Week #3 - Charging System Flashcards Preview

OTC - Diesel Electrical DET-106 > Week #3 - Charging System > Flashcards

Flashcards in Week #3 - Charging System Deck (22)
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1
Q

How many diodes are used in a typical alternator rectifier bridge?

A

6 (A typical alternator bridge used 6 diodes: some alternators use 2 rectifier bridges)

2
Q

True or False: An alternator rated at130 amps is carbon pile load tested and system voltage drops to 12.6 bolts at a current load of 120 amps. This means that the alternator is okay and can be returned to service.

A

True

3
Q

What is used to control the current output of an alternator?

A

A voltage regulator

4
Q

True or False: Intelli-check is an industry acceptable means of testing charging system performance.

A

True

5
Q

What part of an alternator produces the magnetic field?

A

Rotor

6
Q

What is the function of slip rings in an alternator?

A

To conduct current to the rotor

7
Q

When Intelli-check produces a good status rating, the charging system should still be further tested.

A

False

8
Q

What is the moving component in an alternator?

A

The rotor

9
Q

What instrument should be used to measure alternator current output?

A

An ammeter

10
Q

How much horsepower is required to drive a 100 amp alternator?

A

6-7 horsepower

11
Q

When the term sensing voltage is referred to in alternator operation, which of the following best describes it?

a. 5 volts AC
b. 5 volts DC
c. diode leakage voltage
d. battery voltage

A

d. battery voltage

12
Q

What is used to perform switching functions in an electronic voltage regulator?

A

Transistors

13
Q

A typical rotor contains:

a. a pair of poles, one north and one south
b. seven north poles and seven south poles
c. fourteen north poles and fourteen south poles
d. fourteen north poles or fourteen south poles

A

b. seven north poles and seven south poles

14
Q

What type of diode bridge arrangement is more common in alternators used in heavy truck applications?

A

Delta

15
Q

True or False: An alternator rated at130 amps is carbon pile load tested and system voltage drops to 12.6 bolts at a current load of 120 amps. The alternator output should test within 10 percent of the rated specification.

A

True (industry standard is within 10% specification)

16
Q

Why do the brushes in an alternator last much longer than brushes in a DC generator?

A

They conduct much less current

17
Q

When a carbon pile is used to lad the electrical system to test the charging circuit, how much load should be applied?

a. enough to drop system voltage to 9.6 volts
b. enough to drop system voltage to 12.7 volts
c. one-half the CCA rating of the batteries
d. the rated amperage specification

A

b. enough to drop the system voltage to 12.7 volts

18
Q

When a diode is in reverse bias, what is happening to current flow through it?

A

Current is blocked

19
Q

What is used in an alternator to rectify AC to DC?

A

Diodes

20
Q

How many windings are in a typical alternator stator?

A

3

21
Q

What component is used to switch field current on and off in an alternator?

A

A voltage regulator

22
Q

When an alternator is full-fielded, which of the following components is bypassed?

a. the voltage regulator
b. the stator
c. the rotor
d. the slip rings

A

a. the voltage regulator