LI-COR LI-7500, Инструкция по эксплуатации

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Section 3
3-22 Setup and Operation
Temperature and pressure values are required by this program for converting CO
2
and H
2
O
density to mole fraction. In addition, the LI-7500 needs a pressure value to compute CO
2
or
H
2
O mole density, and a temperature value to do the band broadening correction for H
2
O on
CO
2
.
The Inputs window allows you to specify where the temperature and pressure values are
obtained; they can be measured with the on-board sensors, via a custom sensor measured at
the Aux Input port, or hand-entered.
For temperature or pressure measured via the auxiliary input, there are two fields that allow
you to enter values for the multiplier (A) and offset (B). Linearized voltage inputs use an
equation of the form
Y = AV + B
where Y is the sensor output, V is the voltage output of the sensor, B is the Y-axis intercept
(offset), and A is the calibration multiplier, which is the slope of the line representing the
sensor's response (Figure 3-3).