A
Anonymous
Mar 20, 2026
Rating: 5/5
University project success
Used the MQ-2 for a smoke detection prototype. Responds quickly to lighter smoke.
Description
Tmall 14-Year Established Store Risym Weixin High-Quality Best-Seller
Reviews
Attributes
| Brand | - |
| Category | Electronic Components / Maker DIY / Computer Hardware, Monitors & Peripherals |
| Origin | - |
| Sensor Models | MQ-2, MQ-3, MQ-7, MQ-9, MQ-135 |
| Operating Voltage | 5V DC |
| Output Signal | Digital Switch Output (0/1) and Analog Output |
| Comparator Chip | LM393 Wide Voltage Comparator |
| PCB Dimensions | 32mm x 20mm |
| Preheat Time | 24-48 Hours for stable baseline |
| Sensitivity | Adjustable via Onboard Potentiometer |
| Indicator LEDs | Power LED and Digital Switch Output LED |
| Interface Type | 3-Pin Header (VCC, GND, OUT) |
| Application | DIY Electronics, Prototyping, Educational Kits |
5 reviews
A
Anonymous
Mar 17, 2026
Rating: 5/5
Perfect for learning
These modules are great for understanding gas sensing. Easy to interface with microcontrollers.
A
Anonymous
Mar 13, 2026
Rating: 4/5
Good quality
Works well but requires patience for the preheat time. Value for money is excellent.
A
Anonymous
Mar 09, 2026
Rating: 5/5
Reliable modules
Bought the variety pack. All sensors tested functional out of the box.
A
Anonymous
Jan 29, 2026
Rating: 4/5
Note on safety
Great for prototypes but remember these are not certified for home safety alarms.
5 FAQ
Q: Are the pins labeled clearly?
A: Yes, the PCB has silk screen labels for VCC, GND, and OUT for easy connection.
Q: Can I use this for a home safety alarm system?
A: No, these modules are for educational and prototyping purposes only. Please use certified safety devices for home protection.
Q: What is the required power supply?
A: The module operates best on 5V DC. The analog output can be read by 3.3V logic boards.
Q: Does MQ-3 detect alcohol only?
A: MQ-3 is primarily sensitive to alcohol vapor, but cross-sensitivity to other gases may occur.
Q: How long before the sensor is accurate?
A: We recommend a preheat time of 24 to 48 hours for the first use to stabilize the baseline.
