LI-COR LI-600, Инструкция по эксплуатации

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LI-600 Porometer/Fluorometer Instruction Manual
9-6
where V is the voltage read from the sensor, Z is a user-
settable zero parameter and S is a user-settable span para-
meter and f(x) is a 3rd or 4th order polynomial.
RH sensors
The RH Sensors have a small sensitivity to temperature
that must be accounted for. A temperature correction
occurs both in the zero setting and in the calibration
function. The sample RH sensor also must be corrected
for a match offset, as shown in
Additional calculations for
porometry on page 9-8. We will use the terminology of
RH
r
and RH
s
to indicate sensors before the cuvette (ref-
erence) and sensors after the cuvette (sample). Note that
a match offset is applied to the
RH
s
value (equation
9-16).
9-12a
9-12b
where m
x
and b
xz
are factory-determined coefficients and
T
ref
is a thermistor embedded in the block adjacent to
the RH sensors.
Converting RH sensor voltage to RH (%) requires 4 fact-
ory-determined coefficients and the zero and span set-
ting for each sensor.
9-13a
9-13b
where subscript r and s represent the reference and
sample RH sensors, respectively. is the sensor
voltage, is the user-settable sensor zero, is the
user-settable span (nominally 1.0).