LI-COR LI-7500, Инструкция по эксплуатации

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Section 1
Introduction 1-9
9
Verify AGC
Click on the Diagnostics tab, and view the AGC value. Make a note of this value, as it
represents the "clean window" baseline value (assuming your instrument is new). Typical
"clean window" values are 55 to 65%. As dirt accumulates on the windows (or anywhere in
the optical path), the AGC value will increase to 100%. The instrument will still function
correctly at 100%, but there is not much room for further compensation, so the windows
should be cleaned before it reaches 100%.
10
(Optional) Verify Calibration
If you have facilities to check zero and span, do so now (see Section 4, Calibration). This was
done at the factory prior to shipping, so should not be necessary on new instruments*. Note
the zero values for CO
2
and H
2
O, if this is a new instrument. As the internal chemicals
become depleted, these values will increase (when you re-zero).
* If you find the span needs re-setting, it is possible that your CO
2
(or H
2
O) standards differ
from LI-COR's.