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Arduino imeplementation for CO2 sensors of the MH-Z series (Intelligent Infrared CO2 Module)
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tobiasschuerg Make times `unsigned long` to avoid overlow
on 16 bit architectures. Closes #10
Latest commit af5c565 Sep 8, 2019

MH-Z14A, MH-Z19B CO2 ... Module

Arduino implementation for MH-Z CO2 sensors such as MH-Z14A, MH-Z18B (as I didn't find all info in one place).

The sensor is available for ~20 bucks at the usual places.


See example.

PPMuart: 602, PPMpwm: 595, Temperature: 23

Implementation details

C ppm = 5000 * (T_high - 2 ms) / (T_high + T_low - 4ms)

The implementation is mostly based on



More info about the sensor:

Further reading:

(russuian, but google translate does a good job)

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