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Weather Station Hardware => Davis Instruments Weather Stations => Topic started by: mickopla on November 29, 2010, 06:29:43 AM
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If the Vue wasn't exactly level what readings would be affected by this??
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In theory...ALL readings COULD be skewed by an uneven ISS.....
The most sensitive would likely be the rain gauge......the tipping bucket really needs to be level to "tip"
when it measures each .01" of rain....
How high are you/have you mounted the ISS??
Mine's at 15' AGL....to level it, I took a small mirror and mounted it (temporarily...) to a snow rake, hen raised it up so I could see the bubble level and apply the needed tension to 3 nylon guy lines just under the ISS mount.
The key is being able to see the bubble level; if you install past ladder height, it's either guesswork....or improvise.....!
Good Luck!
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Yep, the rain gauge.
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Cheers guys, i was just wondering as the bubble is slightly off the middle but still in the circle and was thinking would this affect things that much. My ISS is 5 meters high but when i was installing it i used the mirror trick stuck to a long 2x2 length of timber to see if it was level. While i have you here guys can i ask you if a slight shake in very wind conditions in the mounting pole would hamper readings???
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any reason you couldnt put a level across the rain catcher? or has anybody tried that and compared it to the built in bubble? I recall a telescope tracking mount that has an internal bubble, people found that some were off and used their own, and the performance improved. 2 different applications but the bubbles can be wrong.
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While i have you here guys can i ask you if a slight shake in very wind conditions in the mounting pole would hamper readings???
Yes, it would slightly hamper rainfall readings, wind direction readings, and possibly wind velocity readings.
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In theory...ALL readings COULD be skewed by an uneven ISS.....
The most sensitive would likely be the rain gauge......the tipping bucket really needs to be level to "tip"
when it measures each .01" of rain....
How high are you/have you mounted the ISS??
Mine's at 15' AGL....to level it, I took a small mirror and mounted it (temporarily...) to a snow rake, hen raised it up so I could see the bubble level and apply the needed tension to 3 nylon guy lines just under the ISS mount.
The key is being able to see the bubble level; if you install past ladder height, it's either guesswork....or improvise.....!
Good Luck!
Which is why Davis recommends around 10 feet, start going over and your rain and temps, dew, point etc will be out, but wind would be more accurate. also for access and getting this level 10 feet is ideal.
I have mine at 10 feet, it's a good compromise, also don't need guide wires, and access is easy and see the bubble level.
The pole needs to be solidly in place as flex will give false rain readings, hence I have only gone 10 feet. Compared to other weather stations where I am, the wind direction and speed seem ok.
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I put mine at 5 metres for wind reasons as my house would block most Northerly or North East winds, but i think i might drop it lower as whats the point in having wind direction ok if everything else is wrong. You can see a video clip showing where its sited on my website www.waterfordcityweather.com. Its actually a nice clip i took last Saturday when it was snowing. Thanks for the advice.
Mike
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Nice clip - and it illustrates that you aren't getting correct wind direction in those conditions. For instance, around 12 seconds, the rapid reversal of the wind vane is probably due to the effect of surrounding buildings.
So, as you said, perhaps there is a better compromise location. You can't have everything.
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Nice clip - and it illustrates that you aren't getting correct wind direction in those conditions. For instance, around 12 seconds, the rapid reversal of the wind vane is probably due to the effect of surrounding buildings.
So, as you said, perhaps there is a better compromise location. You can't have everything.
Thanks for the feedback Dale. Glad you liked the clip.
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hey...you got drunks driving down the wrong side of the street! ;)
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The bubble in the level on my Vue disappeared after six months, so that is pretty useless. I now use a small spirit level across the top of the rain funnel.
Alan