the strength of the rotating magnetic field in a small aircraft is controlled by the amount of _____ flowing in the rotor windings
current
individual diodes in an alternators rectifier assembly may be tested for opens or shorts by using an
ohmmeter
if the battery is removed from the aircraft and the engine is started by means of hand propping, will the small aircraft alternator have an output voltage
no, because the alternator has no residual magnetism
in a small aircraft alternator circuit the _____ battery current from flowing to the alternator stator windings
full wave rectifier assembly
the two types of three phase alternator winding configurations are
y and delta
a stationary winding of an alternator is called a
stator
grounding of the field terminal on a small aircraft alternator equipped with a transistor voltage regulator while the system in operation will most likely result in
damage to the regulator
the resistance reading when testing an alternator rotor for a 12 volt system, should be between
3 to 5 ohms
it is reported that the charging system on an aircraft with a 12 volt alternator does no show an output. a voltmeter connected from the positive terminal on the alternator to the ground reads battery voltage. you temporarily connect a jumper from the posi
voltage regulator
what repairs may a mechanic make to a solid state voltage regulator
the mechanic does not make repairs to the solid state regulator
a loose alternator drive belt would cause
a low output from the alternator due to belt slippage
a three phase full wave rectifier assembly consists of _____ diodes
six
you are testing an alternator rotor with an ohmmeter. when the probes of the ohmmeter are placed on the slip rings of the rotor the ohmmeter reads infinity ohms, it is an indication of
open circuit in rotor windings
when testing alternator diodes with an ohmmeter and open diode is indicated by
resistance in both directions
what method is used to conduct current from the voltage regulator to the rotating field in a small aircraft alternator?
brushes and slip rings
while checking an alternator with a voltmeter, on a small aircraft with the engine running, you short terminals battery positive to f, this would cause
excessive voltage output from the alternator
what device is used as a voltage sensing unit in the transistor voltage regulator and control the bias on the control transistor TR2?
zener diode
arcing at the brushes and burning of the commutation of a generator may be caused by ______
weak brush springs
while operating a generator with a vibratory type voltage regulator, the points stick closed. this would cause _____
a big increase in generator voltage output
if a generator is equipped with a vibrator type voltage regulator, the actual time the voltage regulator points remain closed _____
depends on the load carried by the generator
when generators are connected in parallel, they must be paralleled so that _____
each generator will share the load equally
the mica insulation between the segments of a generator commutation should be undercut approximately ______
.020 inches
often, aircraft generators have bearing of the ______
ball type
occasionally, a generator loses its residual magnetism, when this occurs the next time the generator is operated, it will ____
fail to generate voltage
whbyat value of reverse current will make a 12 volt system reverse current relay open its contact points?
5 to 10 amps
what is a cause of generator brush arcing?
low spring tension
the method most often used to overcome the effects of armature reaction is through the use of
interpoles
a generator is classified as a b type, this means the regulator ______
is in the positive side of the field coils
a voltage regulator controls generator output by _____
varying current flow to generator field coil
what type of rectifier is used to change alternator output to direct current?
a three phase, full wave, solid state
how are generators rated?
Amperes at rated voltage
the generator rating is usually found stamped in the _____
generator data plate
residual voltage from a generator is a result of _______
magnetism in the field poles
______ DC generators are not used as an airplane generator.
series wound
_____ is the method used for restoring generator field residual magnetism.
flashing the fields
what is the purpose of a reverse current cutout relay?
It opens the main generator circuit whenever the generator voltage drops below the battery voltage to prevent the battery from discharging through armature
as the flux density in the field of a DC generator increases and the current flow to the system increases, ______
the force required to turn the generator increases
_____ is not one of the purposes of interpoles in a generator
reduce field strength
in a vibrator type generator, if the contact points remained open, the voltage would _____
decrease
in a generator, electrical current is transferred from the commutator the the output terminals by _____
brushes
a lathe is used during generator maintenance to ______
turn down and clean up a badly pitted or damaged commutator
when installing a new ball bearing on the armature shaft, the bearing should have force applied _____
on the inner race only
a growler is used for testing _______
armature of generators and motors
commutators or slip rings may be polished with _____
000 sandpaper or crocus cloth
a generator vibrator type voltage regulator should be final adjusted for correct voltage output _____
on the aircraft after the generator has been warmed up and using a calibrated precision voltmeter
what causes the points of a reverse current cut out relay to close
when the generator voltage rises to a predetermined value, the shunt winding will close the points
what method is used to seat newly installed generator brushes?
by a 5 hour run in or an abrasive stick
regulated output voltage of a generator with a vibrator type voltage regulator is adjusted by _______
adjusting spring tension
regulated output voltage of an alternator with a transistorsized voltage regulator is adjusted by _______
adjusting spring tension
regulated output voltage of an alternator with a transistor voltage regulator is adjusted by ______
adjusting the potentiometer