thstielow / raspi-bme680-iaq

Basic IAQ calculator for the Bosch bme680 sensor, compensating the humidity dependency and long-term drifts. Outputs a gas quality score on a range of 0-100%.
MIT License
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Polling sensor at different rates than once per second #2

Open samwaugh opened 1 year ago

samwaugh commented 1 year ago

Hey Thomas,

I was interested in using your code for a Magic Mirror project (see https://github.com/samwaugh/MMM-BME680) and I was wondering what happens if the bme680IAQ code is polled at rates other than once a second?

This is the first project I've done with node.js so I'm still trying to determine if I'm implementing things correctly. It is getting called every 30 seconds I believe.

Thanks for any help,

Sam

thstielow commented 1 year ago

Hi Sam,

the polling frequency will change the total magnitude of the gas resistance. When polling at slower rates, the observed resistance will drop, because air compunds have more time to react with the cold surface. Just as with the lower resistance during burn-in when firing up the sensor.

I genuinely do not know how this will affect the controbution of the humidity to the overall value. I hope that it can be solved by simply adapting the value of ph_slope.

I am very curious about your results!

Best, Thomas