Thermo Scientific DSQ II, Руководство по оборудованию

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3
Troubleshooting
Sensitivity Symptoms
146 DSQ II Hardware Manual Thermo Scientific
No ions are visible in Tune after selecting “Restore Default Calibration”.
Possible Solutions
• Instrument is not calibrated. Run an automatic tune with all calibrations selected.
• No high m/z ion intensity because the RF is not tuned correctly. See “RF and DC Control
Symptoms” on page 141 .
Poor high mass response.
Possible Solutions
• No high m/z ion intensity because the RF is not tuned correctly. See RF and DC Control
Symptoms p. 141 .
• The ion volume, lenses, or prefilter are dirty. Clean the ion volume, lenses, and prefilter,
as described in “Cleaning the Ion Source, Lenses and Prefilter” on page 45 .
• Poor high m/z ion ratios because the ion source temperature is too high. Reduce the ion
source temperature to reduce the amount of thermal decomposition and fragmentation of
your analyte.
• The conversion dynode is disconnected or faulty. Check the cable or replace the electron
multiplier/conversion dynode power supply.
• Reagent gas is leaking into the analyzer and suppressing the EI signal. Check for the
presence of CI reagent ions in the spectrum. If necessary, replace the CI reagent gas flow
module, as described in
“Replacing the CI Reagent Gas Flow Module” on page 79 .
Poor low mass sensitivity or
m/z
219 is base peak for calibration gas.
Possible Solutions
• Prefilter offset voltage is too negative. Adjust the prefilter offset closer to zero.
• The ion volume, lenses, or prefilter are dirty. Clean the ion volume, lenses, and prefilter,
as described in “Cleaning the Ion Source, Lenses and Prefilter” on page 45 .
• Prefilter is misaligned or broken. Check the alignment of the prefilter.
• Lens voltages are incorrect. Select Restore Default Tune in DSQ II Tune .