The hardest part of this project was calibration. While working on calibration I had found a great contributor of the Sniffing Tricket by Georg Krocker. In his project he details how to calibrate the sensors and also gives a GREAT library for the MQ135. https://github.com/GeorgK/MQ135
Discussions
Become a Hackaday.io Member
Create an account to leave a comment. Already have an account? Log In.
Hi do you know how the author get these values from?
#define RZERO 76.63
/// Parameters for calculating ppm of CO2 from sensor resistance
#define PARA 116.6020682
#define PARB 2.769034857
/// Parameters to model temperature and humidity dependence
#define CORA 0.00035
#define CORB 0.02718
#define CORC 1.39538
#define CORD 0.0018
Are you sure? yes | no