Service manual

9-2013 4. Service
4.6.5 Alternator Temperature Switch
The alternator temperature switch contacts are normally closed. The switch contacts open at
170 °F ± 5°.
4.7 Generator
4.7.1 Operation
This is a single-bearing, two-pole, revolving field generator with brushes and slip rings. Output
voltage is regulated by the generator set control.
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 generator field.
See Testing the Generator.
Rotor: The rotor consists of a shaft with steel laminations wrapped with field windings. A
molded slip ring assembly is pressed on to supply 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 centered on and 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).
A030A239 (Issue 10) 33