Campbell 05103, Руководство пользователя

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05103, 05103-45, 05106, 015108, 05108-45 and 05305 R.M. Young Wind Monitors
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Table 7-2. Wind Speed Multiplier
Model Miles/
Hour Output Metres/
Second Output
05103, 05103-45, or 05106 0.2192 0.0980
05108 or 05108-45 0.3726 0.1666
05305 0.2290 0.1024
7.4.2 Wind Direction
The wind vane is coupled to a 10 k

potentiometer, which has a 5 degree
electrical dead band between 355 and 360 degrees. A 1 M

resistor between the
signal and ground pulls the signal to 0 mV (0 degrees) when wind direction is
between 355 and 360 degrees.
The CR200(X) datalogger uses the ExDelSE() instruction to measure wind
direction. All other CRBasic dataloggers use the BRHalf() instruction. Edlog
dataloggers (CR510, CR10X, CR23X) use Edlog Instruction 4—Excite, Delay
(P4).
Some CRBasic measurement sequences cause the measurement of the wind
direction to return a negative wind direction (–30
º
) while in the dead band. This
can be overcome by using a delay of 40 ms (40,000µs) or by setting negative wind
direction values to 0.0: If WindDir < 0, then WindDir = 0.0.
The excitation voltage, range codes, and multipliers for the different datalogger
types are listed in Table 7-3. Appendix B has additional information on the P4
and
BRHalf() measurement instructions.
Table 7-3. Parameters for Wind Direction
CR200(X)
CR300
Series
CR800,
CR850,
CR1000
CR1000X CR6
CR5000,
CR3000
Measurement
Range
NA mV 2500 mV 2500 mV 5000 mV 5000 mV 5000
Excitation
Voltage
2500 mV 2500 mV 2500 mV 2500 mV 2500 mV 5000 mV
Reverse
Excitation
NA NA True True True True
Delay or
Settling Time
20000 µs 20000 µs 20000 µs 20000 µs 20000 µs 20000 µs
Multiplier 0.142 355 355 355 355 355
Offset 0 0 0 0 0 0
7.4.3 Wind Vector Processing Instruction
The Wind Vector output instruction is used to process and store mean wind speed,
unit vector mean wind direction, and Standard Deviation of the wind direction
(optional) using the measured wind speed and direction samples.