Charging System Fundamentals Chapter 34 Page 449

The Alternator

System Diagram Battery Alternator

The Alternator

Locations Can Vary V- Belt Pulley Serpentine Belt Pulley

Parts Breakdown

Alternating Current (AC) The rotor is a shaft wrapped the wire, when a voltage is introduced– it produces an electromagnet The stator is a series of three wire wrappings that are stationary As the rotor turns in side the stator ring– current is induced (produced) making current flow

Magnetic Field

Rotor

Alternator Rotor and Magnetic Poles

Stator

Voltage Output Patterns Positive Negative All three windings One stator winding 13 -14 volts Converted to positive only!

Diodes One way check valve- allows current to flow in one direction but not in reverse This is how the negative voltage that is produced in the alternator is not allows to the battery. Sets are usually placed in a heat sink- they get extremely hot– the sink can dissipate this heat

Electrical Connection Brushes allow for contact with rotor Power is controlled from the ignition switch

Slip Rings and Brushes

The Fan Draws Air From the Rear Through to the Front Cooling Internal Components

Cooling Fan

Internal regulators are used in Voltage Regulator Maintain voltage between 13 and 15.5 volts Under 13 would not charge battery Over will overload the electrical circuits, especially computer controlled components. External voltage regulators were used until the 1980’s Internal regulators are used in many alternators On board computers have eliminated the need for regulators in today’s vehicles

Your Job. Complete chapter Questions 1-10 (review) and 1-5 (ASE-style). Page 457-458 Write on a separate paper and write out the complete question and your answer. ( do not write the other answer options). Complete the chapter worksheet (I will give it out). You may write on it. File all items in your note book. Notebooks will be graded in the future.