Charging system PT 1 • http://www.youtube.com/watch?v=oYTrbDLSy_w
Purpose • Purpose of charging system to keep battery at a fully charged state. • Provide power for all electrical loads • Alternator is the component that generates electricity to charge the battery.
Principle • The principle of electromagnetic induction to generate electrical energy from mechanical energy • Electromagnetic induction involves the generation of an electrical current in a conductor when the conductor is moved through a magnetic field.
How do we increase electricity • Demonstration with alternator on how electricity is generated. • How can we increase electricity
Increasing Current • Increasing the speed of the conductor through the magnetic field. • Increasing the number of conductors passing through the magnetic field • Increasing the strength of the magnetic field.
AC and DC • AC– Alternating current • DC– Direct Current • Alternator generates AC voltage. • Automotive battery and vehicle system using DC voltage.
AC and DC • So what changes the AC to DC voltage. • The voltage Rectifier. • Rectifiers are consisted with six diodes. • Diodes are one way check valves that only allow current to flow one way.
What is the proper system voltage? • 13.8 - 15 volts • 27.4 – 28.4 volts
What controls the system voltage? • Voltage regulator
Voltage Regulator • Controls the voltage output of the alternator. • The regulator receives system voltage as an input, in order to regulate alternator output voltage.
Charging System PT2 http://www.youtube.com/watch?v=Yv4t795Yb5k&feature=related
What can cause the charging system to under-charge? • Loose fan belt • Low engine RPM • Excessive load requirements (add on accessories)
What can cause the charging system to under-charge? • Short driving trips • Defective generator • Defective voltage regulator • Defective wiring
voltage trace on oscilloscope (diode pattern)
Stator Rectifier (Diode pack)
How does the voltage regulator control the A/C generator? • The regulator will turn on/off current to the field windings (rotor) • Increasing current to the rotor… • …will increase generator output
14 V 80 o F 1 V