Campbell TEMPERATURE PROBE 109SS, Product Manual

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files that Short Cut creates are a great source for programming code to start a new program or
add to an existing custom program.
NOTE:
Short Cut cannot edit programs after they are imported and edited in CRBasic Editor .
A Short Cut tutorial is available in QuickStart (p. 1). If you wish to import Short Cut code into
CRBasic Editor to create or add to a customized program, follow the procedure in Importing
Short Cut code into CRBasic Editor (p. 12). Programming basics are provided in the following
section. A complete program example can be found in Example program (p. 13).
If the 109SS probe is to be used with long cable lengths or in electrically noisy environments,
consider employing the measurement programming techniques outlined in
Electrically noisy
environments (p. 9) and Long cable lengths (p. 9).
Details of 109SS probe measurement and linearization of the thermistor output are provided in
Measurement and output linearization (p. 8).
7.2.1 Therm109() instruction
The
Therm109()
measurement instruction programs CRBasic data loggers to measure this
sensor. It applies a precise excitation voltage, makes a half-bridge resistance measurement, and
converts the result to temperature using the Steinhart-Hart equation. See
Measurement and
output linearization (p. 8) for more information.
Therm109()
instruction and parameters are as
follows:
Therm109 (Dest, Reps, SEChan, VxChan, SettlingTime, Integ/f
N1
, Mult, Offset)
Variations:
l
Temperature reported as °C — set
Mult
to 1 and
Offset
to 0
l
Temperature reported as °F — set Mult to 1.8 and Offset to 32
l
AC mains noise filtering — set
Integ/f
N1
to the 60 Hz or 50 Hz option (see Electrically
noisy environments (p. 9))
l
Compensate for long cable lengths — Set SettlingTime to 20000 (see Long cable
lengths (p. 9))
7.3 Water temperature installation
109SS probes can be submerged to 15 m (50 ft) or 21 psi. The 109SS is not weighted, so a
weighting system should be added, or the probe secured to a submerged object such as a piling.
109SS Temperature Probe 7