Davis Instruments Cup Anemometer, Руководство пользователя

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2 ABOUT THE DAVIS CUP ANEMOMETER Anemometer
2 About the Davis Cup Anemometer
The anemometer enables you to measure and display wind-related
conditions such as wind speed and wind direction with your Em50
or Em50R logger.
2.1 Specifications
•
Wind Direction
Display Resolution: 16 points (22.5
◦
) on compass rose, 1
◦
in
digital display
Accuracy:
±
7
◦
•
Wind Speed
Range: 2 to 175 mph., 4 to 280 kph, 2 to 152 knots, 0.9 to 78
m
2 s
Accuracy:
±
5%
•
System Hardware Compatibility
Em50 Firmware version 1.19 or greater
ECH20 Utility 1.11 or greater
2.2 Integration with Em50
The Em50 measures the average wind direction in one minute in-
tervals. The value of the wind direction and number of pulse counts
(magnitude) are used to resolve the wind direction into X and Y vec-
tor components. The vector components from multiple one-minute
readings are summed together. The X and Y components are com-
bined to store the “dominant” or “weighted average” wind direction
for the measurement interval.
Note: When there is no wind, the vector math for direction will re-
solve to 0 (North) – regardless of the actual direction of the wind
vain.
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