cloudy cloudy

Author Topic: wmr200 problem with uvn800  (Read 197 times)

0 Members and 1 Guest are viewing this topic.

Offline s52sk

  • Posts: 24
  • Slovenia Europe
  • OS/Browser:
  • Win 7/Srvr 2008R2
  • Firefox 63.0
    • my weather station
wmr200 problem with uvn800
« on: December 05, 2018, 02:09:00 PM »
Hi i did not read all the post below that way sorry.
I have wmr200 and brand new  uvn800 sensor. I am put the sensor on my tower and fix him in direction 30 degrees in south position because i live in Slovenia and the sun is just about 30 degree over the horizon. The console applayed the UV sensor and i can see readings 3 UV. It was sunny day, today. All OK until  arriwed some clouds and after that UV drops imidietly to "zero"  when clouds go away the UV sensor come active to position 2 UV readings, but just that long until another cloud arriwed.
Now I don know i missed something but clouds could not disabled UV light, or am I missing in the school  this part... hehe. Can anyone explain what is going on with my UV sensor. I just hope i have all put correct in solar panel of WD.

Marco
« Last Edit: December 05, 2018, 02:12:45 PM by s52sk »

Offline niko

  • syzygy
  • Global Moderator
  • Posts: 27,666
  • Crystal Ball broken! Please post the URL.
  • Northern California, U.S.A.
  • OS/Browser:
  • Win 7/Srvr 2008R2
  • Chrome 70.0.3538.110
Re: wmr200 problem with uvn800
« Reply #1 on: December 05, 2018, 02:48:39 PM »
Clouds do block UV, nothing wrong.

Offline s52sk

  • Posts: 24
  • Slovenia Europe
  • OS/Browser:
  • Win 7/Srvr 2008R2
  • Firefox 63.0
    • my weather station
Re: wmr200 problem with uvn800
« Reply #2 on: December 05, 2018, 04:01:41 PM »
Ok Niko thanks, for explanation.

Marco

Offline bitsostring

  • Posts: 506
  • Oregon Scientific WMR200
  • Edinburgh, UK
  • OS/Browser:
  • Win NT 10.0
  • Chrome 64.0.3282.140
Re: wmr200 problem with uvn800
« Reply #3 on: December 05, 2018, 04:40:57 PM »
I am put the sensor on my tower and fix him in direction 30 degrees in south position

There is no need to point the sensor in any particular compass direction. It should be upright and "facing the indoor console" for best signal, according to Oregon Scientific.
It's meant to be fun. . .

Offline niko

  • syzygy
  • Global Moderator
  • Posts: 27,666
  • Crystal Ball broken! Please post the URL.
  • Northern California, U.S.A.
  • OS/Browser:
  • Win 7/Srvr 2008R2
  • Chrome 70.0.3538.110
Re: wmr200 problem with uvn800
« Reply #4 on: December 05, 2018, 05:47:24 PM »
There is no need to point the sensor in any particular compass direction. It should be upright and "facing the indoor console" for best signal, according to Oregon Scientific.

A problem with most consumer wx station UV sensors is that they don't cover the whole sky very well*. When sun angles are low in the winter the user is very tempted to point them somewhere other than vertical in order to get any meaningful reading  :(

* Davis UV has the correct cosine response, but costs more than many consumer stations.

Offline bitsostring

  • Posts: 506
  • Oregon Scientific WMR200
  • Edinburgh, UK
  • OS/Browser:
  • Win NT 10.0
  • Chrome 64.0.3282.140
Re: wmr200 problem with uvn800
« Reply #5 on: December 05, 2018, 08:02:04 PM »
A problem with most consumer wx station UV sensors is that they don't cover the whole sky very well.

I'm pretty happy with my UVN800, even if it might be reading a tad high. First two attachments show OS UV (integer values) and Davis solar for 28 June 2018, a cloudless day, as recorded on WU by me and a neighbour about half-a-mile away respectively (his solar sensor is in shadow until 0845).

Next two show "cloud enhancement" on a day with "fair-weather" cloud. Expected max values here are UV=8 and solar=850 W/m. (I have registered 13. . .)

Quote
When sun angles are low in the winter the user is very tempted to point them somewhere other than vertical in order to get any meaningful reading.

Here at 56N I don't register UV at all from November through February. Just as long as the console shows 0 (and not --) I know it's still working  :D


« Last Edit: December 07, 2018, 03:17:04 PM by bitsostring »
It's meant to be fun. . .

Offline niko

  • syzygy
  • Global Moderator
  • Posts: 27,666
  • Crystal Ball broken! Please post the URL.
  • Northern California, U.S.A.
  • OS/Browser:
  • Win 7/Srvr 2008R2
  • Chrome 70.0.3538.110
Re: wmr200 problem with uvn800
« Reply #6 on: December 06, 2018, 12:21:34 AM »
Mmmm, your uvn800 is working very well  :)  The first two do show its peakier spatial response vs the cosine response of the solar sensor.

Offline s52sk

  • Posts: 24
  • Slovenia Europe
  • OS/Browser:
  • Win NT 10.0
  • Chrome 70.0.3538.110
    • my weather station
Re: wmr200 problem with uvn800
« Reply #7 on: December 06, 2018, 10:59:20 AM »
Maybe stupid question, but what will happened if I put UVN800 sensor in Jar?

Marco

Offline niko

  • syzygy
  • Global Moderator
  • Posts: 27,666
  • Crystal Ball broken! Please post the URL.
  • Northern California, U.S.A.
  • OS/Browser:
  • Win 7/Srvr 2008R2
  • Chrome 70.0.3538.110
Re: wmr200 problem with uvn800
« Reply #8 on: December 06, 2018, 02:37:00 PM »
Quote
Standard window glass, according to the International Ultraviolet Association, will allow UV-A to pass through while almost 100% of the UV-B and UV-C light is blocked.

Depends on the exact type of glass but the UV reading will be reduced to a greater or lesser extent.

Offline bitsostring

  • Posts: 506
  • Oregon Scientific WMR200
  • Edinburgh, UK
  • OS/Browser:
  • Win NT 10.0
  • Chrome 64.0.3282.140
Re: wmr200 problem with uvn800
« Reply #9 on: December 06, 2018, 08:07:43 PM »
Maybe stupid question, but what will happened if I put UVN800 sensor in Jar?

You would not be able to compare your readings with anyone else's. . . which is the whole point. They would be meaningless.
It's meant to be fun. . .