SPECS PHOIBOS 100, Руководство пользователя

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Chapter
7
Calibration
Adjustment and calibration of the power supplies has been performed at the factory.
Normally no additional work is necessary after installation. The procedures described in
this chapter are only necessary for service and fine adjustment.
The typical accuracy of the energy scale depends on the voltage range used (Table , on
page ). For the 40V range the accuracy is about 3 meV and for the 3500V range about
100 mV without re-calibration. The drifts are due to different temperatures during cal-
ibration at the factory and work in the lab. Also, the workfunction of the analyzer can
change due to bakeouts; with recalibration the accuracy of the energy scale can be sig-
nificantly improved (table on page ). If energy shifts of well known peaks occur, check
the grounding of your sample. There should be no potential difference between the
ground of the sample and the ground of the power supply.
Next, check the accuracy of the high voltage ranges (40V, 400V) with a high precision
digital voltmeter and the voltage ranges (1500V, 3500V) with an additional high
voltage probe (1000:1) section , "" on page ). To recalibrate the unit please follow the
procedures in figure 27, page 59. Please note the parameters of the modules given in
the table on page in section . A description to select a default detector voltage is giv-
en in section 9.2 on page 76 and the meaning of the threshold for the preamplifiers is
described in section 9.1.1 on page 75.
PHOIBOS 57