Anonymous
Mar 18, 2026
Rating: 5/5
Perfect for Arduino Projects
This sensor works flawlessly with my Arduino Uno. The analog output is stable after the initial warm-up period. Great value for the price.
Description
Reviews
| Brand | - |
| Category | Robotics / STEM Teaching Tools / Sensors |
| Origin | - |
| Model Number | MQ-7 |
| Detection Gas | Carbon Monoxide (CO) |
| Operating Voltage | 5V DC |
| Output Signal | Analog and Digital (TTL) |
| Heating Current | 150mA (approx) |
| Sensitivity Range | 20 - 2000 ppm |
| Response Time | < 60 seconds |
| Recovery Time | < 60 seconds |
| Interface Type | 3-Pin Header (VCC, GND, DO/AO) |
| Dimensions | 32mm x 20mm x 22mm |
Anonymous
Mar 18, 2026
Rating: 5/5
Perfect for Arduino Projects
This sensor works flawlessly with my Arduino Uno. The analog output is stable after the initial warm-up period. Great value for the price.
Anonymous
Mar 18, 2026
Rating: 3/5
Works but gets hot
The sensor functions as described, but the heating element gets quite hot during operation. Make sure your enclosure has ventilation.
Anonymous
Mar 11, 2026
Rating: 4/5
Solid performance
We bought ten of these for our workshop. Most worked perfectly out of the box. One required a bit of soldering touch-up on the pins.
Anonymous
Mar 08, 2026
Rating: 5/5
Great for learning
Excellent component for understanding how gas sensors work. The dual output (analog/digital) makes it versatile for different microcontrollers.
Anonymous
Mar 07, 2026
Rating: 4/5
Good sensitivity, needs calibration
The module detects CO well, but you definitely need to calibrate the potentiometer for your specific environment. Instructions could be clearer.
Anonymous
Mar 05, 2026
Rating: 5/5
Reliable and Compact
Used this in a mobile robot project to detect gas leaks in simulated environments. It responds quickly and the digital output threshold is easy to adjust.
Q: How do I adjust the sensitivity threshold?
A: There is a blue potentiometer on the board. Rotate it clockwise to increase sensitivity (lower threshold) and counter-clockwise to decrease sensitivity until the LED indicator triggers at your desired gas concentration.
Q: What is the logic level for the digital output pin?
A: The digital output (DO) provides a TTL signal, which means it outputs 0V for low and 5V for high, making it compatible with 5V microcontrollers like Arduino and ESP8266.
Q: Can this sensor detect natural gas or methane?
A: While the MQ-7 is optimized for Carbon Monoxide, it may show some cross-sensitivity to other combustible gases like hydrogen and methane, but for those, we recommend the MQ-4 or MQ-5 models for better accuracy.
Q: Does this module require a warm-up time before reading accurate values?
A: Yes, like most metal oxide sensors, the MQ-7 requires a warm-up period of approximately 24-48 hours for initial stabilization, and about 1-2 minutes before each accurate reading cycle.
Q: Is this sensor suitable for life-safety alarm systems in homes?
A: This module is intended for educational, prototyping, and industrial monitoring purposes. For residential life-safety alarms, please use certified UL-listed commercial alarm units.