Dec 17, 2020· The MH-Z19C module is a next-generation CO2 sensor based on the non-dispersive infrared (NDIR) principle. MH-Z19 C is the successor of the widely popular MH-Z19 B. See below for a comparison. The MH-Z19C 400~2000ppm CO2 sensor has built-in temperature compensation and communicates over UART and PWM with the host controller.
MH-Z19 Vout to Arduino Vout(5V) MH-Z19 GND to Arduino GND MH-Z19 Tx to Arduino Digital Pin (Serial Rx pin) MH-Z19 Rx to Arduino Digital Pin (Serial Tx pin) other MH-Z19 pins are not used. Read sample source code. It's very simple ! caution. MH-Z19 is supporting PWM , but this library is supporting only serial connection.