3Remedying Operating And Measuring Errors - Pfeiffer Vacuum PrismaPro QMG 250 Translation Of The Original

10.1.3 Remedying operating and measuring errors
Symptom / malfunction
messages
Peak detection error
(Peak detection error)
No spectra
(No spectra)
Low sensitivity
(Low sensitivity)
Possible causes
No peak for the target mass
Peak for target mass too small/
broad
Peak out of detection
Range of target mass (e.g. peak
shift > +/- 0.40 u of rated value)
Emission off
electron multiplier is switched on,
although Faraday mode is selected
Pressure or signal too low for Fara-
day detector
Electron multiplier voltage too low
No sensitivity, analyzer contaminat-
ed
Electronic unit (QME) not attached
to the analyzer correctly
Mass calibration faulty
High-frequency error
Mass filter error
EM defective
Error in the electronic unit (QME)
DSP communication error
Analyzer contaminated
Mass calibration (resolution) faulty
Analyzer operating parameters set
incorrectly
Mass filter defective or contaminat-
ed
Ion source or analyzer magnetized
Ion source or analyzer in close
proximity to magnetic fields
Incorrect total pressure measure-
ment with external gauges
System pressure too low
Error in the electronic unit (QME)
Gain of electron multiplier too low
Remedy
● Load the settings from the test report.
● Contact Pfeiffer Vacuum
● Load the settings from the test report.
● Contact Pfeiffer Vacuum
● Load the settings from the test report.
● Contact Pfeiffer Vacuum
● Load the settings from the test report.
● Contact Pfeiffer Vacuum
● Switch on the emission.
● Switch the EM off.
● Switch the EM on.
● Increase the EM voltage.
● Refer to the operating and measuring error
"Low sensitivity".
● Make sure that the electronic unit (QME) has
been completely pushed onto the analyzer .
● Ensure that the contacts are straight and are
not bent or damaged.
● Set new mass positions and resolution (tuning).
● Refer to the hardware error "HF error".
● Refer to the hardware error "Mass filter error".
● Contact Pfeiffer Vacuum
● Contact Pfeiffer Vacuum
● Contact Pfeiffer Vacuum
● Degas the ion source.
● Bake out the analyzer.
● Replace the filament unit and/or the ion source.
● Replace the analyzer.
● Contact Pfeiffer Vacuum
● Recalibrate the device (tune)
● Increase the peak width.
● Contact Pfeiffer Vacuum
● Contact Pfeiffer Vacuum
● Rectify the cause of the magnetic fields.
● Rectify the cause of the magnetic fields.
● Ensure correct calibration of the gauge being
used for sensitivity calibration.
● Increase the sample pressure, if possible.
● Contact Pfeiffer Vacuum
● Bake out the analyzer.
● Replace the analyzer.
● Contact Pfeiffer Vacuum
Malfunctions
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