LI-COR LI7200RS, Инструкция по эксплуатации

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absorbed by the detector (see Cross Sensitivity on page 8-3 and Zero Drift on
page 8-3).
The calibration coefficients, XS, and Z values are unique to each sensor head, and
may be found on the calibration sheet shipped from the factory. The Band Broad-
ening coefficient is 1.15 for all sensor heads.
The calibration coefficients are stored in the LI-7550 Analyzer Interface Unit, not
the sensor head. To change these values, edit them and then click Apply to send
these values to the LI-7200 for implementation.
Caution: To avoid undesirable changes to the instrument performance, do not
edit values in this window. Click
Cancel
to avoid any undesirable changes.
The Head Serial Number displays the serial number of the sensor head that is asso-
ciated with the coefficients.
When exchanging sensor heads, it is necessary to change calibration coefficients,
and to redo the zero and span.
Note: The easiest way to get the calibration coefficients, zero, and span updated
for a sensor head is to save the configuration (it is a *.7x file) and then upload
the file to a different LI-7550 using
Open Configuration
.
Manual Tab
The
Manual
tab displays current values
for CO
2
and H
2
O zero and span; after
performing a zero and span calibration,
these values should be near 1 (zero is typ-
ically between 0.8 and 1.2, and span is
typically between 0.8 and 1.2;
Z
wo
and
Z
co
, see equations 8-14 and 8-17). Span 2
values will be near zero.
We recommend that you track the zero
values over time as you re-zero the instru-
ment. As the internal chemicals lose
their effectiveness, this value will
increase. The CO
2
zero drift is also somewhat temperature dependent.
Section 7. Software Reference
7-23 Manual Tab