Author Topic: Wind Vane Sensitivity  (Read 10760 times)

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Offline sfabre1963

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Re: Wind Vane Sensitivity
« Reply #25 on: February 19, 2016, 12:45:09 AM »
Going to try the washer trick.  Anything in the 1-5 mph range is drawing dots all over the place, and this is a normal wind speed.  Yes I do think
this thing was engineered way to sensitive !!!

Offline DoctorKnow

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Re: Wind Vane Sensitivity
« Reply #26 on: February 19, 2016, 03:13:29 PM »
I'm getting ready to locate my sensor on the rooftop, further away from large trees. It will be the best possible location for wind there is. I need to take it down to check the batteries since it's been well over a year for those anyway, and I figured now that I have the chance to try the roof I would give that a shot.

Offline daman

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Re: Wind Vane Sensitivity
« Reply #27 on: February 19, 2016, 03:25:12 PM »
Eliminating wind shadows will help, my 5n1 shows nice strait wind direction dots on WU until the wind shifts to the south then there all over the place, I have buildings on the south side of my home making all sorts of wind drafts then I start seeing the wind vain swinging terribly.

get it up high so it has a clear shot to unobstructed wind from all directions and one would be fine.
KMIBADAX38
AcuRite Iris/AcuRite Access

Offline nincehelser

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Re: Wind Vane Sensitivity
« Reply #28 on: February 19, 2016, 04:26:19 PM »
Going to try the washer trick.  Anything in the 1-5 mph range is drawing dots all over the place, and this is a normal wind speed.  Yes I do think
this thing was engineered way to sensitive !!!

Turbulence due to objects around you aren't the only cause.

Light winds are often variable in direction.  That's why the term is often used in weather reports.

Good explanation of why that is here: http://www.theweatherprediction.com/habyhints/157/

Offline aweatherguy

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Re: Wind Vane Sensitivity
« Reply #29 on: February 20, 2016, 03:25:32 AM »
I tend to agree with nincehelser on this. In my experience, wind data is inherently very noisy, even in nearly calm conditions. Your noisy data is not necessarily an indication of a problem with the wind vane. That's not to say there isn't a problem...but the noisy data does not by itself prove the existence of a problem.

You might check to see if the vane is balanced. Try holding the 5n1 sensor horizontal (90 degrees from the normal mounting orientation). If the vane tends to spin around to the same orientation after you move it, then it's not balanced. The thing is that I am not 100% certain that it should be balanced. But if it is not balanced and that's intentional, then the wind vane shaft must be mounted perfectly vertical -- tilt it and you will have problems.

Perhaps there are some wind vane experts here that know if it should be perfectly balanced? My 5n1 is NOT perfectly balanced and will spin around to "vane down" if held horizontally.

The only other thing I can offer is an observation that wind vane design is far from trivial. If you want to get a sense of what's involved, have a gander at this paper which looks at some of the technical aspects involved.

http://journals.ametsoc.org/doi/pdf/10.1175/1520-0450%281967%29006%3C1114%3AEADOWV%3E2.0.CO%3B2

« Last Edit: February 20, 2016, 03:28:16 AM by aweatherguy »

Offline DoctorKnow

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Re: Wind Vane Sensitivity
« Reply #30 on: February 20, 2016, 12:12:43 PM »
Mine is on the roof now, and a good 85 ft from the nearest tall tree. It is actually easier for me to work on up there. I put the original wind spoons back on since I noticed the ones I made were just slightly out of balance, and made sure the ball bearings were free. I believe this was my problem was they kept seizing due to water intrusion due to cheap plastic... I shot some wd-40 type lube in there to get rid of the water and that has freed it up nicely.

Offline rpaulmanning

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Re: Wind Vane Sensitivity
« Reply #31 on: November 05, 2016, 12:27:16 PM »
I had precisely this issue with my Acurite 5-in-1 but managed to damp down the "spinning" issue by gluing the body of a metal pen over the front of the wind vane, adding weight but retaining the same profile. The vane still moves freely, however the constant spinning has certainly been reduced.  Hope this is helpful!

On Wunderground, rather irritatingly, 0 kph "wind speed" still records a direction, and these readings are from the Acurite Bridge so I'm not aware I can make any adjustment to these readings.  Here is my Wunderground website for info:

 https://www.wunderground.com/personal-weather-station/dashboard?ID=IANDALUC226#history

Offline TD22057

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Re: Wind Vane Sensitivity
« Reply #32 on: November 11, 2016, 10:46:16 PM »
If you don't mind a custom software solution, a moving vector average of the wind direction of the data works pretty well to smooth things out.  The algorithm can be found here:  http://www.webmet.com/met_monitoring/622.html

I have a raspberry pi intercept the bridge posts and turn them into MQTT messages.  Another process reads those, does a moving window average for all the data (including the wind vector direction average) and upload that to weather underground.  If you're interested, you can find the code here: https://github.com/TD22057/T-Home/

Offline BeaverMeadow

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Re: Wind Vane Sensitivity
« Reply #33 on: September 22, 2017, 12:58:47 PM »
"If you feel you have "dots all over the place", you can simply deaden the response, either physically or through software."


I'd like to deaden the response of the "all over the place" directional readings on my 5 in 1 unit. Could you please explain how I can do this with the Acurite software?

Thanks!
« Last Edit: September 22, 2017, 01:02:08 PM by BeaverMeadow »

Offline nincehelser

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Re: Wind Vane Sensitivity
« Reply #34 on: September 22, 2017, 01:13:56 PM »
"If you feel you have "dots all over the place", you can simply deaden the response, either physically or through software."


I'd like to deaden the response of the "all over the place" directional readings on my 5 in 1 unit. Could you please explain how I can do this with the Acurite software?

Thanks!

Acurite software doesn't have that feature.  You would have to use 3rd party software or write your own.