Metrohm Vision – Diagnostics - Manual (Page 46)

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IPV Setup
IPV Setup is provided as a method to record initial instrument response to calibrated photometric
reflectance standards. This is normally performed upon initial installation, immediately after
Instrument Performance Certification (IPC), when a lamp has been changed, or when standards have
been re-certified.
When the standards are scanned during IPV Setup, a file is generated, and is stored in the Vision
directory. This file has the same format as the standards file, but a “V” is placed into the fourth
character of the file name. This indicates that it is a “verification” file. For example, if the standard set
has the serial number RSS10301, the IPV Setup file is named RSSV10301. If more than one module is
being used with the same set of standards, a separate IPV setup must be done for each. It is
recommended that after completion of the first IPV Setup, the user change the file name form
RSSVxxxx.da in the Windows Explorer to a name that will help in identifying the module i.e.
RSSVRCAxxxx.da. On completion of the IPV setup for subsequent modules, the same procedure for
file renaming can be followed.
With the IPV Setup file stored, the user can run Photometric Test to check the repeatability of
instrument performance. This is detailed in the previous section of this manual and in XDS manual,
under “Evaluation Diagnostics.” Photometric Test compares the current performance of the
instrument to the file stored during IPV Setup, and reports differences. If the instrument differences
exceed established tolerance limits, the test reports that, so corrective action may be initiated.
It is important that IPV Setup, and later Photometric Test, both be run with the same options selected
under Configure, Options. That is, if the IPV Setup file is acquired with Reference Standardization
switched on, and with Window Correction switched off, then
Photometric Test should be performed using the same settings. The System Manager should pay
particular attention to this. If options are not consistently applied, there will be a bias in the results of
Photometric Test. The bias may be enough to cause test failure, depending upon selections.
Because Metrohm spectrophotometers are sensitive instruments, they can detect differences in
temperature of the standards, and results may be affected slightly. To minimize this effect, be sure
the standards are at a stable temperature before use. If lab temperatures vary, the user may place the
standards inside the RCA cover for some time to let them equilibrate to a stable temperature.
IPV Setup is run as follows:
Select IPV Setup from the Diagnostics menu.
Vision requests a “Standard File”. This is provided on
a floppy diskette or CD, packed in the wooden box
with the standards.