WH-1080 "class ohlson" showing too low wind speed values

[Silli]

Hello.
Is there a custom firmware or way to modify the wind speed sensor to show higher values on main unit ? I am constantly getting 4-5 m/s too low gust speeds. Shoud I shorten cup rods ?

[AllyCat]

Shoud I shorten cup rods ?

Hi,

Very probably NO !

At what wind speed are gusts "constantly 4 - 5 m/s too low"? It can't be in a light breeze! How do you know?

Where (and at what height) is the anemometer sensor mounted? Have you checked that the sensor is generating two pulses per revolution?

Cheers, Alan.

[Silli]

Hi.
Sensor is mounted at top of pole 9 meters from ground.
Wind speed is checked against 2 diffrent portable meters. Vdo and one from hobbyking.
Ill check the sensor...at least its very sensitive rotating so its not bearings.

[beteljuice]

How long are the gusts ? (Actually there is a precise definition of a 'gust', but we won't bother with that !)
If they are short lived, they are not actually gusts.
I suspect that you are not comparing like-for-like as the sample periods are probably different.

... but I could be totally wrong

[AllyCat]

Hi,

But what percentage is the error (Fine Offset claim +/- 10% at higher windspeeds). Is there an error in the reported "average" windspeed?

Note that Fine Offset calculates their gust as a "two-second average" and I believe that the normal "meteorological" gust is defined over a period of 3 seconds (or is that just what Davis does?). The rotational inertia of the anemometer (cups) will (also) have some effect on the measured gust speed.

Cheers, Alan.

[Charlie]

Hello.
Is there a custom firmware or way to modify the wind speed sensor to show higher values on main unit ? I am constantly getting 4-5 m/s too low gust speeds. Shoud I shorten cup rods ?

It would be almost impossible to do that and maintain balance. Why not simply change the multiplier in the calibration section of Cumulus? That would do exactly the same thing...
At this point, you should be thinking -->

[Silli]

Hello.
Is there a custom firmware or way to modify the wind speed sensor to show higher values on main unit ? I am constantly getting 4-5 m/s too low gust speeds. Shoud I shorten cup rods ?

It would be almost impossible to do that and maintain balance. Why not simply change the multiplier in the calibration section of Cumulus? That would do exactly the same thing...
At this point, you should be thinking -->

Yes i do but only because I have waisted money to something that sits on my wall showing false readings.
I use my laptop to check the weather from local official station, not corrected values from cumulus lol.
Suprice suprice, outdoor humidity is also way off around 15 percent. Maybe I just expected too much for a low priced equipment....
1.23 seems to correct wind readings match the average readings from near airport.
Any suggestions to correct outdoor humidity readings ?

[Silli]

Hello.
Has anyone found a way to calibrate display readings indspeed and humidity ?