IR Co2 accuracy question

Is the co2 sensor in the pulse the NDIR type ?

The CO2 sensor is a dual-chamber NDIR with an accuracy of ±(50ppm + 3%MV)

Ok. So I read a long writup on how ndir type sensors are only accurate at their calibration temp. They are talking about how fewer or more air molecules in the chamber via from heating and cooling and it tricks the ndir to think the co2 is higher but in reality it’s just fewer air molecules so the concentration of co2 increases in the chamber but in reality it’s not higher because temperature doesn’t directly effect co2 concentration is what it’s saying. Maybe that’s the plus or minus 50 ? I’ve seen diff co2 levels myself at diff temps which made me research this in the first place .


Thats a good point.

I don’t think the sensor takes into account the air pressure & temperature when reporting the value but I would have to double check that.

I checked some numbers w/ the ideal gas law and the effects of this are relatively minor, approximately 2% per 10F, so I wouldn’t worry about it too much.

Ok great. Thank you for looking into it. You guys are the BEST… much appreciated

I took some time to look into it and can confirm that our sensor takes into account temperature and humidity, but not air pressure, so the effects of air pressure might distort the readings slightly, but the effect should be relatively small.

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