CAMSHAFT 4209998 - Caterpillar

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27-SI Alternator (1) Field Winding (2) Rotor (3) Stator (4) Regulator (5) Rectifier (6) Capacitor (7) Diode AssemblyField Winding
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Field winding (1) is a stationary coil that provides a magnetic field for the rotor.Rotor
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Rotor (2) consists of a magnetic core that is mounted on a shaft. The rotor rotates on the shaft. The rotor is magnetized by the field winding, and the rotor provides a magnetic field for the stator.The core is divided into two poles that are separated by an insulated ring. When current flows in the field winding, the core is magnetized. One side becomes the "N" pole, and the other side becomes the "S" pole.When the current in the field winding stops, the core does not lose the magnetism completely. The core still contains some residual magnetism.Stator
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Stator (3) consists of a stator core and three independent windings. As the rotor turns, a varying magnetic field causes the stator windings to produce three-phase AC voltage. The stator is supported by the front frame and by the rear frame.Rectifier
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Rectifier (5) is a three-phase full wave rectifier. The rectifier changes the AC voltage that is produced by the stator to DC voltage. The rectifier contains positive diodes and negative diodes. The DC voltage from the positive diodes and from the negative diodes is delivered to the battery terminals.Diode Assembly
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Diode assembly (7) contains three exciter diodes. The negative diodes from rectifier (5) and the exciter diodes change the AC voltage from the stator to DC voltage. The DC voltage from the exciter diodes and from the negative diodes energizes the field winding.Capacitor
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Capacitor (6) performs the following tasks:
The capacitor protects the rectifier diodes from high transient voltages.
The capacitor protects the diode assembly from high transient voltages.
The capacitor smooths the output of the rectifier.
The capacitor suppresses radio interference.
The capacitor reduces electrical noise.The capacitor is mounted inside the rear frame. The capacitor is connected to the rectifier.Regulator
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Regulator (4) limits the output voltage of the alternator to a preset value by controlling the current through the field winding. The regulator electronically switches the connection between the field coil and ground. The switching occurs at variable rates. The regulator is mounted inside the rear frame. The regulator is totally enclosed. The regulator cannot be adjusted.