Alternators Flashcards
When an ohmmeter is connected with one lead to a slip ring and the other to the rotor shaft, a reading of 3 ohms would indicate the rotor is:
a. Open
b. Shorted
c. Grounded
d. OK
c. Grounded
When an ohmmeter is connected with one lead to each of the slip rings and the resistance reading is below specs, the rotor is:
a. Shorted
b. Open
c. Grounded
d. OK
a. Shorted
With one ohmmeter lead connected to the stator lead and the other connected to the iron laminations, an infinite reading indicates that the stator is:
a. Open
b. Grounded
c. Shorted
d. OK
d. OK
By grounding the tab in the back of the Delco integral regulator alternator, we achieve maximum output by:
a. Grounding the sensing circuit
b. Grounding the field
c. Opening the field
d. Grounding the stator
b. Grounding the field
A Delta would stator can produce more current than a Y wound stator because the Delta windings are:
a. Longer
b. Heavier
c. In series
d. In parallel
d. In parallel
A serviceable diode is indicated by [blank] analog ohmmeter readings.
a. Two low
b. Two high
c. One high and one low
d. Two zero
c. One high and one low
In many alternators, the diodes are assembled in a component called a (an):
a. Rectifier bridge
b. Regulator bridge
c. Diode housing
d. Insulator block
a. Rectifier bridge
To bypass the voltage regulator in a “B” type charging system, the mechanic must:
a. Ground the field
b. Isolate the field relay
c. Supply 12 volts to the R terminal
d. Supply 12 volts to the F terminal
d. Supply 12 volts to the F terminal
In an “A” circuit charging system, the voltage regulator is located between the:
a. Ignition switch and the field coil
b. Battery and the field coil
c. The field coil and the sensing circuit
d. The field coil and ground
d. The field coil and ground
In an alternator, output regulation is achieved by varying:
a. Field current
b. Speed
c. Stator current
d. Magnetic polarity
a. Field current
Some transistorized voltage regulators incorporate a [blank] to vary voltage according to temperature.
a. Thyristor
b. Potentiometer
c. Capacitor
d. Thermistor
d. Thermistor
If a battery were connected with the positive terminal to the “P” material and the negative terminal to the “N” material, the diode is said to be:
a. Forward biased
b. Reverse biased
c. A zener diode
d. Open circuited
a. Forward biased
In order for current to flow through the emitter collector circuit of a PNP transistor, we must provide the base with:
a. A ground
b. “+” voltage
c. A specified resistance
d. All of the above
a. A ground
Circuit application of NPN transistors require the base to be connected to:
a. A ground
b. “+” voltage
c. A specified voltage
d. All of the above
b. “+” voltage
A “B” circuit alternator most often will have:
a. Two field terminals
b. Two insulated terminals
c. One internally grounded brush
d. An “R” terminal
c. One internally grounded brush
When an ammeter is placed in series with the slip rings and an attached 12 volt battery, we could measure:
a. Field draw
b. Voltage drop
c. Field pressure
d. Charging amperage
a. Field draw
The magnetic draw of an alternator is created in the:
a. Stator
b. Rectifier
c. Rotor
d. Bearings
c. Rotor
Alternator brushes must carry approximately [blank] amperes.
a. 1 to 2
b. 2 to 6
c. 10 to 36
d. 36 to 50
b. 2 to 6
When checking an alternator diode trio, if an ohmmeter reads low ohms in both direction on one leg, the diode is:
a. Okay - normal
b. Defective - shorted
c. Okay - open
d. Defective - open
b. Defective - shorted
Warning lamps are installed so that they will not light when:
a. The voltage on the battery side of the lamp is higher
b. Field current is flowing from the battery to the alternator
c. The voltage on both sides of the lamp is equal
d. None of the above
b. Field current is flowing from the battery to the alternator
The voltage regulator in an alternator charging system is a device that controls:
a. Maximum voltage output
b. Voltage output
c. Current output
d. Minimum voltage output
b. Voltage output
A probable cause of undercharging is:
a. A field wire is shorted
b. A sulphated battery
c. High resistance between the battery and fuse block
d. Low resistance in the alternator field circuit
b. A sulphated battery
The first step in inspecting the charging system is to:
a. Replace the alternator drive belt
b. Remove the alternator
c. Check the battery conditions
d. Check system voltage
c. Check the battery conditions
There should be battery voltage available at the alternator output terminal:
a. At all times
b. When the ignition is switched on
c. When the engine is running
d. If the regulator is defective
a. At all times
Manufacturers often recommend a voltage output test, rather than a current output test to prevent:
a. System overloading
b. Electronic component damage
c. Alternator damage
d. Wiring damage
b. Electronic component damage
Which of the following is NOT a typical alternator bench test?
a. Rotor continuity test
b. Stator ground test
c. Growler test
d. Diode test
c. Growler test
If a self powered test light does not light when connected to both slip rings of a rotor, the winding is:
a. Open
b. Good
c. Shorted
d. Grounded
a. Open
If an ohmmeter reading is low when connected between each pair of stator leads, the winding is:
a. Open
b. Good
c. Shorted
d. Grounded
c. Shorted
An alternator oscilloscope trace that shows a series of equally spaced and equal sized pulses indicates:
a. An open diode
b. A grounded diode
c. A good stator and diode
d. A weak capacitor
c. A good stator and diode
When checking diode resistance by reversing the leads of an ohmmeter, a good diode produces:
a. Two low readings
b. Two high readings
c. One high and one low reading
d. One high and one infinite reading
c. One high and one low reading
Alternator charging systems are generally regulated to produce a maximum output of:
a. 12.6 volts
b. 13.6 volts
c. 14.6 volts
d. 15.6 volts
c. 14.6 volts
The magnetic field of an alternator is carried in the:
a. Stator
b. Rotor
c. Housing
d. Slip ring
b. Rotor
The output of an alternator is created in the:
a. Stator
b. Rotor
c. Housing
d. Brushes
a. Stator
An alternator stator with three windings usually has:
a. 3 diodes
b. 6 diodes
c. 9 diodes
d. 12 diodes
b. 6 diodes
Tech A says a source of current for the alternator field is the battery.
Tech B says a source current for the alternator output?!?
Who is correct?
a. A only
b. B only
c. Both A and B
d. Neither A nor B
c. Both A and B