Campbell Scientific 27106T Gill Propeller Anemometer - Manual (Page 10)

27106T Gill Propeller Anemometer
TABLE 5-1. Wind Speed Multiplier
(With Configuration Code 21*)
Unit Multiplier
Miles per Hour 0.04025
Meters/Second 0.01800
Kilometers/Hour 0.06480
Knots 0.03496
*When the propeller is used for measuring the vertical wind component, users
may want to apply an additional multiplier of 1.25 to the output signal. This
may be done numerically in the data processing operations or electronically in
the signal conditioning. Using the additional multiplier brings the anemometer
output signal within ±3% of the cosine response for elevation angles between
-30° and +30°. Since the standard deviation of wind elevation angle in open
terrain rarely exceeds 12°, 98% (2.5 standard deviations) of observations will
be within ±30°. Using the multiplier is NOT necessary when the anemometer
is used in a UVW configuration with RM YOUNG model 26601UVW
Translator.
5.2 Example Programs
The following programs measure the 27106T every 1 second, and store the
maximum, minimum, and average wind speed every 10 minutes. Wiring for
the examples is given in Table 5-2.
TABLE 5-2. Wiring for Example Programs
Color Wire Label CR1000 CR10X
White Signal SE1 SE1
Black Signal Reference G
Clear Shield G
5.2.1 CR1000 Example Program
'CR1000 Series Datalogger
'Declare Public Variables
Public Batt_Volt
Public WS_ms
Units Batt_Volt=Volts
Units WS_ms=meters/second
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