Figure 11-14. Testing Rotation Rectifiers with an
Tag leads for later reconnection
Remove rotating rectifier with key (53 from
exciter rotor (38).
Install rotating rectifier assembly
onto exciter rotor (38).
Make certain the key is in place and the keyway in the
rotating rectifier is aligned with key before installing.
Connect leads to (+) and (-) terminals;
Replace cover (30) with screws (26 and 28),
washers (29), and nuts (27).
Repair. The rotating rectifier assembly repairs
involve replacement of diode and surge protector.
Remove and replace standard diodes (39,
figure 11-3), detail A) and reverse diodes
(42) on rotating rectifier heat sinks with
washers (41 and 44) and nuts (40 and 43).
Remove and replace surge protector (51)
sink with screws (45), washers (47 and 48), and
BEARING. The generator bearing is permanently
lubricated and sealed. If a defective bearing is indicated
by vibration or noise at the bearing housing on the
endball, the bearing can be replaced without removal of
the generator from the set.
(1) Removal. To gain access to the bearing (88,
figure 11-3), the endbell (85) with PMG
stator (33) and exciter assembly must be
removed as a unit. Use crane or hoist to
OVERHEAD OPERATIONS HAVE
INHERENT HAZARDS THAT CANNOT BE
MECHANICALLY SAFEGUARDED. HARD
HATS AND SAFETY SHOES ARE
Remove cover (30) by removing screws (26 and
28), washers (29), and nuts (27).
USE EXTRA CARE WHEN REMOVING
ROTOR TO PREVENT INJURY TO HANDS
DUE TO MAGNETIC ATTRACTION
BETWEEN THE PMG ROTOR AND THE
PMG STATOR OR GENERATOR SHAFT.
Remove PMG rotor (37) by removing pin (36),
screw (35), and washer (34).
Do not subject PMG rotor to severe
Loosen setscrews (52) in exciter rotor (38).
Remove exciter rotor (38).
Remove screws (82) and washers (83) to free
bearing cap (84).
Attach crane or hoist to endbell (85). Remove
bolts (80) and washers (81). Remove endbell (85)