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34
Troubleshooting and Maintenance Manual
2
General Troubleshooting
Mass Spectra General Symptoms
This section describes symptoms you might observe in mass spectra. Some of
these symptoms will appear in the mass spectra of samples. Others you will
observe only in a tune report. Some of these symptoms have causes that can be
corrected by the operator. Others, however, require service by an Agilent
Technologies service representative.
Two of the chromatographic symptoms,
Poor sensitivity
and
Poor
repeatability
also apply to mass spectra.
No peaks
•
Ion source cables not connected
•
Bad connections to or from the detector
•
HED power supply output cable has failed
•
Collision cell voltages
•
Collision cell gas flow
•
Other electronics failure
•
Incorrect tune file (inappropriate parameters)
Isotopes are missing or isotope ratios are incorrect
•
Wrong precursor or wrong product ion was selected
•
Scan speed is too high (MRM mode)
•
Dwell time is too short (MRM mode)
•
Electron multiplier voltage is too low
•
Repeller voltage is too high
•
Wrong ions are chosen
•
High background
•
Dirty ion source
•
Collision cell voltage
•
Collision cell gas flow
•
Detector iris not working
Содержание 7000 Triple Quadrupole GC/MS
Страница 24: ...24 Troubleshooting and Maintenance Manual 1 Introduction...
Страница 50: ...50 Troubleshooting and Maintenance Manual 2 General Troubleshooting...
Страница 122: ...122 Troubleshooting and Maintenance Manual 4 General Maintenance...
Страница 144: ...144 Troubleshooting and Maintenance Manual 6 Vacuum System...
Страница 182: ...182 Troubleshooting and Maintenance Manual 8 Electronics...
Страница 193: ...Replacement Parts 9 Troubleshooting and Maintenance Manual 193 Figure 45 Foreline pump top and safety cage parts 1 6 5 7...
Страница 212: ...212 Troubleshooting and Maintenance Manual 9 Replacement Parts Figure 50 CI flow control module 5 3 4 2 1...
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Страница 214: ...Agilent Technologies Agilent Technologies Inc Printed in USA September 2009...