So, the particle counts are particles / 0.1 liter. Multiply by 10,000 to get particles / meter^3
What about the "concentration units"? I assume that's ug/meter^3...
but what's the difference between "standard" and "environmental"?
-thanks....
PM2.5 Air quality Sensor - Units?
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- amhamilton
- Posts: 2
- Joined: Mon Jun 04, 2018 7:13 pm
Re: PM2.5 Air quality Sensor - Units?
I was hoping for an answer to this same problem. Did you ever find an answer?
- solaria123
- Posts: 13
- Joined: Mon Jan 09, 2017 4:07 pm
Re: PM2.5 Air quality Sensor - Units?
Nope.
I discovered that it can't actually detect particles > 3um; the numbers it reports are just estimates:
For my application, using the 0.5 micron counts. When the count exceeds 352, the ESP8266 triggers the HVAC to filter the air...
I discovered that it can't actually detect particles > 3um; the numbers it reports are just estimates:
...but nothing about the Concentration Units. Maybe it has something to do with how it estimates the large particle distribution? Standard vs Environmental particle spectrum?From these measurements, we conclude that the Plantower PMS5003 is able to measure PM2.5 more
or less correct. With a suitable calibration, it may be calibrated to a reference instrument such as the
Grimm. The PMS5003 however is not able at all to directly measure large particles > 3um. When it
outputs PM10 values, these are pure estimates based on particle sizes it can measure (d < 3um) and
under the assumption of a broadly distributed particle spectrum. When the particle spectrum is not
containing PM mass contributions at sizes < 3um, the PMS5003 erroneously outputs PM10 values close
to zero.
These findings intensify the strong suspicion that low-cost PM-sensors, mainly produced by Chinese
manufacturers and designated as PM2.5 sensors but also reporting PM10 values, aren’t able to
measure particles larger than 3um and therefore solely extrapolate on PM10 values assuming a certain
particle distribution.
https://www.researchgate.net/publicatio ... _PM-sensor
For my application, using the 0.5 micron counts. When the count exceeds 352, the ESP8266 triggers the HVAC to filter the air...
- adafruit_support_carter
- Posts: 30785
- Joined: Tue Nov 29, 2016 2:45 pm
Re: PM2.5 Air quality Sensor - Units?
Check out the info I posted to @amhamilton's similar question here:
viewtopic.php?f=48&t=136528#p676664
viewtopic.php?f=48&t=136528#p676664
Please be positive and constructive with your questions and comments.