CSAT3B Three-Dimensional Sonic Anemometer
34
appropriately power all sensors and avoid excess attenuation of signals. The
following sections describe different types of communications and different
configurations that may be helpful when designing the layout and configuration
of a system. For additional help, contact Campbell Scientific.
For all communications types, if the total number of CSAT3Bs
and other sensors powered by the data logger exceeds the limit of
output current from the data logger, the power wires must be
connected to a separate 12 to 32 VDC power supply. For long
cables, a higher voltage power supply is recommended as there
will be voltage loss over long distances.
For CSAT3B sensor networks with relatively long cables, the
inductive impedance can be great enough to lead to short dips in
voltage. If the voltage drops below 9.5 VDC at the input of any
CSAT3B sensor, that sensor will report a Low Voltage diagnostic
bit (see TABLE
) and the
Status
light will flash red. To resolve
this issue, power the CSAT3B network using a higher voltage (up
to 32 VDC) or install a capacitor at one of the current loads. If
needed, contact Campbell Scientific for assistance.
Not all of the data loggers that are compatible with the
CSAT3B support the same voltage input range as the
CSAT3B. While the CSAT3B supports voltage of up to
32 VDC, many data loggers require lower voltage. For
example, the CR800 and CR3000 require 9.6 to 16 VDC
when connecting to the front panel voltage input, the
CR1000X requires 10 to 18 VDC.
If a CR3000 has a rechargeable base, then a 17 to
28 VDC power supply may be connected to the base.
Unlike most of the data loggers, the CR6 does support
up to 32 VDC if the power supply is connected to the
CHG input terminals. For more details, refer to a data
logger user manual.
7.7.1 SDM Communications
If data collection from the anemometer is to be accomplished using a data
logger with SDM communications, connect a CSAT3BCBL1 to the
Power/SDM
port by screwing in the M16 connector into the port until tight as
shown in FIGURE
. No other cables are required for SDM communications,
as the CSAT3BCBL1 contains both power and SDM wiring.
If only one CSAT3B is being measured, the opposite end of the cable will have
wire pigtails if connecting directly to the ports on a data logger. Refer to
(p. 4)
, for this wiring. Connect the
white, yellow, and blue wires to the
SDM-C1
,
SDM-C2
, and
SDM-C3
ports
respectively, on a data logger (FIGURE
). On a data logger or another 9.5 to
32 VDC power supply, connect the red and black wires to the
12 V
and
G
NOTE
NOTE
WARNING
