So the CO2 sensor that we ordered has some issues... at least the spec sheets do. Yes, that was plural...spec sheets. On one spec sheet the output voltage is 30-50mV, and the graph it provides reads that the output voltage is 265-325mV. On the spec sheet for the module the CO2 sensor plugs into, it refers to the CO2 sensor having a voltage output of 100-600mV. What?!?!?!?
It appears we must do our own calibration, using the grey wolf as gospel truth. Over 2 hours of careful measuring, we plotted the voltage function of the sensor in relation to the CO2 ppm and took 37 points of data, more closely spaced where we would be using the sensor. We measured from 800ppm to 80000ppm and found that the sensor becomes less responsive at very high concentrations. On a log graph, it looks fairly linear. The y-axis is ppm and the x-axis is voltage output by our sensor.
With that many data points, it should be fairly easy to interpolate ppm based on voltage. Our range of concern is between primarily 1000-5000ppm. The actual data looked like this, although the program cut off the first 25 minutes.
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