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3 Troubleshooting the MSD
Error messages
Turbomolecular pump
• Large vacuum leak is preventing the turbo pump from reaching 50% of full speed
• Foreline pump is not working correctly
• Turbo pump is not working correctly
• Turbo pump controller is not working correctly
• MSD electronics are not working correctly
Foreline pressure has exceeded 300 mTorr
Only diffusion pump-equipped MSDs have a foreline pressure gauge.
• Excessive carrier gas flow (typically > 5 ml/min)
• Excessive solvent volume injected
• Large vacuum leak
• Collapsed or kinked foreline hose
• Foreline pump is not working correctly
• Foreline gauge is not working correctly
Internal MS communication fault
• MSD electronics are not working correctly
Lens supply fault
• Electrical short in the analyzer
• MSD electronics are not working correctly
Log amplifier ADC error
• MSD electronics are not working correctly
No peaks found
• Emission current was set to 0
• Electron multiplier voltage is too low
• Amu gain or offset is too high
• Calibration valve is empty
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