CO2 Sensor (Arduino compatible) SKU: SEN0159 Contents [hide] 1 Introduction 2 Specification 3 Tutorial 3.1 Connecting Diagram 3.2 Sample code1 3.3 Sample code2 3.4 Result 4 Trouble shooting 5 More Introduction Greenhouse Effect is melting the iceberg every minute, By knowing the exact concentration of CO2, we can do something to reduce the CO2 and to protect our earth. For that reason, an HQ CO2 sensor is designed by DFRobot engineer. This is the first CO2 sensor in OSHW market. The output voltage of the module falls as the concentration of the CO2 increases. The potentiometer on board is designed to set the threshold of voltage. As long as the CO2 concentration is high enough (voltage is lower than the threshold), a digital signal (ON/OFF) will be released.