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Eclipse SmartHome™ project
https://www.eclipse.org/smarthome/
Eclipse Public License 2.0
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Missing Beaufort unit #5504

Closed lolodomo closed 6 years ago

lolodomo commented 6 years ago

Beaufort is missing as unit for the wind speed.

wborn commented 6 years ago

We discussed adding it in https://github.com/openhab/openhab2-addons/pull/3497. It's not really a unit but a scale.

lolodomo commented 6 years ago

We might be not able to handle an entry speed in Beaufort and then convert it in km/h but we should certainly be able to display a wind speed in Beaufort when the entry value is in km/h.

Is it impossible to have a one direction conversion ?

I think the user should be able to use "Bft" as unit in iutem/sitemap. I remember this was asked by a user for the WU weather binding in the forum. Note that the netatmo app is able to display values in Beaufort while the API is providing the speed in km/h.

wborn commented 6 years ago

Is it impossible to have a one direction conversion ?

It's a scale with a lot of history and some peculiarities.

See also "Conversion Of Anemometer Winds To Beaufort Numbers" on page 24 of this PDF.

Peculiarity:

If velocities expressed in m/s are used to determine the Beaufort wind force, the result sometimes differs from the wind force when the equivalent value expressed in knots or miles per hour was used.

kaikreuzer commented 6 years ago

I agree with @wborn that this won't work as a unit - I'd recommend that users use the scale transformation instead.