Welcome to the Cumulus Support forum.

Latest Cumulus MX release 3.9.1 (build 3096) - 31 October 2020 (please see announcement regarding releases since 3.5.0)
Legacy Cumulus 1 release v1.9.4 (build 1099) - 28 November 2014 (a patch is available for 1.9.4 build 1099 that extends the date range of the NOAA report and Snow Index drop-down menus to 2030)

Use this Wiki link to Download the Software (Cumulus MX / Cumulus 1 and other related items).

Sensor PM 2.5 & PM 10 - Purpleair Network www.purpleair.com

From build 3044 the development baton passed to Mark Crossley. Mark has been responsible for all the Builds since. He has made the code available on GitHub. It is Mark's hope that others will join in this development, but at the very least he welcomes your ideas for future developments (see Cumulus MX Development suggestions).

Moderator: mcrossley

User avatar
HansR
Posts: 1439
Joined: Sat 20 Oct 2012 6:53 am
Weather Station: Davis Vantage Pro 2+
Operating System: Raspbian GNU/Linux 10 (Buster)
Location: Wagenborgen (NL)
Contact:

Re: Sensor PM 2.5 & PM 10 - Purpleair Network www.purpleair.com

Post by HansR »

https://meteo-wagenborgen.nl / Cumulus 3.8.4 (build: 3094)
Davis Vantage Pro 2+ / Raspberry Pi 3 Model B Plus Rev 1.3
Raspbian Buster / 5.4.51-v7+ armv7l
Mono JIT compiler version 6.12.0.90 (tarball Fri Sep 4 14:21:54 UTC 2020)

User avatar
beteljuice
Posts: 3028
Joined: Tue 09 Dec 2008 1:37 pm
Weather Station: None !
Operating System: W10 - Threadripper 16core, etc
Location: Dudley, West Midlands, UK

Re: Sensor PM 2.5 & PM 10 - Purpleair Network www.purpleair.com

Post by beteljuice »

Hans .....

The answer's 42, you must understand the question first
Image
......................Imagine, what you will KNOW tomorrow !

User avatar
HansR
Posts: 1439
Joined: Sat 20 Oct 2012 6:53 am
Weather Station: Davis Vantage Pro 2+
Operating System: Raspbian GNU/Linux 10 (Buster)
Location: Wagenborgen (NL)
Contact:

Re: Sensor PM 2.5 & PM 10 - Purpleair Network www.purpleair.com

Post by HansR »

beteljuice wrote:
Sun 18 Oct 2020 12:27 am
Hans .....

The answer's 42, you must understand the question first
Ah, that's what you get when using the word hitchhiking I Guess :lol:
But indeed, I assumed you ment something else... Assume :bash:

So, yes I guess everywhere most people like ready cooked meals.
But there are always some who try the real work. Search different routes, other answers. Truth.
Ah well it's a large galaxy.
https://meteo-wagenborgen.nl / Cumulus 3.8.4 (build: 3094)
Davis Vantage Pro 2+ / Raspberry Pi 3 Model B Plus Rev 1.3
Raspbian Buster / 5.4.51-v7+ armv7l
Mono JIT compiler version 6.12.0.90 (tarball Fri Sep 4 14:21:54 UTC 2020)

User avatar
HansR
Posts: 1439
Joined: Sat 20 Oct 2012 6:53 am
Weather Station: Davis Vantage Pro 2+
Operating System: Raspbian GNU/Linux 10 (Buster)
Location: Wagenborgen (NL)
Contact:

Re: Sensor PM 2.5 & PM 10 - Purpleair Network www.purpleair.com

Post by HansR »

For those interested in this American 'correction' of actual measurements into 'corrected' (read reduced) values of particle matters sensor output.
Some additional articles (I may update this post if I find more interesting things)
  1. An updated version (dated April 21, 2020) of the article that really got me going (posted above by ConligWX). Final publication targeted for summer 2020 but did not find it. The original poster article is undated. The two correction equations differ a lot.
  2. An article on deeper understanding of the effect of the corrections (reduction of the nowcast values)
  3. Note that the correction discussed is only for the PurpleAir device because that one has two sensors read alternately on a ten second frequency (so each is reach once every 20 seconds). The average of the two is in the equation with a procedure how to handle differences.
  4. Some EPA (from the USA that is) info on indoor air quality. Really, breathing/living is a dangerous activity is my impression.
  5. LRAPA sponsoring the PurpleAir sensors (and corrections)
Well, to summarise: it has been made very complex and the aim seems to be to reduce the values presented (both concentrations and AQI).

Of course, everybody, any country, has the right to demand any data manipulation it wants. No problem with that. The point is, should USA EPA corrections be published alongside EU or UK rules? What would the effect be if nowcast and its (per device!) corrections become the new 'normal' while not a UK, EU or AUS demand.

Btw: the correction is applied by PurpleAir on their website, so not in the devices (the default being no correction). That is important as well if you want to emulate the PA device ;)
https://meteo-wagenborgen.nl / Cumulus 3.8.4 (build: 3094)
Davis Vantage Pro 2+ / Raspberry Pi 3 Model B Plus Rev 1.3
Raspbian Buster / 5.4.51-v7+ armv7l
Mono JIT compiler version 6.12.0.90 (tarball Fri Sep 4 14:21:54 UTC 2020)

andrea_iw2ntf
Posts: 7
Joined: Fri 17 Aug 2018 8:11 pm
Weather Station: Davis VP2 Plus
Operating System: Raspbian on Raspberry
Location: Gaggiano - MI - ITA
Contact:

Re: Sensor PM 2.5 & PM 10 - Purpleair Network www.purpleair.com

Post by andrea_iw2ntf »

Thank you!

I see that it is working.

I can provide my sample file.

http://www.fracassi.net/public/json_31569.txt

this link was copied from the purpleair website.

or, the sensor is in the same LAN, you can access it directly.

Unfortunately I am very impractical!

Post Reply