MOTORS, GENERATORS, ALTERNATORS
The rotating part of a generator is called the _____.
armature
The squirrel-cage rotor is constructed of _____ and end _____ embedded in steel laminations.
bars; rings
An alternator that has a separate smaller alternator mounted on the same shaft is a _____ type alternator.
brushless
The motor that does not contain a wound armature, commutator, or brushes is the _____ motor.
brushless DC
In the consequent pole motor, if the number of poles is doubled, the motor speed will be _____.
cut in half
t/f The synchronous motor is an induction motor.
false
Permanent magnet motors have _____ efficiency than conventional field-wound motors.
higher
A device that converts electrical energy into mechanical energy is called a(n) _____.
motor
Which of the following control the output frequency of an alternator?
number of stator poles, rotor rotation speed,
The speed of the disc servomotor can be varied by changing the amount of voltage supplied to the armature. The voltage is generally varied using _____modulation.
pulse-width
In a compound DC motor control circuit, the field loss relay will disconnect the armature if power is lost to the _____ field.
shunt
The DC motor, known as a "constant speed motor," is the _____ motor.
shunt
When the field winding of a DC motor is connected in parallel with the armature, the motor is called a _____ motor.
shunt
When a motor is connected differential compound, the _____ determines the direction of rotation of the motor at no load or light load.
shunt field
t/f Air-cooled alternators have a fan attached to one end of the shaft.
true
t/f When a squirrel-cage motor is first started, the value of the current draw is several times greater.
true
A generator containing both series and shunt fields is called a _____ generator.
compound
For most squirrel-cage induction motors the typical percent slip is about _____ percent.
2 to 5
The ServoDisc motor is also often called a _____ motor.
printed-circuit
The rotating part of a revolving-armature-type alternator is called the _____.
rotor
A compound motor has both _____ and ______ field windings.
series, shunt
Some motors are constructed so that they will operate on either of two voltages. When they are connected to operate on the higher of the two voltages, the windings are connected in _____.
serires
Counter-electromotive force (CEMF) and back-EMF are names for the unwanted voltage induced into the _______ coils of a DC motor.
armature
The speed regulation of a DC motor is proportional to the _____.
armature resistance
The frequency of the current in a squirrel-cage rotor _____ as the rotor approaches synchronous speed.
decreases
t/f A series motor may be operated with no load connected.
false
If one alternator does not produce sufficient power to supply a load, another alternator can be connected to the circuit. The second alternator is connected in _____ with the other generator.
parallel
Some motors are constructed so that they will operate on either of two voltages. When they are connected to operate on the lower of the two voltages, the windings are connected in _____.
parallel
The direction of magnetic field rotation is known as _____ rotation.
phase
What provide(s) the magnetic field necessary for the operation of a DC machine? (two words)
pole pieces
Three lines supply power to a three-phase motor. If one of these lines should open, the motor will be connected to single-phase power. This condition is known as _____.
single-phasing
The squirrel-cage rotor code letters indicate the shape (type) of rotor bars. Different types of bars have a large effect on the _____ of a motor.
starting torque
The non-rotating part of a revolving-field-type alternator is called the _____.
stator
If a piece of machinery needs a replacement motor and will be damaged if the new motor rotates the wrong way. The test equipment needed to test the rotation direction of the new motor is a _____.
phase rotation meter
The output voltage of a generator is usually controlled by the amount of _____ current. (two words)
field excitation
What is a device that converts mechanical energy into DC electrical energy? (one word)
generator
Small permanent magnet motors that have lightweight rotors are often used as _____.
servomotors
The servomotor featuring a fiberglass and copper rotor is the _____ motor.
ServoDisc
The torque of a squirrel-cage induction motor will be maximum when the phase angle between the stator and rotor fields is _____.
0 degrees
A motor is operating at 3450 RPM and is producing a torque of 32 lb-in. What is the output horsepower of the motor?
1.75 hp
To reverse the direction of rotation of a three-phase motor, reverse _____.
any two leads
