Quiz charging Flashcards
A fully charged battery should have a specific gravity of:
1.260 - 1.280
1.240 - 1.260
1.200 - 1.220
1.220 - 1.240
1.260 - 1.280
The open circuit voltage of a 24 volt electrical system would be:
24.0 v
28.0 v
25.2 v
29.6 v
25.2 v
When performing a high rate discharge test on a 12 volt battery, it should be loaded to _______________ of it’s cold cranking amps for ___________________ seconds and the voltage should not fall below ________________ volts when the battery is at 800 F.
1/2, 15, 9.6
1/2, 20, 8.5
1/3, 30, 10.2
3/4, 20, 10.5
1/2, 15, 9.6
The cold cranking ampere rating of a battery:
Indicates the ability of a battery to produce 25 amperes of current and maintain a minimum individual cell voltage of 1.75v
Indicates the ability of a battery to produce a certain amount of current for a period of 30 seconds while maintaining an individual cell voltage of 1.2v
Indicates the ability of a battery to produce 25 amperes of current and maintain a minimum individual cell voltage of 1.2v
Indicates the ability of a battery to produce a certain amount of current for a period of 30 seconds while maintaining a minimum cell voltage of 1.75v
Indicates the ability of a battery to produce a certain amount of current for a period of 30 seconds while maintaining an individual cell voltage of 1.2v
An open circuit voltage test on a battery group shows 23.4 volts. Your next step would be to:
Replace both batteries
Charge the batteries
Proceed with battery testing
Turn on the electrical loads for 3 minutes
Charge the batteries
The amperage in a series circuit is:
always the same at certain points
never the same anywhere
sometimes the same, under some conditions
always the same anywhere
always the same anywhere
The sum of the voltage drops in a series circuit equals:
the source voltage of the circuit
the amperage of the circuit
the resistance of the circuit
the shunt circuit voltage
the source voltage of the circuit
An ammeter is connected in a circuit in _________________.
reverse bias
series
series parallel
parallel
series
A good description of a ground fault in a circuit would be:
a bare wire touching a terminal
a conductor touching a frame rail
a high resistance connection
a broken wire or conductor
a conductor touching a frame rail
To find the voltage drop across a resistance in a circuit:
the resistance must be removed from the circuit.
current must be flowing in the circuit.
connect the voltmeter in parallel with the source voltage.
connect the voltmeter in series with a resistance.
current must be flowing in the circuit.
The pressure or force that causes electrons to flow can best be described as:
The pressure or force that causes electrons to flow can best be described as:
voltage
amps
ohms
capacitance
voltage
Diode polarity is determined by the:
method it was manufactured.
charging alternator polarity.
way it is connected in the circuit.
vehicle battery polarity.
method it was manufactured.
A ______________ is a device which will remove transient voltage that causes unwanted noise on radio frequencies.
Capacitor
Transistor
Thermistor
Diode
Capacitor
When a good diode will not conduct current, it is said to be__________________.
short circuited
reverse biased
forward biased
open circuited
reverse biased
Ampere multiplied by voltage will equal:
Reluctance
Amperage
Watts
Resistance
Watts
When soldering alternator connections, why are long nosed pliers used to hold the diode leads?
to prevent stator core damage
the pliers act as a heat sink.
to prevent overheating the stator windings
to prevent end frame damage
the pliers act as a heat sink.
Which of the following electrical devices uses a small current to control a larger current?
relay
all answers are correct
solenoid
magnetic switch
all answers are correct
How many diodes are needed to achieve half wave rectification?
3
depends on voltage
6
1
1
If a conductor is moved thru a magnetic field:
heat is generated
magnetism is increased
magnetism is reduced
voltage is generated
voltage is generated
The alternator component which smooths out the voltage pulsations in the system is the:
rectifier bridge
diode trio
capacitor
rotor field
capacitor
The part which produces the magnetic field in the rotor is the:
diode trio
rectifier bridge
field coil
stator
field coil
On an air-cooled alternator, air is drawn past the ________________________ first.
rotor
stator
heat sinks
field coils
heat sinks
In a “brushless” alternator:
the brushes are outside the housing
the field coil is stationary
the rotor is stationary
the stator is what revolves
the field coil is stationary
The function of slip rings is to:
carry field current to the field coil.
carry rectified voltage to the regulator.
reverse the direction of flux lines at the rotor turns.
carry induced voltage to the battery connection.
carry field current to the field coil.
