MG811 CO2 Carbon Dioxide Sensor - (AD14214)

Description:

This sensor is designed to capture CO2 in the environment. "Carbon dioxide is a colorless, odorless gas vital to life on Earth. This chemical compound found in nature consists of one carbon atom bonded with two double covalent bonds to two oxygen atoms. CO2 exists in Earth's atmosphere as a trace gas at a concentration of about 0.04% (400 ppm) by volume. Natural sources include volcanoes, hot springs, geysers, and it is released by carbonate rocks when dissolved in water and acids. Since CO2 is soluble in water, it occurs naturally in groundwater, rivers, lakes, ice fields, glaciers, and seas."

And this tutorial focuses on this sensor, as it is the most frequently mentioned commercial sensor, even though there are few Arduino applications and even fewer tutorials in Spanish.

This sensor (the gray one) together with the module (all the others) contains a circuit to amplify or adjust the sensitivity depending on the environment where it is to be used. It has a comparator with adjustable threshold and an analog output, which the microcontroller will read. This sensor can read concentrations from 350 to 100,000 ppm (parts per million).

Sensor characteristics:

- Voltage 5V or more.

- Digital output DO (comparator)

- Analog output AO (amplifier)

- Temperature comparator output

- Potentiometer to adjust amplification

- Potentiometer to adjust comparator

- Weight 10 g

- The sensor heats up and can be felt to the touch. The voltage increases until it stabilizes. Once the sensor is warm, it will be ready to detect CO2.

- The analog output has a range of 0 to 2V. A higher output voltage means a lower gas concentration. For more information, refer to the datasheet.

- When the ambient temperature changes, the output voltage also varies, and the CO2 sensor is more effective at higher temperatures.

Reference link