Removal Of The Rectifier Diodes - Sincro SK315 Serie Manual De Uso Y Mantenimiento

It's important that the rotor is additionally supported
by crane since, once the rotor is out of the stator
core, it may slip and cause damage to persons or
materials.
IMPORTANT!
Reassembly
Reassembly of the rotor should be made in reverse
order of the operation described above taking in the
account the following cautions:
• in case that the any part of the rotor is changed, the
complete rotor must be re-balanced;
• in case of single bearing alternators, check if the
coupling discs are damaged.

7.2.4 Removal of the rectifier diodes

• Remove generator end-shield cover;
• in case that the generator is equipped with PMG, make
the procedure as described in 7.2.1. – Removal and
re-assembly of the PMG;
• unscrew the 8 (6 on SK315/355 series) screws that
fasten the end-shield to the housing;
• apply simultaneously two screws M12 on the two
threads M12 (placed on the opposite sides of the
end-shield) and slowly start to remove the end-shield
from the bearing. This process should be applied until
the end-shield comes out max. 20mm. In this position
there is enough space to change the rotating bridge.
Pay special attention not to drive the end-shield too
much to avoid to slips from bearing since in that
moment becomes free and could be damaged or even
cause the injuries to persons. As a precaution, using
the lifting bolt on the top of the end-shield, secure the
end-shield before starting of this process;
• unscrew the 3 nuts that hold the diode leads together
with rotor exciter leads;
• unscrew additional two nuts that keep the diode
aluminum plates together with the main field leads
and protective varistor;
• take out the two aluminum plates that each carries
three diodes.
Reassembly
Reassembly of the rectifier diodes should be made in
reverse order.
NOTE: The procedure of the replacing the rectifier diodes
can be also made in a way that the complete end-shield
is removed. In this case follow the procedure as it's
described in the NDE bearing replacement and after the
end-shield has been removed, follow the procedure of
changing the diodes plates out as it is described above.
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