The greatest induced voltage in a coil occurs:
when the conductors are parallel to the magnetic field.
when the conductors are parallel to 180 to the magnetic field.
when the conductors are at 90 to the magnetic field.
when the conductors are opposite the magnetic field.
when the conductors are at 90 to the magnetic field.
The constant change of the voltage as the rotor and it’s magnetic field are rotated first to a positive peak and the to a negative peak produces:
a sine wave voltage signal.
a digital signal
a DC voltage signal.
an analog signal.
a sine wave voltage signal.
In an alternator, alternating current is converted to direct current by the:
rectifier
stator
regulator
rotor
rectifier
The stator core is laminated to:
reduce heat producing eddy currents.
make it more permeable.
concentrate magnetic flux lines.
make it less permeable.
reduce heat producing eddy currents.
It requires __________________ diodes to achieve full wave, three phase rectification.
4
6
10
1
6
Which of the stator designs shown below is capable of producing higher current output ?
Delta type
Once the alternator has started to produce current, the AC field current can be drawn from the stator. This current is rectified by the:
positive diode group.
insulated heat sink.
diode trio.
negative diode group.
diode trio.
The maximum alternator output is limited by:
inductive reactance
current carrying capacity of the brushes
rotor field coil reluctance
size (gauge) of the stator winding
inductive reactance
The maximum alternator output is limited by:
inductive reactance
current carrying capacity of the brushes
rotor field coil reluctance
size (gauge) of the stator winding
inductive reactance
The maximum alternator output is limited by:
inductive reactance
current carrying capacity of the brushes
rotor field coil reluctance
size (gauge) of the stator winding
inductive reactance
Electrical current leaving the stator must pass through the:
stator.
rectifier.
rotor.
slip rings.
rectifier.
Electronic regulators operate on the principle of varying the on and off time that current is sent to the rotor coils. This method of varying an electrical flow in a circuit is known as:
pulse width modulation
potentiometer control
variable timed signal
analog signal generation
pulse width modulation
An electronic regulator in an “A” type field controls the rotor current by switching:
the stator resistance.
the rotor resistance.
the power side.
the ground side.
the ground side.
The voltage regulator controls the:
rotor current.
battery current.
stator resistance.
rotor resistance.
rotor current.
When using an ammeter to measure field coil current, a reading greater than normal would indicate:
a short to ground
an open circuit
excessive resistance
a short circuit
a short circui
When the field coil of an alternator is supplied with battery voltage, the alternator is said to be:
full fielded
full grounded
fully powered
at saturation
full fielded
A shorted diode in an alternator will result in:
reduced output amperage
not affect output but will reduce cooling air flow
reduced rotor resistance
have only a very slight reduction in output
reduced output amperage
If you have decided that low alternator output is the cause of a battery being discharged, your first check should be
stator
diodes
brushes
belts
belts
If the alternator starts to charge when the regulator is bypassed, what is probably at fault?
Alternator
Batteries
Supply wiring
Regulator
Regulator
After some heavy duty alternators are overhauled it is important to re-establish the rotor magnetism. This is accomplished by momentarily connecting a jumper lead from the battery to the:
negative post to the output terminal.
positive post to the output terminal.
positive post to the relay terminal.
negative post to the relay terminal.
positive post to the relay terminal.
Alternators are self limiting with regard to:
speed of the rotor.
speed of the stator.
current.
voltage.
current.
An alternator must never be operated with an open circuit as it may:
damage the stator assembly.
burn out the field relay.
damage the rectifiers.
damage the slip rings.
damage the rectifiers.
The maximum charging system voltage for a 24 volt system is:
24.0 v
29.6 v
28.4 v
30.2 v
29.6 v
Unwanted resistances that are found in insulated and ground alternator circuits will cause:
increased amperage flows.
increased power draws.
all given answers are possible
increased voltage loss.
increased voltage loss.
What can cause an alternator drive belt to fall apart in layers?
Excessive belt tension.
A worn alternator pulley.
Overheating due to belt slipping.
Engine oil.
Engine oil.
Two 12 volt batteries connected in series will provide:
24 v
12 v
24 v
The voltage regulator directly controls:
stator current
output current
field current
rectification
field current
In the diagram below, what checks are being made to the regulator?
Regulator grounds.
Regulator current capacity.
Regulator turn on voltage.
Regulator resistance.
Regulator turn on voltage.
In the diagram below, what checks are being made directly to the rotor?
Rotor grounds.
Stator resistance
Rotor short circuit
Rotor capacity
Rotor short circuit
