SPECIFICATIONS

Brand Name: NONE

High-concerned chemical: none

Origin: Mainland China

Use: Gas Sensor

MQ-2 Sensor Introduction:

The MQ-2 gas sensor uses tin dioxide (SnO₂), a material with low conductivity in clean air. When flammable gases are present in the environment, the sensor’s conductivity increases along with the gas concentration.

A simple circuit can convert this change in conductivity into an output signal that corresponds to the gas concentration. The MQ-2 sensor offers high sensitivity to LPG, propane, and hydrogen, and it is also suitable for detecting natural gas and other flammable vapors. Capable of sensing multiple flammable gases, it is a cost-effective choice for various applications.
Product Specifications

Product Model: MQ-2
Product Type: Semiconductor Gas Sensor Element
Standard Package: Bakelite (Black Bakelite)
Detectable Gases: Flammable Gases, Smoke
Detection Concentration: 300-10000ppm (for flammable gases)

Standard Circuit Conditions

Circuit Voltage (Vc): ≤24V DC
Heating Voltage (VH): 5.0V±0.2V AC or DC
Load Resistance (RL): Adjustable

Gas Sensor Element Characteristics Under Standard Test Conditions

Heating Resistance (RH): 31Ω±3Ω (at room temperature)
Heating Power Consumption (PH): ≤900mW
Sensitive Body Surface Resistance (Rs): 2KΩ-20KΩ (in 2000ppm C3H8 environment)
Sensitivity (S): Rs (in air) / Rs (in 1000ppm isobutane) ≥5
Concentration Slope (α): ≤0.6 (R3000ppm/R1000ppm C3H8)

Standard Test Conditions

Temperature & Humidity: 20℃±2℃; 65%±5% RH
Standard Test Circuit: Vc: 5.0V±0.1V; VH: 5.0V±0.1V
Preheating Time: Not less than 48 hours

Module Applications:
Suitable for gas leak detection in homes and factories. Detects LPG, butane, propane, methane, smoke and other flammable gases.

Module Features:

High-quality double-layer PCB with power and TTL output indicators.
Provides DO (TTL) digital output and AO analog output.
TTL output is active low (LED lights when low; can connect directly to MCU or relay module).
Analog output voltage increases with gas concentration.
Good sensitivity to LPG, natural gas, city gas and smoke.
Four mounting holes for easy installation.
Dimensions: 32(L) × 20(W) × 22(H) mm.
Long service life and stable performance.
Fast response and recovery.

Electrical Specifications:
Input Voltage: DC 5V
Power Consumption (Current): 150mA
DO Output: TTL 0/1 (approx. 0.1V / 5V)
AO Output: 0.1–0.3V (clean air), up to around 4V at high concentration

Important Note:
Allow 20 seconds of preheating after power-on for stable readings. A slight temperature rise is normal due to the internal heating element; excessive heat (too hot to touch) is not normal.

Wiring: