Metrohm NIRS XDS Process Analyzer – DirectLight/NonContact - Manual (Page 71)

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When prompted, position the WSR103xx
Wavelength Standard Cell on the probe as shown.
The label should always be in a consistent position.
In this case, the bottom of the label is parallel with
the holder.
Click “OK” to continue.
This test takes about 45 seconds.
Wavelength response is adjusted for each defined peak, to assure precise wavelength registration
between instruments. At the same time, bandwidth (bandpass) is measured, and is iteratively
adjusted to an optimum value for measured peaks. This assures good agreement from instrument to
instrument, should multiple instruments be used for analysis of similar products. This calibration is
needed to insure calibration transfer, as peak shape may be slightly affected by fiber length.
At the end of the test this dialog box is displayed.
If hard copy is desired, click on “Print”.
Click “OK” to exit Instrument Calibration.
Select the next channel, if used. From the menu
bar, click on Acquire, then Select Channel. Use the
spinner to select the correct channel, then click on
“OK”.
This must be performed for each channel. Always
verify the channel before proceeding with the test.
Information about the Reflectance wavelength standard:
The reflectance wavelength standard used is directly traceable to NIST SRM-1920a, through direct
comparison on the Metrohm Master Reflectance Instrument, and in chemical formulation. In addition
to the prescribed formulation, one additional ingredient is added, in a small amount, to provide
peaks beyond those normally found in SRM-1920a. This material has very sharp bands, which are
found to be stable and repeatable.