Deck 8: Charging Systems

Question 1

Which of the following statements about how electrical current flow is induced in an alternator is correct?

A) rotating magnetic field induces a voltage into stationary windings
B) stationary magnetic field induces voltage within a rotor
C) current flow from the alternator is sourced from the battery banks
D) current flow from the alternator is sourced from the voltage regulator

Answer 1

A

Question 2

Which of the following defects could result in an undercharged battery?

A) loose belt(s)
B) defective diode trio
C) defective voltage regulator
D) all of the above

Answer 2

D

Question 3

How much current flows through the brushes and slip rings of an alternator?

A) the combined rated CCA current of the batteries
B) full output of the alternator
C) field current
D) whatever current can pass through the voltage regulator

Answer 3

C

Question 4

Which windings in an alternator are connected to the diodes in the rectifier?

A) field windings
B) stator windings
C) pull-in windings
D) hold-in windings

Question 5

Technician A says that to perform an AC leakage test,a DMM should be set to auto-range AC with one test lead placed on the alternator insulated terminal,and the other on chassis ground.Technician B says that when performing an AC leakage test,the engine should be run at 1500 rpm.Who is correct?

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

Question 6

Technician A says that most current trucks are protected from reverse polarity connections to the electrical system.Technician B says that by connecting a truck electrical system in reverse polarity can destroy an alternator diode bridge and other solid state devices.Who is correct?

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

Question 7

What is the maximum acceptable AC leakage specification in a typical truck charging system?

A) 0.1 V-AC
B) 0.3 V-AC
C) 0.5 V-AC
D) 1.0 V-AC

Question 8

How are the stator windings in a typical truck alternator configured?

A) wye connection
B) delta connection
C) twisted triad
D) semi-elliptical

Question 9

How many diodes are used in a typical 3-phase,full-rectification truck alternator?

A) 3
B) 6
C) 9
D) 12

Question 10

What component in an alternator rotates?

A) rotor
B) stator
C) rectifier
D) heat sink

Question 11

Which stator windings are connected in series and have a neutral junction?

A) wye-wound stator
B) delta-wound stator
C) both A and B
D) neither A nor B

Question 12

Technician A says that a TR type alternator is designed for 12/24-volt chassis electrical system.Technician B says that TR type alternators are commonly used on current,electronically-controlled high compression engines.Who is correct?

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

Question 13

When an alternator is full-fielded,which of the following temporarily ceases to function?

A) rectifier
B) rotor magnetic field
C) voltage regulator
D) stator

Question 14

Which of the following conditions will shorten the life of batteries?

A) overcharging
B) undercharging
C) deep-cycling
D) all of the above

Question 15

How is field current routed through an alternator?

A) through the stator only
B) through the rotor only
C) through slip rings and the stator
D) through slip rings and the rotor

Question 16

Technician A says that the best overvoltage protection system in a truck electrical system is the battery bank.Technician B says that zener diodes can be used to suppress voltage spikes that can occur in a truck electrical system.Who is correct?

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

Question 17

What specific component on a truck charging system does an AC leakage test evaluate?

A) stator
B) slip rings
C) diode bridge
D) rotor

Question 18

What is the function of the diode trio in an internally regulated truck alternator?

A) rectifies the current produced by the field coil
B) forms one half of the rectifier
C) performs voltage regulator switching
D) all of the above

Question 19

Which of the following statements about the diagnostic practice of full-fielding an alternator is true?

A) procedures for A- and B- type circuit regulated alternators are different
B) some internally regulated alternators can be full-fielded with a paper clip
C) some internally regulated charging systems cannot be full-fielded
D) all of the above

Question 20

Which of the following sets of voltage range specifications indicates that a typical truck voltage regulator is functioning properly?

A) 12.6-13.4 volts
B) 13.5-14.1 volts
C) 14.1-15.5 volts
D) 14.6-16.0 volts

Question 21

Which of the following describes the role of a rectifier in an alternator?

A) AC is rectified to DC
B) DC is rectified to AC
C) voltage is rectified to current
D) current is rectified to voltage

Question 22

Technician A says that the Delco-Remy Intelli-check instrument can pin-point difficult to diagnose,charging circuit problems.Technician B says that an Intelli-check test procedure produces one of 5 status outcomes after testing.Who is correct?

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

Question 23

Technician A says that a Delco/Remy 33/34 SI alternator can only be driven clockwise (CW).Technician B says that to restore residual magnetism in an alternator with an R or I terminal,the ground terminal should be momentarily connected to battery ground.Who is correct?

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

Question 24

Technician A says that to perform a maximum output test on a typical heavy-duty truck charging circuit,the engine should be run at 1500 rpm.Technician B says that alternator rpm is typically at least three times engine rpm.Who is correct?

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

Question 25

Technician A says that Intelli-check is best used as a first-level diagnostic tool.Technician B says that if Intelli-check illuminates one of the four failure indicator LEDs,it would be good practice to have a technician skilled in electrical systems to check the system before replacing components.Who is correct?

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

Question 26

What amperage ratings can be produced by a Delco/Remy 33/34 SI alternator?

A) 80 to 105 amps
B) 95 to 115 amps
C) 115 to 120 amps
D) 150 amps or more

Question 27

Technician A says that a Delco/Remy 55 SI alternator rated at 420 amps is often used in motor coach applications.Technician B says that a Delcotron 33/34 SI can be rated as high as 300 amps.Who is correct?

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

Question 28

How many windings should a typical truck alternator stator have?

A) one
B) two
C) three
D) six

Question 29

Technician A says that a 100 amp alternator can draw as much as 7 horsepower from the engine.Technician B says that an alternator is switched in and out of its effective cycle by the voltage regulator.Who is correct?

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

Question 30

Which of the following best explains how an alternator is driven by truck engine at a higher speed than engine rpm?

A) drive pulley to alternator pulley ratio
B) drive gear to alternator gear ratio
C) use of multiple drive pulley belts
D) internal gear multiplication in alternator

Question 31

When testing a Delcotron 33/34 SI alternator at an ambient temperature of 80 degrees Fahrenheit,what would be a within specification field current draw?

A) less than 1 amp
B) 2.0 to 2.5 amps
C) 5.5 to 9 amps
D) 12.0 to 12.6 amps

Question 32

Technician A says that when the load on a truck electrical system is minimal,the alternator will freewheel,reducing the parasitic load on the engine.Technician B says that a typical truck alternator may be cycled by the voltage regulator hundreds of times per second.Who is correct?

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

Question 33

If you do not apply an electrical load to the batteries when full-fielding an alternator,which of the following could result?

A) high voltage spikes
B) damage to electrical components
C) damage to electronic components
D) all of the above

Question 34

Which of the following alternator failures could result in undercharging?

A) shorted stator winding
B) open stator winding
C) grounded rectifier
D) all of the above

Question 35

When a diode is used in an AC circuit for half-wave rectification,which of the following should be true?

A) it becomes reverse bias to block the positive half of the AC sine wave
B) scrambles frequency of the AC sine wave
C) it becomes forward bias to conduct the positive half of the AC sine wave
D) square waves the sine wave