Charging System Description And Operation; Generator; Regulator; Circuit Description - Chevrolet Corvette 2005 Owner's Manual

2005 Chevrolet Corvette Restoration Kit
As soon as the solenoid switch contacts close, current stops flowing thorough the pull-in winding as
battery voltage is now applied to both ends of the windings. The hold-in winding remains energized; its
magnetic field is strong enough to hold the plunger, shift lever, starter drive assembly, and solenoid
switch contacts in place to continue cranking the engine. When the engine starts, the pinion gear overrun
protects the armature from excessive speed until the switch is opened.
When the ignition switch is released from the START position, crank voltage is removed from the starter
solenoid S terminal. Current flows from the motor contacts through both windings to ground at the end of
the hold-in winding. However, the direction of the current flow through the pull-in winding is now in the
opposite direction of the current flow when the winding was first energized.
The magnetic fields of the pull-in and hold-in windings now oppose one another. This action of the
windings, along with the help of the return spring, cause the starter drive assembly to disengage and the
solenoid switch contacts to open simultaneously. As soon as the contacts open, the starter motor is
turned off.
Charging System Description and Operation
Generator
The generator features the following major components:
• The delta stator
• The rectifier bridge
• The rotor with slip rings and brushes
• A conventional pulley
• The regulator
The slip ring and the frame are liquid cooled.
The generator features permanently lubricated bearings. Service should only include tightening of mount
components. Otherwise, replace the generator as a complete unit.
Regulator
The voltage regulator controls the rotorfield current in order to limit the system voltage. When the field
current is on, the regulator switches the current on and off at a rate of 400 cycles per second in order to
perform the following functions:
• Radio noise control
• Obtain the correct average current needed for proper system voltage control
At high speeds, the on-time may be 10 percent with the off-time at 90 percent. At low speeds, the on-time
may be 90 percent and the off-time 10 percent.
Circuit Description
The generator provides voltage to operate the vehicle's electrical system and to charge its battery. A
magnetic field is created when current flows through the rotor. This field rotates as the rotor is driven by
the engine, creating an AC voltage in the stator windings. The AC voltage is converted to DC by the
rectifier bridge and is supplied to the electrical system at the battery terminal.
When the engine is running, the {lenerator turn-on signal is sent to the generator from the ECM, turning
on the regulator. The generator's voltage regulator controls current to the rotor, thereby controlling the
output voltage. The rotor current is proportional to the electrical pulse width supplied by the regulator.
When the engine is started, the regulator senses generator rotation by detecting AC voltage at the stator
through an internal wire. Once the engine is running, the regulator varies the field current by controlling
the pulse width. This regulates the generator output voltage for proper battery charging and electrical
system operation. The generator F terminal is connected internally to the voltage regulator and externally
to the ECM. When the voltage regulator detects a charging system problem, it grounds this circuit to
signal the ECM that a problem exists. The ECM monitors the generator field duty cycle signal circuit. The
system voltage sense circuit receives B+ voltage that is Hot At All Times through the GEN BAT fuse in
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