Varian 948, Operation And Service Manual

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Models 947, 948 and 960 Leak Detectors Operations and Service Manual
B-7
2. Remove the four Phillips head screws that hold the flange cap
➀
onto the body of the
spectrometer tube
➁
(Figure B-5).
3. Firmly but gently separate the flange cap from the ion source
➂
.
4. Remove the ion source.
Examine it and the cavity for deposits and discoloration. If either is discolored or dirty,
contact Varian Vacuum Technologies Customer Service at 1-800-8VARIAN.
NOTE
Dark carbon deposits around the ion source filament and/or a
rainbow-like discoloration on the inside walls of the ion source
cavity indicate that the spectrometer tube has been operated at
too high a pressure. This can occur from a system pressure leak
or transferring into test at too high a pressure.
5. Discard the ion source in accordance with local regulations, or return it to Varian
Vacuum Technologies for exchange.
6. Remove the ground slit plate by placing a thin, slotted screwdriver into the slot and
carefully twisting and prying with the screwdriver.
7. Place the ground slit plate on a clean surface.
8. Using the Scotch-Brite™ pad from the spectrometer tube cleaning kit, polish away any
discolored areas:
❑ Inside the spectrometer tube cavity.
❑ Discolored areas of the ground slit plate.
CAUTION
The ground slit plate is very thin. Take care not to bend or
disfigure it during cleaning.
9. Using the VacuSolv presaturated cleaning wipes and swabs, thoroughly wipe down all
surfaces of the spectrometer tube body and the ground slit plate, then let air dry.
10. Place the ground slit plate onto the locking screwdriver as you did to remove it, with the
prongs facing up.
CAUTION
The ground slit plate must be firmly seated and in proper
orientation. Failure to do so can result in unreliable test results.