Aftersales Assistance And Maintenance; Control Of Windings And Electrical Insulation; Control Of Bearings - Sincro FB2 MB Manual Del Usuario

7. AFTERSALES ASSISTANCE AND
MAINTENANCE
The maintenance and fault diagnostic
!
procedures involve risks that may cause
severe injury
WARNIG!
procedures should therefore be carried
out solely by qualified electrical and mechanical
specialists. Before any maintenance and cleaning
work make sure that there are no live parts, that
the generator housing has cooled to ambient
temperature, that the electricity generating set can
not be accidentally started up and that all procedures
are strictly observed.

7.1 Control of windings and electrical insulation

The condition of the windings can be checked by measuring
their electrical resistance to earth. While running this test
disconnect the voltage regulator. It is usually sufficient to
control the main winding.
The readings should give a measurement of at least
2MOhm. If the insulation resistance is below this threshold,
the alternator alone should be oven dried at 60 ÷ 80°C
for 3 hours. Before carrying out this operation remove the
voltage regulator. As an alternative to oven, drying hot air at
60 ÷ 80°C can be blown through the alternator for at least
1 hour.

7.2 Control of bearings

The bearings are sealed and maintenance free.
During maintenance control the condition of the bearings
and check that no grease has leaked; the lifespan of the
bearings depends on the vibrations and axial strains they
undergo (vibrations can increase considerably with a bad
alignment) and on the working conditions. So check for any
unusual signs: vibrations, unusual noises.
If undue vibrations or noises appear after long-term usage,
these could be due to a worn bearing that, if damaged, has
to be replaced.
The bearing should always be replaced after 20.000
working hours.
or even death. These
A bearings lifespan is closely linked to the
i
working conditions and environment.
IMPORTANT!
Long periods of sustained vibrations can
i
damage the bearing balls and their seat.
Too high humidity can emulsify the grease
IMPORTANT!
and encourage corrosion.
Intense vibrations caused by the engine
i
or bad alignment of the components
in the electricity generating set put the
IMPORTANT!
bearing under stresses that will reduce its
lifespan.
ENGLISH
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