18m Wind Vane
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The 18m Anemometer is mounted 18m above the ground on a met tower (Twr 4).

About the Wind Vane

The 18m Wind Vane is mounted 18m above the ground, on the same tower as the 18m Anemometer.

Wind direction, defined as the direction from which the wind is blowing, is measured by a wind vane mounted 18m above the ground on a met tower (Twr 4).  The instrument is comprised of a vane attached to a spindle which is connected to a potentiometer. Wind direction is measured via the potentiometer position.  The unit of measurement is degrees relative to True North, and is independent of the magnetic variation (the horizontal angular difference between True North and Magnetic North).

There are several characteristics of wind vanes; they give an instantaneous measurement while the wind direction is constantly changing; they do not work well at very low wind speeds and at near calm conditions can give totally false readings; and like anemometers the spindles can freeze up in very cold temperatures.

The manufacturer is Vector Instruments.

There are two sets of instruments, but one is dedicated to an adjacent experimental setup.