Deck 7: Charging Systems

Question 1

The greater the number of magnetic lines of force that are cut by a conductor per second, the greater the voltage that is induced in the conductor.

Answer 1

True

Question 2

The number of times that a waveform repeats per second is referred to as the frequency.

Answer 2

True

Question 3

The ON time of a PWM signal is referred to as the duty cycle.

Answer 3

True

Question 4

The output of the diode trio is connected to the alternator positive output voltage terminal.

Question 5

A loss of residual magnetism of the rotor pole pieces can prevent an alternator from producing voltage.

Question 6

A brushless alternator would not have slip rings.

Question 7

Pulse width modulation is typically used to control rotor field current.

Question 8

The component which converts AC voltage into DC voltage in a modern alternator is the rectifier (bridge).

Question 9

The term used to describe a voltage trace in relationship to time with other voltage traces is ____?

A) phase
B) frequency
C) duty cycle
D) ripple

Question 10

Technician A says that the best way to determine if the alternator is charging the batteries with an electronically controlled diesel engine is to disconnect the positive battery cable with the engine running and determine if the engine dies. Technician B says that on a 12V system, the batteries should have an open circuit voltage measurement of less than 12.2V before performing any charging system testing. Who is correct?

A) A only
B) B only
C) Both A and B
D) Neither A nor B

Question 11

The ______ and ______ provide electrical contact with the rotor.

A) stator, field
B) slip rings, brushes
C) poles, brushes
D) windings, armature

Question 12

Technician A says that too high of a charging voltage can reduce battery life. Technician B says that too low of a charging voltage can reduce battery life. Who is correct?

A) A only
B) B only
C) Both A and B
D) Neither A nor B

Question 13

The remote sense terminal of an alternator would most likely be connected to the ____?

A) battery negative terminal
B) battery positive terminal
C) alternator ground
D) excitation terminal

Question 14

Technician A says alternator drive belt tension should be as tight as possible to prevent the belt from slipping. Technician B says that a high parasitic load could cause discharged batteries. Who is correct?

A) A only
B) B only
C) Both A and B
D) Neither A nor B

Question 15

Which of the following is a true statement?

A) The slip rings are connected to the stator.
B) All truck alternators have delta-wound stators.
C) The output of the stator windings is an AC voltage.
D) All of the above are true statements.

Question 16

A technician is testing a rectifier bridge using a DMM in the diode test mode. She measures 0.7V when each diode is forward biased and the DMM indicates OL when each diode is reverse biased. What do these test results indicate?

A) The results indicate the rectifier bridge is defective because of the OL indication when each diode is reverse biased.
B) The results indicate that this is definitely a positive rectifier bridge.
C) The results indicate she is not testing the rectifier bridge correctly.
D) The results indicate that none of the diodes in the rectifier bridge are shorted or open.

Question 17

Technician A says that a DMM ohmmeter is used to test an internal voltage regulator. Technician B says that the engine camshaft typically rotates at a higher speed than the alternator. Who is correct?

A) A only
B) B only
C) Both A and B
D) Neither A nor B

Question 18

The charging voltage is 16V on a truck with a 12V electrical system. What could be the possible cause(s)?

A) Excessive resistance in the remote voltage sense circuit
B) Incorrect adjustment of an adjustable voltage regulator
C) Defective voltage regulator
D) All of the above could cause this problem.

Question 19

The four main components of an alternator rotor are the pole pieces, the shaft, the field coil, and the ____.

A) stator
B) slip rings
C) rectifier
D) frame

Question 20

Which alternator component would most likely be damaged after the batteries were connected with reverse polarity?

A) Brushes
B) Field coil
C) Stator windings
D) Rectifier diodes