Generator - Hobart 60PL20 Operation And Maintenance Manual

OM-2053
D. Generator
The 400-Hz generator is a brushless, revolving field, three-phase, alternating current type. The rotor
assembly is mounted by two, permanently lubricated, sealed, ball bearings. The front bearing is sup-
ported by the fan housing; the rear bearing is mounted in the exciter housing. Both of these housings
are attached to the main generator stator housing. The front end of the rotor shaft extends forward be-
yond the rear bearing and into the exciter stator housing. The exciter rotor is mounted on this shaft ex-
tension with a Woodruff key and is secured by a washer and 1/2"-13 thd, cap screw. A rectifier with
six diodes is mounted on the exciter rotor and converts exciter AC output to DC for excitation of the
generator revolving fields. The exciter DC output to the generator fields, and consequently the gener-
ator output, is controlled by the amount of DC voltage supplied to exciter fields by the static voltage
regulator. A centrifugal, radial-blade fan which is part of the hub and coupling assembly, draws cool-
ing air over all internal windings. Air enters at the exciter end and is discharged at the drive end. The
complete generator is bolted to the engine flywheel housing.
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1. Pipe, manifold-to-muffler
2. Muffler
3. Tail Pipe
Exhaust System
Figure 5
December 31/91 Revised