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Cables for the CSAT3BH, although not included in the standard package, are specified at the time
of order and are shipped with the CSAT3BH:
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CSAT3HCBL3-L
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RS-485 cable (either CSAT3HCBL1-L or CSAT3HCBL2)
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Either CSAT3BCBL1-L or CSAT3BCBL2-L and CSAT3BCBL3-L
4. Overview
The CSAT3BH is an ultrasonic anemometer for measuring sonic temperature and wind speed in
three dimensions. It is often used for studies of turbulence and flux measurements, where
turbulent fluctuations of wind speed and sonic temperature must be measured at high
frequencies (at 10 Hz, for example).
From the turbulent wind fluctuations, momentum flux can be calculated. The covariance of
vertical wind and sonic temperature yields sonic sensible heat flux. By finding the covariance
between vertical wind and scalar measurements made by other fast-response sensors, such as
fine-wire thermocouples or gas analyzers, other fluxes can be calculated. For example, sensible
and latent heat fluxes, carbon dioxide flux, and other trace gas fluxes can all be measured by
combining the CSAT3BH with other sensors.
The CSAT3BH can communicate measurements using SDM (Synchronous Device for
Measurements), USB, RS-485, and CPI (CAN Peripheral Interface) communications. For optimal
synchronization with other fast-response sensors for applications such as eddy covariance,
Campbell Scientific recommends using SDM or CPI communications with an appropriate
Campbell Scientific data logger.
The CSAT3BH is a heated version of the CSAT3B, with the same measurement specifications.
Developed for use in cold environments that typically experience ice buildup on sensors, the
CSAT3BH is designed to prevent ice from accumulating on the sensor in order to avoid
prolonged periods of data loss.
The CSAT3BH is paired with a temperature and relative humidity probe that is used to determine
when the heaters need to be operating. The information from the temperature and relative
humidity probe is processed within the CSAT3H heater controller box, dictating operation of the
heaters. Additionally, temperature measurements are made throughout the body of the sonic
anemometer to determine the temperature change of the sensor as a result of the heaters. This
information is delivered to the controller box as well.
CSAT3BH Three-Dimensional Heated Sonic Anemometer
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