Campbell CSAT3B, Instruction Manual, Page: 53 / 88

CSAT3B Three-Dimensional Sonic Anemometer
TABLE 7-3. CSAT3B Cable Wire Assignments
CSAT3B
Cable Type Signal Description Pigtail Color
Connector
Pin #
CSAT3BCBL1
Power 9.5-32 Vdc Red 1
Ground Black 2
SDM GND Brown 3
SDM C1 White 4
SDM C2 Yellow 5
SDM C3 Blue 6
Shield Clear Shell
CSAT3BCBL2
Power 9.5-32 Vdc Red 1
Ground Black 2
CSAT3BCBL3
RxA Brown 4
RxB Brown stripe 2
TxA Blue 6
TxB Blue stripe 1
RGND Green 5
If a fine-wire thermocouple such as a model FW05 with FWC-L is being used,
the wiring designations in TABLE 7-4 should be followed to connect the
thermocouple to a differential voltage channel on a datalogger.
TABLE 7-4. FW05/FWC-L
Fine-Wire Thermocouple
Description Color
Signal high Purple
Signal low Red
8. Operation
8.1 Theory of Operation
The CSAT3B uses three pairs of non-orthogonally oriented transducers that
transmit and receive ultrasonic signals. The time of flight of a sonic signal
between a pair of transducers is directly related to the wind vector component
that is parallel to the sonic axis. The CSAT3B is able to calculate the wind
vector components along each sonic axis using the time difference between an
outgoing and return sonic signal, along with the distance between sonic
transducers. Trigonometric relationships are used to calculate the wind speed
in an orthogonal x-y-z coordinate system.
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