User`s guide

Chapter 5 _______________________________________ Serial Communication and Analog Output
VAISALA _______________________________________________________________________ 67
Table 15 below and Table 16 below list the most common settings for
different units.
Table 15 Common Transfer Function Settings for AOUT1 (WS)
Output Signal Scaling/ Units Setting for Gain Setting for Offset
Voltage 8 mV / mph
100 mV / m/s
0.01789
0.1
0
0
Current 0.2 mA / m/s 0.0002 0
Frequency 5 Hz / mph
10 Hz / m/s
11.18
10
-
WS425 - voltage 8 mV / mph 0.01789 0
WS425 - frequency 5 Hz / mph 11.18 -
Table 16 Common Transfer Function Settings for AOUT2 (WD)
Output Signal Scaling/ Units Setting for Gain Setting for Offset
Voltage 4 mV / °
20 mV /°
0.004
0.02
0
0
Current 50 uA / degree 0.00005 0
Potentiometer 359 ° = Aout ref 0.00278 0
You can configure output scaling or transfer function settings in a variety
of ways by changing the custom gain and offset. The basic measurement
units are m/s and degrees. The physical output units are V, A and Hz. For
the potentiometer, an output of 1 means 100 % of the Aout ref voltage.
The following formula illustrates the impact of gain and offset values on
the produced output:
o=y0 + k×s
where
o = Produced analog output (V, A, Hz, 100 %)
s = Measured wind direction or speed (in m/s or °).
k = Selected gain value.
y0 = Selected offset value. In frequency mode this value is 0.