Model 979 Series Helium Mass Spectrometer Leak Detector
4-18
DRAFT 9/15/03
3. Using the Scotch-Brite pad, polish away any discolored areas of the magnetic pole
pieces (Figure 4-21).
Figure 4-21
Discolored Ground Magnet Pole Piece
4. Using the VacuSolv presaturated cleaning wipes and swabs (Figure 4-22), thoroughly
wipe down all surfaces of the spectrometer tube body, magnetic pole pieces, and
ground slit plate.
Figure 4-22
VacuSolv Cleaning Wipe
CAUTION
The sensing wire on the bottom side of the Button TC is
approximately 3 mils thick. Care must be taken not to damage
this wire.
5. Examine the Button TC, taking care not to damage the wires. If there is no damage, it
may be reused after it is properly cleaned.
NOTE
If you were seeing false system pressure readings prior to
overhaul, it may be best to replace the Button TC whether or
not you detect any physical signs of damage.
6. To clean the Button TC properly, soak it in liquid VacuSolv (or acetone) followed by an
isopropyl alcohol rinse. Air dry the Button TC thoroughly before re-assembling into
spectrometer tube.
Summary of Contents for 979 Series
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