HD52.3D
- 23 -
V1.11
N
OTE
3
:
W
IND SPEED THRESHOLD VALUE
If the wind speed is very low, the determination of the direction can result inaccurate. The in-
strument allows to set the threshold value of speed below which the direction value is frozen
on the last acquired value.
N
OTE
4
:
W
IND DIRECTION EXTENDED CHARACTERISTIC
With 0÷359.9° wind direction measuring range, the analog output continues to oscillate be-
tween maximum and minimum scale if the direction continues to slightly fluctuate around 0°:
This effect can be reduced through the extended ("wrap-around") characteristic of wind direc-
tion. In this mode, the wind direction is considered as corresponding to 0÷539.9° range in-
stead of 0÷359.9°. The wide output fluctuation occurs the first time that the wind direction
goes from 0 to 359.9°; if later the “physical” direction goes back to 0°, the analog output will
always remain around 360°. Using the extended characteristic, the behavior of the above
graph changes into the following:
If 539.9° value is exceeded in extended mode, the output goes to the value corresponding to
180°.
The table below shows the correspondence between the value of the analog output and the di-
rection of the wind in the two modes.
4…20mA output
0…1V output
0…5V output
0…10V output
Wind
direction
standard extended standard extended standard extended standard extended
0° 4.00 4.00 0.00 0.00 0.00 0.00 0.00 0.00
180° 12.00 9.33 0.50 0.33 2.50 1.67 5.00 3.33
360° 20.00
14.67 1.00 0.67 5.00 3.33 10.00 6.67
540° -- 20.00 -- 1.00 -- 5.00 -- 10.00
Summary of Contents for HD52.3D... series
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