Metrohm NIRS XDS Transmission OptiProbe Analyzer - Manual (Page 59)

▪▪▪▪▪▪▪ 57
Performance Test measures peak positions of internal reference materials, and these positions are
used as a method to maintain wavelength measurement at the sample plane, using the external
standard. As discussed under Performance Test, the internal reference materials are not traceable,
and are only used as an internal method of maintaining correct wavelength measurement on the
external wavelength standard.
Note that Bandwidth is only computed on the XC-1300
WST3Wxxx “Trans Cal Std”, which is the same standard
used in Instrument Calibration. (Shown on left.) The printout
above is for WST3W011, and will be similar for other
serialized XC-1300 wavelength standards.
Bandwidth is not calibrated or measured when using “Poly-
Didym”. (Shown on right.) That standard also does not
provide the tighter FOSS-defined peak readouts, as set in
Instrument Calibration. It is included in XC-1310 and XC-
1320 as an independent check from the XC-1300 standard,
for those who desire a separate wavelength standard from
that used in Instrument Calibration.
When Wavelength Certification has passed, the user should click the cursor on the tabular display, go
to the File menu, and click Print to keep a copy of the report. It is saved in the Diagnostic Database
for future recall. See the Vision manual for a full explanation.
If the instrument passes the NIST-type peaks (page 1 of the
report), but fails on the FOSS-defined peaks, Vision will
recommend that the user run Instrument Calibration to set
the wavelengths properly.
Instrument Calibration must be checked under Project
Options to get this message.
Verify that the instrument is fully warmed up, and run the test
again. If this message is shown, re-run Instrument Calibration.
This will set the wavelengths to the required values.
A note about Performance Test:
Performance Test measures peak positions of internally-mounted wavelength reference materials.
These positions are used as a method to maintain wavelength measurement at the sample plane,
using the external standard. As discussed under Performance Test, the internal reference materials
are not traceable, and are only used as an internal method of maintaining correct wavelength
measurement on the external wavelength standard, used in Wavelength Certification.
7.2.3 Photometric Test
Photometric Test provides a method to verify ongoing photometric performance of the instrument.
This is a requirement for pharmaceutical users. Test results are stored in the Diagnostic Database, and
may be accessed at any time. Control charts are plotted (after several tests have been stored) to
provide an ongoing record of performance.
The test uses the same standards used in IPV Setup. Photometric Test compares current spectra of