Sequoia LISST-ABS, Руководство пользователя

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Appendix B: Converting Uncalibrated Concentration to Concentration
Formula
Recalibration
The relationship between Uncalibrated Concentration (C
u
) and
suspended concentration (C) is
C = Cu * Cal Factor
Where CalConst is characteristic of a sediment size and type. All
LISST-ABS instruments are calibrated using glass spheres between 63
and 90 microns. They are configured so that Cal Const = 1 for these
particles. This makes all LISST-ABS sensor interchangeable.
Note that Cal Factor is the only variable that changes upon
recalibration.
Recalibration of the sensor for different size or types of particles
involves finding a new value for Cal Factor. Recalibration can be done
by using the provided Windows software. You will need to prepare a
known concentration of your suspension, in a very well-mixed chamber.
Insert the instrument, apply power. The instrument displays
Uncalibrated Concentration at the previously held value of Cal Factor.
At any time, Press the Recalibrate button and follow instructions. At
the end of about a minute, the software computes the new Cal Factor
and loads it into the designated box. The measurements that follow use
this value of Cal Factor to convert Uncalibrated Concentration to
Concentration in mg/L.
This value is not saved on the instrument . It is
only used in the Windows software. Record this value in your notes for
future reference. For detailed instructions on using the LISST-ABS
software see Section 2.5.