Thermo King SGCO 3000, Manual

Page: 115 / 144

115
Alternator Operation and Diagnosis
General Description
The 460/230 Vac alternator system consists of two
principal components: the main alternator, and the
SG+ Controller.
The main alternator may be subdivided into the
4-pole main rotating field and the main stator
winding.
The main rotating field, the rotating rectifier and
the exciter armature are all mounted on a common
shaft. Output of the exciter is rectified by the shaft
mounted rotating bridge rectifier. This provides
excitation to the main alternator rotating field.
The SG+ Controller energizes (and controls) the
exciter field. The output from the main winding
builds up until the voltage and amperage reaches
the rated amount. The controller then decreases
field current, and the alternator maintains the
proper output voltage.
Dual Voltage Alternator
The generator set is factory wired for 460V power
output. The alternator output can be changed to
230V by changing the jumper wire connections at
the terminal strips in the control box. See
“Rewiring Procedures for Changing the Generator
Set Output Voltage” on page 123.
Figure 92: 460/230 Vac Alternator Component Function