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1. Introduction
The CSAT3BH is a heated version of the CSAT3B 3-D sonic anemometer with integrated
electronics. This instrument measures sonic temperature and wind speed in three dimensions.
The ultrasonic transducers, chassis, and strut can be heated to keep ice from accumulating on the
instrument. This new heating feature gives the CSAT3BH an advantage over traditional
anemometers and sonic anemometers because data loss will be significantly reduced in areas
that experience frozen precipitation. The CSAT3BH features variable power for the heating
elements by only delivering power to the heaters when needed, as opposed to the common
method of providing two-way heating (on or off). Further, real-time data flags are generated
when the heaters are turned on, which is critical to post-processing the data.
The CSAT3BH can measure average horizontal wind speed and direction, or turbulent
fluctuations of horizontal and vertical wind, and sonic temperature. Further, momentum flux and
sensible heat flux can be calculated from the turbulent wind and sonic temperature fluctuations.
Latent and sensible heat flux and gas fluxes may be determined by computing the covariance
between vertical wind measured by the CSAT3BH and scalar quantities measured by other
appropriate sensors.
Before attempting to use or install the CSAT3BH, please review:
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2. Precautions
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READ AND UNDERSTAND the
section at the back of this manual.
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CAUTION
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Voltage input must be within a range of 22 to 32 VDC for the CSAT3H heater
controller and 9.5 to 32 VDC into the power connector on the CSAT3BH electronics.
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The CSAT3BH head should be handled by holding the block at the back of the
sensor. Handling it by the arms or transducers could cause geometric deformation,
which degrades the measurements.
CSAT3BH Three-Dimensional Heated Sonic Anemometer
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