Service Manual

Table Of Contents
6. Service10-2019
109A062J683 (Issue 1) Copyright © 2019 Cummins Inc.
6.5 Alternator
Alternator Components
This is a single-bearing, two-pole, revolving field alternator with brushes and slip
rings. Output voltage is regulated by the generator set control. Here are the major
components:
Component Description
Stator The stator consists of steel laminations with two sets of windings in the
lamination slots. The main windings (L1-L2, Neutral) power the connected
loads and the quadrature windings (Q1-Q2) supply power for the alternator
field. See the Testing the Alternator section.
Rotor The rotor consists of a shaft with steel laminations wrapped with windings. A
molded slip ring assembly supplies field current to the rotor windings
through the brush block assembly. The rotor shaft is supported in the end
bell by a sealed ball bearing. The rotor is driven by the taper on the end of
the engine crankshaft.
Brush Block Field current passes through the brush block which has two spring-loaded
carbon brushes that make contact with the rotor slip rings.
Voltage
Regulator
The generator set control maintains constant output voltage under varying
load conditions by varying field current. Power for field excitation is supplied
by the quadrature winding (Q1-Q2).