Chapter 8 (assessment)

Question 1

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

Answer 1

0.3 V-AC

Question 2

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?

Answer 2

Technician B only

Question 3

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?

Answer 3

Both A and B

Question 4

Which of the following alternator failures could result in undercharging?
a) opens stator winding
b) shorted stator winding
c) grounded rectifier
d) all of the above

Answer 4

all of the above

Question 5

How is field current routed through an alternator?

Answer 5

through slip rings and the rotor

Question 6

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

Answer 6

AC is rectified to DC

Question 7

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

Answer 7

rotating magnetic field induces a voltage into stationary windings

Question 8

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

Answer 8

wye-wound stator

Question 9

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

Answer 9

it becomes forward bias to conduct the positive half of the AC sine wave

Question 10

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?

Answer 10

Technician B only

Question 11

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

Answer 11

stator windings

Question 12

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?

Answer 12

Technician B only

Question 13

Which of the following conditions will shorten the life of batteries?
a) undercharging
b) overcharging
c) deep-cycling
d) all of the above

Answer 13

all of the above

Question 14

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

Answer 14

rectifies the current produced by the field coil

Question 15

What component in an alternator rotates?

Answer 15

rotor

Question 16

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?

Answer 16

Both A and B

Question 17

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

Answer 17

all of the above

Question 18

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

Answer 18

13.5-14.1 volts

Question 19

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

Answer 19

drive pulley to alternator pulley ratio

Question 20

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?

Answer 20

Both A and B

Question 21

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

Answer 21

voltage regulator

Question 22

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

Answer 22

150 amps or more

Question 23

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?

Answer 23

Both A and B

Question 24

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

Answer 24

6

Question 25

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?

Answer 25

5.5 to 9 amps