Hobart 120CU20, Operation And Maintenance Manual With Illustrated Parts List

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OM-2228 / Operation and Maintenance Manual
120CU20 / Series 500120 / 400 Hz. Generator Set
October15, 2013
Chapter 3-1
Page 7
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 M12-1.75 hex-head bolt and M12-1.75 nut as shown in Figure 5 to pull the
exciter armature onto the generator shaft. Put the exciter armature on slowly and at the same
time pull field leads through the hole (Figure 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 end of the armature shaft. Screw the
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 5. After
installation, remove the bolt and nut.
Figure 5 Exciter Armature Installation.
(2) Connect the two generator field leads to the exciter armature as follows:
a Connect lead with ring type terminal to the screw provided to the mounting plate (Figure 2).
b Connect the other field lead to the three leads coming off of the exciter armature windings.
Use parallel splice connector, crimp and solder for a good connection.
c Insulate with sleeving material or wrap with electrical tape.