Forum Sensor.Community

PM correction on Luftdaten

As far as i can tell Luftdaten does not correct PM from SDS011 for humidity. Wouldn’t it make sense to do that there?
If not, why is there no such option in the firmware?

Tony

Yes, there is no correction for transparency reason.

If not, why is there no such option in the firmware?

You can program it and make a pull request in the Github. Do you have a good correction alogorithm ? We search for one a few years ago but we still haven’t find something satisfactory. Please send us some science publications reviewing the correction method.

Ok, so i didn’t overlook. There is Data adjusted with formulas for humidity correction · Issue #333 · opendata-stuttgart/sensors-software · GitHub
so i’ll test this.
FYI: Samen Meten - Dataportaal uses Luftdaten data. When you click on a sensor it will show Raw vs Corrected data.

Hi,

there is a paper from Bernd Laquai

http://www.opengeiger.de/Feinstaub/FeuchteKompensation.pdf

from 2018 where the problem is described in detail and a relatively good working compensation algorithm has been found. I thought this has already been implemented, as sensors that give massively false readings during the (autumn/winter) time of year, when fine dust is a matter, make barely sense. …

And just an FYI, it’s not just the sensor-reading itself that is an issue, it’s the electronics that are not able to deal with high humid environments. My new sensor-kit with SHT31 from netigo just refuses to even send data when it’s too moist, while power and wifi are all perfectly fine. I’m assuming that a drop of condensated water on top of two pins of any IC can destroy reliability for everything it does, but still, the tube I got with the kit is completely useless as a protective shield for that. In fact, in a way it even collects condense when it is warm enough without wind, because it locates the two circuit-boards higher than the two input exhausts of the tubing. Who thought of the tubing as a ‘good cage’ for the boards? Where’s the research showing that this will actually work well?

Personally, I think it’s much better to plastic-spray all parts, or use vulcanizing tape to cover everything but the sensors and the fan I/O.

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