4.
Installing the Exciter Armature
a. Preparation for Exciter Armature Installation
(1)
Clean generator shaft and exciter armature bore. Remove all rust, corrosion, etc.
(2)
Make
CERTAIN
that the leads are tucked into the 1/2" keyway, which is opposite from the 3/8"
keyway in the generator armature shaft.
(3)
Route the revolving field leads (step 2 above) through exciter armature hole (“B”, Fig. 2), which is
opposite the keyway.
(4)
Align armature keyway with key in shaft and start armature on shaft.
b. Exciter Armature Installation
(1)
If the exciter armature-to-generator shaft fit is such that the exciter armature may be pushed on
by hand, push it on very slowly while another mechanic carefully watches and pulls field leads
through hole in the exciter armature diode mounting plate. Continue installation until the diode
mounting plate contacts the end of the generator shaft. If the exciter armature cannot be pushed
on by hand, use a 1/2 - 13 X 5-inch hex-head bolt and 1/2 - 13 nut as shown in Figure 6 to pull
the exciter armature onto the generator shaft. Put the exciter armature on slowly and at the same
time pull field leads through hole (“B”, Fig. 2) in the diode mounting plate. Screw the nut onto the
bolt until it is near the head of the bolt. Insert the bolt through the hole in the center of the diode
mounting plate as far as it will go, and screw it into the 1/2 - 13 threaded hole in the end of the
armature shaft. Screw the 1/2 - 13 nut up against the diode mounting plate. Continue turning the
nut until the diode mounting plate contacts the end of the generator shaft, just as is shown in the
lower portion of Figure 6. After installation, remove the 1/2 - 13 bolt and nut.
Removing Exciter Armature from Generator Armature Shaft
Figure 5
OM-2084 / Operation and Maintenance Manual
90CU24 / Series 500392 Generator Sets
Chapter 3-1
November 27/1997
Page 6
