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airquality
Posted: Thursday 28 January 2016 10:48
by htca
hi, I have my domoticz server up and running on a raspberry pi for a few days. Uptil now, I run a system which monitored several things, like gas, electricity and water use (selfmade monitoring system using a ADC and 3 sensors). I was able to add those to domoticz using dummy hardware and a counter. On my old server I also collect information about the airquality from internet (there is a station close to my home, which publishes on the internet). I would like to push them as well to domoticz, however my airquality is defined as mug/m^3 for 8 different polluting porticles. In the dummy hardware there is an airquality but thats for CO2 and defines only in ppm. I could use that, but it is a bit dirty to do (and not fully correct). I added 8 user variables, but it seems that I cannot log them as a device (is that correct). Can anybody give me hint howto do this?
Re: airquality
Posted: Thursday 28 January 2016 12:26
by epierre
Hello,
same issue here, to I converted to ppm/ppg and sent it to this ill named CO2.
what are you using to mesure gases ? My page here:
http://forum.mysensors.org/topic/147/air-quality-sensor
Re: airquality
Posted: Thursday 28 January 2016 19:36
by gizmocuz
Air quality is in PPM
Re: airquality
Posted: Thursday 28 January 2016 19:40
by epierre
right now yes, and still shows "CO2" in the axis sadly.
There are some formulae out there to go to ppm but some gases are in ppb (like the dangerous CO).
Re: airquality
Posted: Thursday 28 January 2016 19:43
by gizmocuz
And is that air quality ?
Re: airquality
Posted: Thursday 28 January 2016 19:48
by epierre
Air quality
https://en.wikipedia.org/wiki/Air_quality_index by definition is a combination of all this (see how to compute):
O3 (ppb) O3 (ppb) PM2.5 (µg/m3) PM10 (µg/m3) CO (ppm) SO2 (ppb) NO2 (ppb)
so sorry not only ppm

Re: airquality
Posted: Thursday 28 January 2016 20:13
by htca
Actually, I get all my parameters in μg/m3, last readings:
NO2 50
NO 9
O3 27
PM10 16
PM25 7
C6H6 1
C7H8 0
SO2 3
So if there is a unit conversion to ppb.... Please point me to it (but it has a relation with temperature and airpressure I guess).
Re: airquality
Posted: Thursday 28 January 2016 20:14
by htca
I get my data from a public source on the internet.
Re: airquality
Posted: Thursday 28 January 2016 21:25
by epierre
htca wrote:
I get my data from a public source on the internet.
huh I am interrested by that source for I haven't found a decent SO2 sensor yet, only fakes...
Re: airquality
Posted: Thursday 28 January 2016 21:35
by epierre
htca wrote:Actually, I get all my parameters in μg/m3, last readings:
NO2 50
NO 9
O3 27
PM10 16
PM25 7
C6H6 1
C7H8 0
SO2 3
So if there is a unit conversion to ppb.... Please point me to it (but it has a relation with temperature and airpressure I guess).
http://www.lenntech.com/calculators/ppm ... illion.htm
some common gases are listed, else you would need their molecular weight
Re: airquality
Posted: Thursday 28 January 2016 22:58
by htca
epierre wrote:htca wrote:
I get my data from a public source on the internet.
huh I am interrested by that source for I haven't found a decent SO2 sensor yet, only fakes...
It is in the Netherlands:
www.luchtmeetnet.nl
Re: airquality
Posted: Thursday 28 January 2016 23:04
by htca
Anyway, I would appreciate if I could use some dummy parameter, so which one should I use?
Re: airquality
Posted: Friday 29 January 2016 16:17
by epierre
you have the most common CO CO2 O3 SO2... should be a good start
Re: airquality
Posted: Tuesday 02 February 2016 14:04
by epierre
the above gives these values:
NH3 17.03 g/mol
CO2 44.01
CO 28.01
H2S 34.08
NO2 46.01
NO 30.01
O3 48.00
C6H6 78.11
C7H8 92.14
you have:
NO2 50 μg/m3 gives 26,5868821 ppm
O3 27 μg/m3 = 0.027 mg/m3 -> (8,31441*298,15)/(48*101,325)*27=13,7617025 ppm
correct me if I'm wrong