Sequoia LISST-200X, Руководство пользователя

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LISST-
200X User’s Manual
13 LISST-200X Introduction & Quick Start
Step 9:
Acquiring Clean
Water
Background
Measurement The background scattering measurement is critical to good instrument
performance. It is especially critical for clean water applications where
the optical transmission is greater than 90% over the 2.5cm path. The
background scattering will also check the overall health of the
instrument. It will verify that all of the systems are functioning and that
the optics is still in alignment. The current background will be acquired
and displayed relative to the factory background scattering and the
most recently saved background that is stored on the instrument. The
image below shows an example of this display. It is opened by
selecting the
Collect/View Background button.
The factory background file will be automatically acquired from the
instrument and displayed as a red line on the screen.
The ‘Current
Background’ is the last background that was collected and saved on
the instrument (the date of collection is displayed in the legend). Tips
for collecting a background are also displayed on the screen. Pressing
the ‘Background Help’ button will open a PDF with additional
information about background measurements. When the
Collect New
Background button is pressed, 20 samples will be collecting. The
average of these measurements will be displayed as a black line on
the screen.
The graph shows the value of the 36 light scattering detectors. The
red line is the factory values, the black line is the average of all 20
measurements. If the background is close to factory levels the
message displayed will indicate a pass or acceptable background.
If the water or windows are not clean or if there is a problem with the
instrument, error messages and suggested actions will be displayed.