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Abrasion:
Abrasion or contamination from other sources, such as
chemicals and abrasive or conducting substances, may damage coil
and connection surfaces.
Cracking:
Cracking or abrasion of insulation may result from
prolonged or abnormal mechanical stress. In stator windings,
looseness of the bracing structure is a certain sign of such phenomena
and can itself cause further mechanical or electrical damage if allowed
to go unchecked.
Erosion:
Foreign substances impinging against coil insulation surfaces
may cause erosion.
Cleaning
Exterior:
Wipe loose dirt from the exterior with a clean, lint-free cloth.
Remove stubborn accumulations of dirt with a detergent or solvent
that won’t damage the paint or metal surfaces. Use a vacuum to clean
ventilating ports.
Windings, Assembled Machines:
Where cleaning is required at
the installation site and complete disassembly of the machine is
unnecessary or not feasible, pick up dry dirt, dust or carbon with a
vacuum cleaner to prevent the redistribution of the contaminant.
A small non-conducting nozzle or tube connected to the vacuum
cleaner may be required to reach dusty surfaces or to enter into narrow
openings. After most of the dust has been removed, a small brush can
be affixed to the vacuum nozzle to loosen and allow removal of dirt
that is more firmly attached.
After the initial cleaning with a vacuum, compressed air may be
used to remove the remaining dust and dirt. Compressed air used
for cleaning must be clean and free of moisture or oil. Air pressure or
velocity must be adequately controlled to prevent mechanical damage
to the insulation.
Disassembly of the machine and more effective cleaning by a qualified
Kato technician may be required if the above described field service
cleaning procedures do not yield effective results.
Windings, Disassembled Machines:
Take an initial insulation
resistance reading on the machine to check electrical integrity. The
high pressure hot water wash method of cleaning, which sprays a
high velocity jet of hot water and water containing a mild detergent, is
normally effective in cleaning windings, including those subjected to
flooding or salt contamination. Use multiple sprays with clean water to
remove or dilute the detergent following the detergent spray.
Dry the machine until acceptable insulation resistance values are
obtained at room temperature. See the insulation resistance procedures
below for minimum recommended values.
Electrical Contacts:
Clean electrical contacts, switch contacts and
terminals with an approved contact cleaner. Do not file contacts.
WARNING:
When using cleaning
solvents, ensure adequate ventilation and
user protection.
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