Here's an overview of the MQ-7 sensor module:

Purpose: It has a high sensitivity to carbon monoxide gas.

Sensitivity: It has a high sensitivity to methane and other combustible gases.

Principle: The sensor operates on the principle of a semiconductor gas sensor, where the resistance of the sensing material changes based on the concentration of CO gas.

Features:

Analog and Digital Output: Similar to other MQ series sensors, the MQ-7 module provides both analog and digital outputs. The analog output can be used to estimate the gas concentration, while the digital output can be configured to trigger alerts when CO concentration exceeds a predefined threshold.

Adjustable Sensitivity: Many modules include a potentiometer that allows users to adjust the sensor's sensitivity.

Affordability: The MQ-7 sensor module is cost-effective, making it a popular choice for gas detection projects.

Applications:

Safety Applications: The MQ-7 sensor is used for detecting carbon monoxide in environments like homes, offices, and industrial areas to ensure safety and prevent CO poisoning.

Indoor Air Quality: It can be utilized to monitor indoor air quality and ensure that CO levels are within safe limits.

Combustion Monitoring: The sensor can also be used to monitor combustion processes and detect the presence of CO in areas like furnaces, gas heaters, and stoves.

Using the MQ-7:

Powering the Sensor: The sensor typically requires a 5V DC power supply.

Calibration: To achieve accurate readings, calibration may be necessary. This involves exposing the sensor to clean air to establish a baseline resistance value.

Reading Values: Like previous MQ series sensors, you can use a microcontroller (such as Arduino) to read values from the MQ-7 sensor. Connect the analog output to an analog pin and the digital output to a digital input pin on the microcontroller.

Considerations:

Warm-Up Time: The sensor may require some time to warm up before it provides reliable readings.

Cross-Sensitivity: The MQ-7 sensor might exhibit cross-sensitivity to gases other than carbon monoxide. This can impact accuracy if other gases are present in the environment.

Environmental Factors: As with all gas sensors, environmental conditions like temperature and humidity can influence their performance.

When integrating the MQ-7 CO Carbon Monoxide Coal Gas Sensor Module into a project, proper calibration and considering potential cross-sensitivity are crucial for obtaining accurate and reliable CO concentration readings, especially due to the toxic nature of carbon monoxide.

Standard Test Conditions Of MQ-7 Sensor Module

Technical Details

Physical Attributes: MQ-7 Sensor Module

Integration with Arduino

Sample Code

Additional Details

Product Video

Useful Links

Documentation

Package Includes