Delta OHM HD32MT.3, Руководство по эксплуатации

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HD32MT.3
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V1.2
Unweighted vector average
The unweighted vector average is a calculation method of the mean direction that allows to solve
the above mentioned problem of wrong calculation when the wind slightly changes direction
around the North.
The method provides the direction of the average versor (vector with unit magnitude) obtained
from measurements of wind direction.
The average is called "unweighted" because it does not take into account the intensity of the wind
in various directions, so it does not provide an indication about the direction in which the wind has
blown with greater intensity.
Fig. 7.2: versors average
The unweighted vector average is calculated by the data logger HD32MT3 on the basis of the di-
rection measurements of the wind vane (the average is the measure of index 50) or anemometer
HD52.3D ... (the average is the measure of index 53).
Vector average
The average vector calculates the mean vector of the speed and therefore requires the measure-
ment of both the direction and the speed (intensity) of the wind. The average direction and speed
calculated are respectively the direction and magnitude of the average vector.
The characteristic of the average vector direction is to be a weighted average, which takes into ac-
count the intensity of the wind in different directions and therefore provides an indication of the di-
rection in which the wind has blown with greater intensity.
Fig. 7.3: vector average
The average vector is calculated by the data logger HD32MT3 on the basis of measures of speed
and direction provided by the vane and by the cup anemometer (the averages are the measures of
index 51 and 52) or by the anemometer HD52.3D... (the averages are the measures of index 54
and 55).
If you are using an anemometer of the series HD52.3D…, you can get the vector average calculat-
ed directly from the anemometer at a configurable interval from 1 to 9 seconds, recording the
measures of index 17 and 18 and configuring the anemometer to use the vector method for the
calculation of the average (this is the default method, see the manual HD52.3D ...).