Shenzhen EF ELECFREAKS MG811 CO2 Gas Sensor

The Shenzhen EF ELECFREAKS MG811 CO2 Gas Sensor is a high-performance electrochemical sensor module designed for accurate carbon dioxide detection. Based on the MG811 sensor element, it provides reliable analog voltage output proportional to CO2 concentration, making it ideal for environmental monitoring, air quality control, and educational projects. The module operates at 5V DC and features a 3-pin header interface for easy integration with microcontrollers like Arduino, Raspberry Pi, and micro:bit (via adapter/shield).

Advantages

High sensitivity to CO2 with low cross-sensitivity to alcohol and carbon monoxide ensures accurate readings. The solid electrolyte galvanic cell principle offers long-term stability and a lifespan exceeding 5 years. With a detection range of 400-10000 ppm and fast response/recovery times (≤150 seconds), it is suitable for real-time monitoring applications. The module requires an initial preheat time of 48 hours for optimal performance, followed by a 30-minute operational preheat.

Suitable for

• Indoor air quality monitoring
• Greenhouse CO2 level control
• HVAC systems
• Environmental science experiments
• DIY electronics and IoT projects

Key specifications

• Sensor Type: Electrochemical CO2 Gas Sensor
• Sensor Model: MG811
• Detection Gas: Carbon Dioxide (CO2)
• Detection Range: 400 - 10000 ppm
• Operating Voltage: 5V DC
• Output Type: Analog Voltage Output (0-2V corresponding to 400-10000 ppm)
• Interface: 3-pin Header (VCC, GND, AO)
• Heater Voltage: 6V DC
• Heater Resistance: 30Ω ± 3Ω
• Response Time (T90): ≤ 150 seconds
• Recovery Time (T90): ≤ 150 seconds
• Operating Temperature: -10°C to 50°C
• Operating Humidity: 5% to 95% RH (non-condensing)
• Initial Preheat Time: 48 hours
• Operational Preheat Time: 30 minutes
• Lifespan: > 5 years

Recommendations

For best accuracy, allow the sensor to preheat for 48 hours before first use. Use an analog-to-digital converter (ADC) to read the output voltage. Calibration in fresh air (400 ppm CO2) is recommended. Avoid exposure to high concentrations of alcohol or carbon monoxide to prevent sensor damage.