Foss NIRS DS3, Руководство пользователя

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Fig. 108
Instrument calibration should be carried out when prompted by the software or
when recommended by a FOSS representative. Not performing the instrument
calibration when prompted will not prevent you from analysing samples (or other
tasks) but all samples will be marked with the warning 'Instrument needs
calibration'.
Instrument Calibration is also recommended after lamp replacement in NIRS DS3 /
DS3 F.
Below is a description of the two operations but remember that both parts,
Wavelength Calibration and Intensity Correction, are always carried out in
sequence during Instrument Calibration. They cannot be initiated separately.
ISIscan Nova will collect and include the results from both sequences in its
advanced mathematical treatment in order to secure the optimal instrument
calibration in terms of wavelength, bandpass and intensity accuracy.
NIRS DS3 / DS3 F uses an innovative method of wavelength calibration to assure
consistency between instruments. A wavelength standard using materials with
known stable peak positions is used to calibrate the wavelength scale of each
instrument.
The internal and the external wavelength reference standard are made of identical
material. At FOSS, these wavelength standards are calibrated on a controlled
master instrument.
Each standard has its own unique factors that are used to ensure an accurate and
traceable link to the master instrument. The calibration nominals for the external
standard are delivered on a USB key together with the EWC cup. The calibration
nominals for the internal wavelength standard are stored inside the instrument
internal software.
For routine operation the internal wavelength standard is recommended when
performing instrument calibration.
The use of the external wavelength standard is only recommended when vital parts
inside the instrument have been replaced, so it should only be used by trained
service engineers.