MQ-2 Smoke & Flammable Gas Sensor Module (Fire & Leakage Safety Shield)
Deploy robust environmental safety and fire prevention networks with the industrial-grade MQ-2 Gas Sensor Module. Universally trusted for early-warning threat detection, this high-sensitivity module features an advanced tin dioxide semiconductor layer that acts as an excellent all-in-one shield against thick smoke, toxic leakage, and combustible gases.
The MQ-2 sensor is heavily optimized to detect Liquefied Petroleum Gas, butane, propane, methane, hydrogen, and airborne smoke particles with exceptional speed. It serves as an essential safety node for domestic kitchen fire alarms, commercial warehouse smoke monitoring grids, industrial automation control panels, and automated exhaust fan triggers.
Key Features
Broad-Spectrum Gas Tracking: Highly responsive to a wide array of hazards including kitchen smoke, engine exhaust, fuel gas leaks, and industrial vapors.
Dual Output Architecture: Built with both a Digital Output for instantaneous high/low safety alarm triggers and an Analog Output for real-time parts-per-million concentration mapping.
Adjustable Alarm Threshold: Features an onboard multi-turn potentiometer, allowing you to finely adjust the digital trigger point to match your specific clean-air background baseline.
Onboard Voltage Comparator: Assembled with a highly stable comparator integrated circuit, ensuring clean, sharp digital square waves that eliminate false triggers.
Explosion-Proof Stainless Steel Mesh: Designed with a dual-layer stainless steel mesh cover that protects the internal heated filament while keeping safe airflow moving into the sensor chamber.
Real-Time LED Status Monitoring: Equipped with two independent indicators—one for central power tracking and another that lights up instantly when smoke or gas levels pass your preset safety limit.
Technical Specifications
Feature | Specification |
Sensor Type | Semiconductor Gas Sensor (MQ-2) |
Target Hazards | Smoke, LPG, Butane, Propane, Methane, Hydrogen |
Operating Voltage | 5V DC Nominal |
Operating Current | Approx. 150 mA |
Detection Concentration Range | 300 to 10000 ppm (Parts-Per-Million) |
Output Type | Dual Output: Analog Output + Digital Output |
Active Logic State | Digital Output drops LOW (0V) when safety thresholds are crossed |
Mounting Layout | Pre-drilled screw holes for secure panel or wall attachment |
Board Dimensions | 32 mm x 20 mm x 22 mm |
Hardware Wiring & Pin Mapping
The module breaks out a 4-pin interface that maps directly to standard microcontrollers like Arduino, ESP32, STM32, and Raspberry Pi:
VCC: Connects to a stable +5V DC power supply rail. (Requires a dedicated 5V source to correctly power the internal heating element).
GND: System Ground Reference.
DO (Digital Output): Outputs a stable High/Low logic level. Connect this straight to a digital input or hardware interrupt pin. It stays HIGH in standard conditions and drops LOW when smoke or gas leakages cross your threshold.
AO (Analog Output): Outputs a varying voltage signal corresponding directly to the concentration of gas or smoke in the air. Connect this to an analog pin to process exact parts-per-million calculations.
Common Applications
Home Fire & Smoke Detectors: Build custom smart home alarm hubs that trigger loud piezoceramic buzzers or send push notifications if a fire breaks out in the kitchen.
Industrial Workshop Air Quality: Install near machinery setups, welding booths, or battery charging stations to activate exhaust ventilation fans automatically when smoke builds up.
Gas Leakage Security Panels: Mount close to floor levels or ceiling grids (depending on target gas weight) to register butane, propane, or methane plumbing failures.
Academic Automation Projects: An excellent, entry-level diagnostic module for university robotics labs, smart green-energy networks, and student engineering workshops.
💡 Operating Tip: The MQ-2 sensor requires a "Preheat / Burn-in" period before it can output accurate readings. After powering the module on for the very first time, let it sit powered up for 24 to 48 hours to balance the internal chemical sensing element. For subsequent uses, allow 1 to 2 minutes of warm-up time until the heater stabilizes. The module will become warm to the touch during normal operation—this is perfectly normal behavior for the internal heater loop.
Package Includes:
1 x MQ-2 Smoke Gas Sensor Module (4-Pin Breakout Board)