SPECIFICATIONS

Product Description

MQ series gas sensor kit contains 9 popular gas sensor modules: MQ‑2, MQ‑3, MQ‑4, MQ‑5, MQ‑6, MQ‑7, MQ‑8, MQ‑9, MQ‑135.
These are semiconductor gas sensors for detecting flammable gas, alcohol, methane, carbon monoxide, hydrogen, air quality and other harmful gas.
Each module provides analog output and digital output, compatible with Arduino, ESP32, STM32, Raspberry Pi and other microcontrollers.
Ideal for maker DIY projects, gas alarm systems and environmental monitoring.

What each sensor detects

• MQ‑2: Smoke, LPG, propane, hydrogen, flammable gas
• MQ‑3: Alcohol vapor
• MQ‑4: Methane, natural gas
• MQ‑5: Coal gas, liquefied gas, natural gas
• MQ‑6: LPG liquefied petroleum gas
• MQ‑7: Carbon monoxide (CO)
• MQ‑8: Hydrogen gas (H₂)
• MQ‑9: Carbon monoxide & combustible gas
• MQ‑135: Air quality, ammonia, benzene, harmful gas

Key Features
✅ Dual output: AO analog signal + DO digital switch signal. On‑board potentiometer to adjust trigger threshold.
✅ DC 5V power supply, standard 4‑pin header for easy wiring.
✅ On‑board power indicator and signal indicator LED.
✅ Fast response & high sensitivity. Note: Sensor needs pre‑heat about 2 minutes for stable reading.
✅ Widely used for gas alarm device, environment monitoring, smart home, electronic maker experiments.

Specifications

• Operating Voltage: DC 5V
• Output: Analog(AO) + Digital(DO)
• Pin Definition: VCC, GND, AO, DO
• Pre‑heat Time: ≥ 2 minutes
• Compatible With: Arduino, ESP32, STM32, Raspberry Pi
• Operating Temperature: ‑10℃ ~ +50℃

1. 9‑in‑1 MQ gas sensor module kit, covers smoke, alcohol, methane, CO, hydrogen, air quality detection.
2. Dual signal output: analog AO and digital DO, adjustable sensitivity via onboard potentiometer.
3. DC 5V working voltage, standard 4‑pin interface, easy to connect with Arduino / ESP32 / Raspberry Pi.
4. Equipped with power and signal LED indicators for status observation.
5. Perfect for gas alarm DIY, environmental monitoring, electronic maker projects.