Anonymous
Mar 25, 2026
Rating: 3/5
Sensitive to humidity
Works as expected but noticed some drift in high humidity conditions. Ensure you account for environmental factors in your code.
Description
Reviews
| Brand | - |
| Category | Electronic Components / Maker DIY / Computer Hardware, Monitors & Peripherals |
| Origin | - |
| Sensor Model | MQ-7 Semiconductor |
| Detection Target | Carbon Monoxide (CO) |
| Operating Voltage | 5V DC |
| Output Signal | Digital Switch (TTL) & Analog |
| Sensitivity | Adjustable via Potentiometer |
| Heating Voltage | 5.0V ± 0.1V |
| Load Resistance | Adjustable |
| Preheating Time | Minimum 24 Hours |
| Operating Temperature | -10°C to 50°C |
| Module Dimensions | 32mm x 20mm x 10mm |
Anonymous
Mar 25, 2026
Rating: 3/5
Sensitive to humidity
Works as expected but noticed some drift in high humidity conditions. Ensure you account for environmental factors in your code.
Anonymous
Mar 23, 2026
Rating: 5/5
Perfect for prototyping
Works great with my Arduino Uno. Easy to calibrate using the onboard potentiometer. Remember this is for hobby use, not a certified safety device.
Anonymous
Feb 17, 2026
Rating: 5/5
Fast shipping and well packed
Module arrived safely. Tested with a 5V relay module and it triggers correctly when exposed to CO source. Great for automation projects.
Anonymous
Feb 11, 2026
Rating: 5/5
Excellent for thesis project
Used this for an environmental monitoring system. The analog output provides good granularity for data logging. Highly recommend for students.
Anonymous
Jan 23, 2026
Rating: 4/5
Good value but needs patience
The sensor requires a long preheat time to stabilize. Once warmed up, readings are consistent. Good for learning gas detection logic.
Q: Can this sensor work with 3.3V microcontrollers?
A: The sensor heating element requires 5V. However, the output signals can be interfaced with 3.3V logic boards using a voltage divider or level shifter.
Q: Is this module certified for home safety alarms?
A: No, this module is designed for hobbyist and prototyping purposes only. Please use certified safety equipment for life-critical applications.
Q: Does this detect natural gas or propane?
A: MQ-7 is specifically sensitive to Carbon Monoxide. For combustible gases like propane or natural gas, please consider the MQ-5 or MQ-6 models.
Q: How long does the sensor need to preheat?
A: For stable and accurate readings, we recommend an initial preheating period of at least 24 hours before calibration.
Q: What are the pin functions on the module?
A: The module typically features four pins: VCC (Power), GND (Ground), DO (Digital Output), and AO (Analog Output).