Campbell 110PV, Инструкция по эксплуатации

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110PV Surface Temperature Probe
14
Where T
K
is the temperature in Kelvin. The Steinhart- Hart coefficients used
are:
A = 1.129241x10 –3
B = 2.341077x10 –4
C = 8.775468x10 –8
8.3 Electrical Noisy Environments
AC power lines, pumps, and motors, can be the source of electrical noise. If
the 110PV probe or datalogger is located in an electrically noisy environment,
the 110PV probe should be measured with the 60 or 50 Hz rejection option as
shown in Appendix B.1.1 ,
Half Bridge CR1000 Program
(p. B-1)
, and Appendix
B.1.2 , 4-Wire Half Bridge CR1000 Program
(p. B-3)
.
8.4 Long Lead Lengths
Cable resistance can cause significant error (FIGURE 8-2 through FIGURE
8-5 ). For each 110PV, the cable resistance (ohms) is printed on the heat shrink
label on the sensor cable. When measuring the 110PV in a 3-wire
configuration, the cable resistance can be subtracted from the measured
resistance value (see Appendix B.1.1 , Half Bridge CR1000 Program
(p. B-1)
, and
Appendix B.2 , Example CR200X Program
(p. B-4)
).
Alternatively, the 110PV-L’s cable includes leads allowing it to be measured
with a 4-wire half bridge configuration, which corrects for cable resistance (see
Appendix B.1.2 , 4-Wire Half Bridge CR1000 Program
(p. B-3)
).
Additional settling time may be required for lead lengths longer than 300 feet,
where settling time is the delay before the measurement is made. The 60 and
50 Hz integration options include a 3 ms settling time; longer settling times can
be entered into the Settling Time parameter.