2000 MS Hardware Maintenance
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Troubleshooting
There are two procedures for isolating problems associated with the Mass
Spectrometer. Running the Auto Tune routine from System Control will provide
you with information about system performance. Running the diagnostics
program will initiate a hardware test. These tests may be used to isolate simple
ion trap problems, e.g., air leaks, burned-out filaments, high contamination levels,
etc.
NOTE: If diagnostics fail, once the problem is corrected, the
Reset
button must
be clicked before further testing.
In certain cases, you may need to physically separate the GC and MS to isolate
an ion-trap problem. In these cases, remove the column from the injector, and
plug its end with a septum. This will minimize the input of air. Maintain the
column and transfer line at ambient temperature to prevent degradation of the
stationary phase. You do not need to vent the MS vacuum system to complete
this procedure.
If you wish to further isolate the mass spectrometer, you must remove the
column from the ion trap by shutting down the system and capping the transfer
line with a no-hole ferrule.
How to Troubleshoot Problems with Spectra
The following describes the common problems a user may encounter with an Ion
Trap Mass Spectrometer.
What To Do If No Spectrum Appears
If a spectrum fails to appear on the screen when you click on the ion trap icon in
the Instrument Control Page, regardless of mass range, you should investigate
the following potential causes:
•
The method segment is a FIL/MUL Delay and ionization is EI (AUTO or
FIXED) mode. During FIL/MUL Delay the trap icon is red.
•
The filament is open.
•
The turbomolecular or diffusion pump has stopped.
•
An RF adjustment is required.
•
The instrument parameters are inappropriate.
•
The trap has been incorrectly assembled.
•
There is a problem with the electronics.
•
The system has not finished baking out.
Before you begin troubleshooting, however, be sure that you have baked out
Saturn for at least 2 hours. Run Diagnostics to determine if any hardware
problems are present. If you have done this, and the missing-spectrum problem
persists, continue as follows. These steps apply if either air/water or cal gas
peaks are missing.
