Varian 990 dCLD II, Operation Manual

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5-1
Model 990 dCLD II Component Leak Detector
Section 5. Maintenance
Like other sensitive test equipment, a mass spectrometer leak detector requires periodic
maintenance to ensure continued reliable operation. After prolonged use, the leak detector
accumulates contaminants from even the cleanest of products tested. These contaminants
eventually impair operation. A thorough disassembly and cleaning of the entire vacuum
system, which includes the cal leak valve block and spectrometer tube, restores normal
operation. For heavy production use, more frequent overhauls may be needed. Conversely,
lighter use may permit a longer period between overhauls. In most cases, this work is done
by user maintenance personnel, but it may also be done by Varian under the terms of a ser-
vice contract.
This maintenance section does not cover overhaul of the entire vacuum system, nor does
it cover customer-supplied parts except for the brief discussion regarding pumps below. It
does cover maintenance that may have to be performed on a daily or as-required basis or,
if the item has not required maintenance, on an annual preventive basis.
Customer-Supplied Pumps
Most pumps require regular maintenance. Oil gets contaminated over time and has to
be replaced. In a system with dry pumps, tip seals have to be checked for wear. The cus-
tomer-supplied roughing and forepumps of the system must be maintained at the intervals
recommended by their manufacturer for this application in order to ensure reliable leak
detection by the 990 dCLD II.
Important Reminders
Heed the following notes, cautions, and warnings when performing maintenance.
WARNING
Disconnect power from the 990 dCLD II before performing any
maintenance procedure that requires physically disconnecting
any part of the system.
CAUTION
The preamplifier is a static sensitive device. Wear a grounding
device while the preamplifier is being handled.
WARNING
Store the Ion Source in a cool, dry area in a tightly sealed
container. When handling the Ion Source, wear powder-free
butyl or polycarbonate gloves. If you handle the Ion Source
with bare hands, wash them thoroughly and especially before
smoking or eating.