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GA10218_0101 - 9/2002
7 Calibration
7.1 Introduction
The PhoeniXL can be calibrated in two different ways:
Internal calibration by means of a built-in test leak.
External calibration by means of an additional test leak which then is
attached to the inlet port or the component under test.
During the calibration procedure the mass spectrometer is tuned to the
maximum helium or hydrogen signal and this signal is referred to the
known leak rate of the internal or external test leak. Although the
PhoeniXL is a very stable instrument a calibration is recommended every
day with heavy use, or before using the PhoeniXL from time to time, to
make sure that ambient temperature changes or dirt or other impacts
don’t adulterate the measurements.
To get an optimized calibration the machine has to warm up at least 20
minutes before use, otherwise a warning will come up which might be
ignored.
7.2 The calibration routines
The calibration routines can be started by pressing button CAL (Softkey 5)
via 3 different locations:
main menu (Fig. 16)
Stand-by mode (Fig. 8)
measurement mode (Fig. 14 & 15)
The access via Stand-by mode or measurement mode can possibly be
blocked (see Chapter 6.8.1). In this case the softkey is not labeled.
Default: Access on.
Once the calibration mode is activated the user must choose between an
internal and an external calibration. Please press the corresponding Soft
Key
Fig. 23
.
A calibration may be terminated at any time by pressing the
STOP Button
or using the Soft Key no. 1 (Cancel)
Fig. 29
.
7.2.1 Internal Calibration
Mass 4 must be selected (Default setting)
Press Softkey nr. 4
Fig. 29
to start the calibration. Once this procedure is
started the entire procedure is performed automatically. At the end (after
about 25 s) a visual and audio signal is released. Thereafter the unit is
ready for further use.
7.2.2 External Calibration
For an external calibration a test leak has to be attached to the part under
test or the inlet port directly depending on the application.
