help with site for VP2

[floggitt]

I have been using a fine offset station but it has out lived its usefulness! So a VP2 Plus will be replacing it. Currently the station is mounted on top of a grain silo. Access is easy by permanent ladder, mounting is easy to steel structure.

Excellent view of the horizon on all sides except to the north (so solar and UV sensors and read very well)

The height is equal to an adjoining barn so should I raise the anemometer above this?

Currently the ran gauge is useless at this height as we are very exposed and most of it blows back out of the sensor (bad design not helping)

The large cement fibre roof could raise the temp reading some too (if the wind is northerly and its sunny) so hoping the FARS will be able to correct this

The other option is on a south facing gable end of the bungalow, the wind reading would be disturbed by the large barn to the north. But I can use a cabled system (cheaper)



my back is to the south when taking this picture. Site 2 is above the sky dish on gable end

[steve]

The top of the silo looks like a good place for the anemometer, particularly if you can raise it 2 or 3 feet above it, but you need to get the ISS itself with the temperature sensor down to around 4ft from the ground. There's some useful information in a PDF from the Met Office here: http://www.rmets.org/sites/default/file ... -guide.pdf and on the FAQ site that I maintain here: http://weatherfaqs.org.uk/node/124

[floggitt]

Thanks for the links Steve I will have a look.
The problem being as you have said else where the solar and UV sensors will then also be at 4ft height and be covered by the shadows of large buildings. need to find a compromise some where

[steve]

A reasonable compromise might be to put it all up on the gable end of the house.

[floggitt]

I think I will try that first, however the photo is deceptive the house is a lot lower than the silo, but i can keep the fine offset up on the silo and see how much variation there is.

Or put the whole lot on the silo and get a remote temp sensor when funds allow, if this year is any thing to go by radiation effects will be minimal!

Fluctuation in temperature is less important to me than the wind and rain data I guess, the fine offset is badly effected by rain blowing off the collector how good is the VP at collecting rain accurately in windy conditions or will that require shielding if so exposed ?

Great site by the way Steve thank you I have set up the website and banner.php all from just reading your forum.

[steve]

the fine offset is badly effected by rain blowing off the collector how good is the VP at collecting rain accurately in windy conditions or will that require shielding if so exposed ?

The VP2 rain collector is vastly deeper than the FO, so won't be affected by rain blowing out of it, but of course wind speeds are higher up there so you would expect less rain to be collected.

[floggitt]

Was thinking I would be getting the new station for xmas, but the %?*^& fine weather offset, has thrown another I dont want to connect, even though it modified. And when it has connected the pressure is sky high, the temp is wrong, and it says we had 176mm of rain yesterday. Argghhhhhh.
so I have edited the data again, re calibrated again. But data had already been sent to underground, pws and wow websites sadly.

So I have got the credit card out and will be ordering a new station today

[floggitt]

VP2 Pro and data logger ordered, should be here end next week. At least all the software and websites are up and running so after setting up I only need to connect and change a few settings in cumulus and I should be running. Any tips welcomed.

Also can i easily generate an average daily wind run figure, or average daily wind speed for a set period, this would be useful for prospecting our site for a wind turbine.

[steve]

Also can i easily generate an average daily wind run figure

If you open a copy of dayfile.txt in Excel, then select the wind run column for the period you want, Excel will show you the total and average for the selected period. I imagine other spreadsheet software has the same facility.

[floggitt]

Also can i easily generate an average daily wind run figure

If you open a copy of dayfile.txt in Excel, then select the wind run column for the period you want, Excel will show you the total and average for the selected period. I imagine other spreadsheet software has the same facility.

Will give this a shot thanks

[steve]

The 'this period' display in Cumulus will also give you the total wind run for any given date range (from which you could calculate the average).

[floggitt]

Just got an email to say weather station has shipped. So I am just a bit excited should have it here before the weekend

[floggitt]

Still have fingers crossed to receive the new VP before the weekend, especially as the blink fine offset, has thrown another wobbly today. We had a 150mph wind 50mm/hr rain and it was -10 degrees. Cant be bothered to edit it all out yet again. So I will be dumping this years weather data and starting a fresh. And just to make me feel better I shall throw the dam thing from the top of the grain silo when I take it down and for good measure run over it with the John Deere as well

[floggitt]

The Vantage has been working great for a couple of days, very pleased with this system now. Yesterday we had very fine rain which was blowing horizontally and as predicted (steve) it did not register as raining as it was blowing straight over the collection bowl. It is sited up on top of the silo because it gives me easy access while I check how things are working. I think the long term plan will be to move it to the house gable end, and have the wind vane on the silo using a wireless connection.
The readings I am getting for temp pressure etc are comparable with a local airfield so all the calibration settings in cumulus are at their default values, which is a vast change from before.