Campbell CSAT3, Instruction Manual

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CSAT3 Three Dimensional Sonic Anemometer
11
TABLE 5-8. FW05/FWC-L35 Fine
Wire Thermocouple
Description Color
Signal High Purple
Signal Low Red
6. CSAT3 Outputs
The CSAT3 has three signal outputs: SDM, RS-232, and analog. Campbell
Scientific recommends that the SDM output be used when ever possible, followed
by RS-232, and finally analog. TABLE 6-1 summarizes the difference between
the three output options. In general SDM communications has the following
advantages: lowest CSAT3 current drain, best control and diagnostics, and
highest data resolution.
TABLE 6-1. CSAT3 Outputs
SDM RS-232 Analog
Typical
Current Drain
@ 10 Hz
51 mA
@ 12 Vdc
89 mA
@ 12 Vdc
99 mA
@ 12 Vdc
External
Trigger
Source
yes yes no
Output
Dynamic
Range
19 bit 19 bit 12 bit
Diagnostics
Available
yes yes no
6.1 SDM Output
SDM is a Campbell Scientific communication protocol used between a
Campbell Scientific datalogger and a smart sensor. TABLE 6-2 lists all the
Campbell Scientific dataloggers that support SDM communications, along with
the required datalogger OS/PROM and CSAT3 embedded code.