How to calibrate the CO2 sensor?

CO2 sensors need to be calibrated regularly to ensure accuracy. The usual calibration methods include manual calibration and automatic calibration. Take the Gravity: PWM Infrared Carbon Dioxide Sensor (SEN0219) as an example.

Manual calibration Manual calibration zero point is to calibrate the zero point of the sensor by shorting the HD and GND of the sensor, and the low level needs to be maintained for more than 7 seconds. Before calibrating the zero point, please ensure that the sensor has been running stably for more than 20 minutes at a concentration of 400ppm.

Automatic calibration The automatic calibration function means that the sensor can intelligently judge the zero point and calibrate it according to the environmental concentration after running continuously for a period of time. The calibration period is every 24 hours from the start of power-on, and the zero point of automatic calibration is 400ppm. The automatic calibration function is suitable for office and home environments.