Stanford Research Systems RGA100, Operating Manual And Programming Reference

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Filament Replacement 8-11
SRS Residual Gas Analyzer
Filament Replacement
The filament eventually wears out and needs to be replaced. There is no need to send the
RGA unit back to the factory for this service. The replacement procedure is simple and
can be completed in a few minutes by qualified personnel.
The filament is very delicate and should be handled with extreme care. The thoria
coating is very delicate and can easily be damaged if the filament is mishandled. Please
read the following handling recommendations before opening the filament’’s box:
Handling and care of the filament
x
Do not bend, or twist the filament .
x
Do not scratch the filament’’s Thoria coating.
x
Do not handle the filament directly with your fingers, use fine tweezers, and hold it
by the platinum tabs only.
x
Do not attempt to clean the filament.
x
Use only SRS provided filaments as replacement.
Equipment
x
Filament Replacement kit: consisting of new filament, and spare screws and nuts.
x
One standard OFHC copper gasket for 2 3/4”” CF Flange. New and Clean!
x
Precision flat-head screw driver: 2.5 mm head.
x
Needle nose pliers.
x
Latex gloves/powder free.
x
Clean, dust-free work area.
Procedure
1. Read all warnings at the beginning of this chapter before attempting to service the
probe.
2. Set up in advance a clean, dust-free working area where to carry out this procedure.
3. Turn off the RGA and disconnect the ECU from the probe.
4. Wait for the probe to cool down for at least 30 minutes after the emission is turned
off. Severe burns can result if the probe is handled too soon .
5. Unscrew the six bolts from the RGA’’s mounting flange and remove the entire probe
from the vacuum system (Note the rotational orientation of the RGA Mounting
Flange before removing the probe from the vacuum system so that it can be placed in
the exact same orientation at the end of the procedure. Mark the side of the flanges
with a permanent marker if necessary.). The ionizer is now fully exposed and easily
accessible.