivity gas detection module designed to detect Liquefied Petroleum Gas (LPG), Natural Gas (Methane), Town Gas, Hydrogen (H₂), and other combustible gases. Based on the MQ-5 Metal Oxide Semiconductor (MOS) gas sensor, the module is widely used in gas leak detection systems, industrial safety equipment, smart home automation, environmental monitoring, and IoT-based gas sensing applications.

The module provides both analog and digital outputs, making it suitable for a wide variety of embedded applications. The analog output produces a voltage proportional to the detected gas concentration, allowing continuous gas monitoring, while the digital output changes state when the gas concentration exceeds a user-adjustable threshold set using the onboard sensitivity potentiometer. This flexibility allows the module to function as both a gas concentration monitor and a gas leak alarm.

Operating from a standard 5V DC supply, the MQ-5 module is fully compatible with Arduino, ESP32, ESP8266, Raspberry Pi (with an external ADC for analog readings), STM32, PIC, AVR, ATmega, NodeMCU, and other popular microcontroller platforms. Its compact PCB design, reliable performance, long service life, and simple interface make it suitable for students, hobbyists, engineers, and industrial developers.

The MQ-5 sensor is commonly used for detecting gas leaks in homes, kitchens, factories, warehouses, laboratories, and industrial facilities where continuous monitoring of combustible gases is essential for safety.

Working Principle

The MQ-5 operates using Metal Oxide Semiconductor (MOS) sensing technology. The sensing element consists of a tin dioxide (SnO₂) layer heated to its operating temperature by an internal heating element.

When combustible gases such as LPG, Methane (Natural Gas), Hydrogen, or Town Gas come into contact with the heated sensing surface, the electrical resistance of the sensing material changes. The amount of resistance variation depends on the concentration of the surrounding gas.

The onboard signal conditioning circuit converts this resistance change into an analog voltage that can be measured by a microcontroller. An integrated comparator continuously compares the signal with a preset threshold and generates a digital HIGH or LOW output whenever the gas concentration exceeds the selected limit.

The onboard potentiometer enables users to adjust the detection sensitivity and threshold according to specific application requirements and environmental conditions.

Key Features

High-sensitivity combustible gas detection.

Detects LPG, Natural Gas (Methane), Town Gas, Hydrogen, and other combustible gases.

Based on the MQ-5 Metal Oxide Semiconductor gas sensor.

Analog output for continuous gas concentration monitoring.

Digital output with adjustable detection threshold.

Onboard sensitivity adjustment potentiometer.

Fast response and recovery time.

Stable and reliable performance.

Long operational lifespan.

Low power consumption.

Compact PCB design.

Built-in power and detection indicator LEDs.

Compatible with Arduino, ESP32, ESP8266, Raspberry Pi (with external ADC), STM32, PIC, AVR, ATmega, NodeMCU, and PLC systems.

Suitable for industrial, commercial, educational, and DIY electronics projects.

Technical Specifications

Sensor Type: Metal Oxide Semiconductor (MOS)

Sensor IC: MQ-5

Operating Voltage: 5V DC

Output Type: Analog (AO) and Digital (DO)

Detection Method: Gas Concentration Sensing

Detection Range: Approximately 200–10,000 ppm (gas dependent)

Detectable Gases: LPG, Natural Gas (Methane), Town Gas, Hydrogen (H₂), and Other Combustible Gases

Sensitivity Adjustment: Onboard Potentiometer

Response Time: Fast

Recovery Time: Fast

Power Consumption: Low

Interface: VCC, GND, AO, DO

Operating Temperature: Suitable for standard indoor operating environments

Module Type: Combustible Gas Sensor

Applications

LPG gas leak detection.

Natural gas leak monitoring.

Hydrogen gas detection.

Town gas monitoring.

Kitchen gas safety systems.

Home gas leak alarms.

Industrial gas monitoring.

Factory and warehouse safety.

Smart home automation.

IoT gas monitoring systems.

Environmental monitoring.

Robotics and automation.

Educational electronics projects.

DIY electronics and prototype development.

Research and laboratory experiments.

Safety alarm and warning systems.