6 Commissioning
NOTICE
Contamination of the mass filter caused by gas discharge
If the high-frequency generator is switched on at a total pressure of >10
-4
hPa, there is risk of a gas
discharge igniting between the rods of the analyzer, which could lead to severe contamination of the
mass filter.
► When the total pressure is at >10
-4
hPa, make sure that the high-frequency generator has been
switched off.
NOTICE
Malfunctions caused by magnetic fields
Strong magnetic fields in close proximity to the ion source, channel electron multiplier or SEM, e.g.
caused by cold cathode gauges, tools, magnetic clamps, etc., can lead to malfunctions.
► Prevent influence from high-intensity magnetic fields by arranging the system components appro-
priately or by installing magnetic shields.
► Remove magnetic objects from the area of influence.
Factory setting of the parameters
Change the factory setting of the parameters only if this is necessary for your application.
Switching on the instrument for the first time
1. Before switching on, check that all parts and cables are correctly installed.
2. Switch on the control unit if the pressure is below the maximum permissible total pressure, but do
not switch on the emission yet.
– 10
-4
hPa with Faraday
– 10
-5
hPa with SEM
3. Check whether the values saved in the device match the supplied test log.
– The test log indicates the optimal values for your analyzer.
4. If the saved values do not match, use the software to configure them.
5. If you do not have the test log any more, activate the default setting for your ion source and opti-
mize it.
– In complete systems, Pfeiffer Vacuum factory-calibrated the high-frequency generator specifi-
cally for the analyzer.
Calibrating high-frequency generator
In complete systems, Pfeiffer Vacuum factory-calibrated the high-frequency generator specifically for
the analyzer. Proceed as follows if the high-frequency generator no longer is calibrated to match the
analyzer precisely.
1. Select "Det. Type: Faraday" (except if you have only the ion counter as detection equipment).
– If you only have a single EP 422, install it on the EP(FARAD) plug and connect it to connec-
tion EP(FARAD) of the QMH.
2. Switch on the emission and measure several spectra.
3. If you only have an EP 422 and no CP 400, install it on plug EP(SEM) and connect it to EP(SEM)
of the QMH.
4. If the pressure is below the maximum permissible total pressure for SEM operation (10
-5
hPa),
switch on the SEM.
5. Measure several spectra with "Det. Type: SEM" with EP 422 or CP 400.
6. Check the "Tune" setting of the HF generator.
7. If you did not get your analyzer together with the HF generator, optimize the"Resolution" setting.
8. If no regular peak width is achieved for small and large masses, adjust the peak width on the
QMH.
9. Additionally calibrate the mass scale if necessary.
Commissioning
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