Let's Control It

Hi all,

I've just got the SDS011 connected to the nodemcu with the ESPEasy mega 2.0. It works, but the values are very high, 60 to 100 for both variables. The air is clean and it should be near 0. Am I doing something wrong?

Regards

How do you know the air (and the sensor) are clean?
60-100 is something I also see here sometimes while I live in an area with relatively clean air (outside a small town in agricultural area in the North of the Netherlands).

Maybe the weather services also have some indicative levels for your area to compare values?

Have you an official station in the vincinity ? Check with e.g.: https://waqi.info
Lots of other sites available was the first to come up with google

If not you try a direct readout on a PC with DustSensorViewer.exe https://github.com/Galch/DustViewerSharp

FYI my last batch I got them in spring on first power up with Dust Viewer I was shocked that SDS was showing values >100, then I realised window was open and on closing after a couple of minutes values dwindled down. Pure air + loads of pollen

So pure ... yes maybe but how pure ? e.g. at time my station says 53 and it rained a lot so it should be clean ?
Don’t forget there is no T or RH% correction on the values the SDS gives !

SDS is just a good trend analyser no more no less, although it is fairly in sync with the official station the closest to home. Went over there a couple of times left a box overnight « stealth mode » over the fence and was not too shabby.

Success

Close to zero seems a bit too clean to me

Well, even with the HEPA filter on the intake, in my room, I get 80. If you check the luftdaten.info (all sensors are SDS011) you will see even in the center of the cities not more than 15.
Official value about 2km away is 5.
regards

grovkillen wrote: ↑29 Aug 2018, 15:41 Close to zero seems a bit too clean to me

What's "close"?

Last week, it was no more than 48.1 for the PM10 and most of the time it was between 10 ppm and 1.7 ppm.
This is just outside in our garden and it is often in sync with reports from official stations.
Last month, the daily averages were only 4 days above 10 ppm.

Ohh, I didn't know.

Update:
Got another SDS011 and now I have PM2.5 arround 10, which is normal. Ali refunded for the faulty.

bojan wrote: ↑09 Oct 2018, 07:50 Update:
Got another SDS011 and now I have PM2.5 arround 10, which is normal. Ali refunded for the faulty.

Good to hear and thanks for the update.