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Wind Speed Testing

Discussion specific to Fine Offset and similar rebadged weather stations
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wd40
Posts: 448
Joined: Thu 05 Aug 2010 10:02 pm
Weather Station: WS2080
Operating System: W7
Location: GA, USA
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Wind Speed Testing

Post by wd40 »

I am planning on taking down my station mask to put in a larger one.

Would it be of any use to run a speed test on the sensor? Since I cannot measure wind speed it would only be a test to see what comes out of the station for anemometer spinning at a constant RPM.

Not sure how accurate it would be since the device I will measure RPM is from my R/C model airplane days.

Randy
serowe
Posts: 484
Joined: Tue 03 Aug 2010 6:23 am
Weather Station: WM918
Operating System: Win Server 2008 R2
Location: Ferntree Gully, VIC, Oz
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Re: Wind Speed Testing

Post by serowe »

If you know any maintenance companies who look after air conditioning, they *should* have a device which they use to measure air speed - usually about 3 inches square with a fan on the inside which is calibrated - not sure what they 'official' name for these devices is, but I have used them (many years ago!)

Might be worth asking around.
Punctuation is the difference between 'Let's eat, grandma' and 'Let's eat grandma'
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Ned
Posts: 258
Joined: Mon 19 Jul 2010 11:15 am
Weather Station: WS2083 (aspirated)
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Location: Auckland NZ

Re: Wind Speed Testing

Post by Ned »

I've still got an old mechanical airflow meter/anemometer from my days in air conditioning, but haven't bothered trying to test my WS.
You'd want an air flow of constant strength and direction (as from a fan) to compare the two instruments, as well as testing over a wide range of speeds. Not so easy to arrange, and the required calibration required across the range may well not be achievable with a simple correction factor.

If trying to check speed by calculation using the RPM of the vanes, I wonder where the effective radius of rotation would lie - at the centre of the cup?
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steve
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Re: Wind Speed Testing

Post by steve »

I remember someone once testing their station's anemometer by taking their station out in the car, with the anemometer attached, sticking the anemometer out of the window and comparing the reading on the console with the reading from a GPS :shock:
Steve
serowe
Posts: 484
Joined: Tue 03 Aug 2010 6:23 am
Weather Station: WM918
Operating System: Win Server 2008 R2
Location: Ferntree Gully, VIC, Oz
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Re: Wind Speed Testing

Post by serowe »

LOL maybe I can attach one to the car and use it if I get booked for speeding? (Forget about the 30 km/h tail wind that helps reuce the indicated speed though! 8-)
Punctuation is the difference between 'Let's eat, grandma' and 'Let's eat grandma'
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