ELT 117 Final
Shorted
In the shaded pole induction motor, the shading coil acts like a transformer with an _____ secondary
Series and shunt windings
A compound motor has _____ field windings
Motor
A device that converts electrical energy into mechanical energy is called
Compound
A generator containing both series and shunt fields is called a ____ generator
generator
A machine that converts mechanical energy into electrical energy
Hysteresis
A single phase synchronous motor is sometimes referred to as an _____ motor
synchronous condenser
A synchronous motor operated with no load and used for power factor correction is sometimes called a
90 degrees out of phase
A two phase power system has two voltages that are
Repulsion
An _____ motor operates on the principle that like magnetic poles repel
Synchronoscope
An _______ is used to measure the difference in voltage and frequency between two alternators
Brushless exciter
An alternator that has a separate small alternator mounted on the shaft of its rotor is equipped with an ______
Wave-Wound Armatures
Armatures are wound to provide high voltage, high current, or some specific combination of voltage and current. The winding that provides high voltage and low current
sliprings
Connection to the armature of an alternator is normally done by using
armature, shunt field
In a compound DC motor control circuit, the field loss relay will disconnect the _____ if power is lost to the _____
Series field shunt rheostat
In a generator, the ________ permits part of the current that normally flows through the series field to flow through the resistor.
Synchronous speed
In a motor that has a rotating magnetic field, the speed of the magnetic field is referred to as the
Synchronous
In a three phase motor, the speed of rotation of the magnetic field is called _____ speed
Hydrogen
In order to increase the efficiency of the cooling, some alternators operate in the atmosphere of
Centrifugal switch
In single phase motors suck as the resistance start induction run motor, the start winding is disconnected by the
Cut in half
In the consequent pole motor, if the number of poles is doubled, the motor speed will be
Magnetic field strength
In the shaded pole induction motor, the direction of rotation of the magnetic field is determined by the
Brushes
Rides against the commutator segments and are used to connect the armature to the external circuit of the DC machine
Series
The series generator has only a series field, which is connected in _____ with the armature
ServoDisc motor
The servomotor which has fiberglass and copper rotor is the
Amortisseur Winding
The set of squirrel cage bars on the rotor of a synchronous motor is used to start the motor and is known as
Pulse Width
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
0 degrees
The torque of a squirrel cage induction motor will be maximum when the phase angle between the stator and rotor fields is
Differential compound
A compound generator has both series and field windings. When those windings are connected so their fields oppose each other in the production of magnetism, that connection is called
Cumulative compound
A compound generator has both series and shunt field windings. When those windings are connected so they aid each other in the production of magnetism, that connection is called
Lap wound armatures
Armatures are wound to provide high voltage, high current, or some specific combination of voltage and current. The winding that provides low voltage and high current
Frogleg-Wound Armatures
Armatures are wound to provide high voltage, high current, or some specific combination of voltage and current. The winding that provides moderate voltage and moderate current
Air and hydrogen
Because some of the input energy to the alternator ends up being converted into heat, often cooling is required. The main types of cooling media are
2 to 5
For most squirrel cage motors the typical percent slip is about _____ percent
Parallel
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
Inductance
Multispeed fan motors achieve multiple speeds by inserting additional ______ in series with the run winding
Alternators
Operate on the same principle of electromagnetic induction as DC generators, but they have no commutator
higher
Permanent magnet motors have ____ efficiency than conventional field wound motors
Pole pieces
Provides the magnetic field necessary for the operation of the machine
Two
The consequent pole motor is an ______ speed motor
few, large
Series field windings are connected in series with the armature. They are wound with _____ turns of fairly _____ wire
Brushless DC
The motor that does not contain a wound armature, commutator, or brushes is the
Stator
The non rotating part of an alternator is called the
Field discharge resistor
Using an ______ is one method of preventing induced voltage from becoming excessive
Shunt field
When a motor is connected differential compound, the _____ determines the direction of rotation of the motor at no load or light load
Several times the running current
When a squirrel cage motor is first started, the value of the current draw is
Shunt motor
When the field winding of a DC motor is connected in parallel with the armature, it is called
Series
Some motors are constructed so that they will operate on either of two voltages. When they are connected to operate on the higher or the two voltages, the windings are connected in _______
Parallel
Some motors are constructed so that they will operate on either of two voltages. When they are connected to operate on the lower or the two voltages, the windings are connected in _______
Rotating
Split phase motors operate on the principle of ______ magnetic field
Shunt motor
The DC motor, known as a "constant speed motor" is the _____ motor
Printed circuit
The ServoDisc motor is also often called a _____ motor
Run
The ____ winding is made of few turns of large wire and is located at the bottom of the stator core
Universal
The _____ motor can operate on either AC or DC voltage
Start
The _____ winding is made of many turns of small wire and is located at the top of the stator core
Commutator
The component of a DC generator that converts the armature AC into DC
Differential compound
The compound motor connection that should generally be avoided is the
Three windings connected in wye
The differential seslyn has three stator windings connected in wye and a rotor made of
Excitation
The direct current that is an input to the alternators rotor is the ______ current
Phase
The direction of the magnetic field rotation is known as _____ rotation
field
The higher power output alternators use a revolving
Compensating winding
The universal motor has a wound armature and brushes like a AC motor, as well as an added component, the
High, low
The wound rotor induction motor is popular on industry because it has ______ starting torque and ______ starting current
Any two leads
To reverse the direction of rotation of a three phase motor, reverse
Moves through specific angle for each input pulse
The output shaft of a stepping motor
Single phase
Seslyn motors operate on _____ voltage
Armature resistance
The speed regulation of a DC motor is proportional to the _______.
Starting torque
The squirrel cage rotor code letters indicate the shape of rotor bars. Different types of bars have a large effect on the ______ of a motor
Single phasing
Three lines supply power to a three phase motor. If one of these lines should open, the motor will be connected to a single phase power. This condition is called
Maximum
In a universal motor, setting the brushes to the neutral plane can be done by connecting voltage to the armature, a voltmeter to the compensating winding, and adjusting the brush position for a ______ reading on the voltmeter
Minimum
In a universal motor, setting the brushes to the neutral plane can be done by connecting voltage to the armature, a voltmeter to the series field, and adjusting the brush position for a ______ reading on the voltmeter
many, small
Shunt field windings are connected in parallel with the armature. They are wound with _____ turns of fairly _____ wire
Parallel
Shunt generators contain only a shunt field winding connected in ____ with the armature
Servomotors
Small permanent magnet motors that have lightweight rotors are often used as ________.
Number of stator poles and rotor rotation speed
The output frequency of an alternator is controlled by the
Field excitation current
The output voltage of a generator is usually controlled by the amount of
3V
The positive pulses are 25 wide and there is 75 gap between them. What is the DC average of the waveform
6V
The positive pulses are 50 wide and there is a 50 gap between them. What is the DC average of the waveform
9V
The positive pulses are 75 wide and there is a 25 gap between them. What is the DC average of the waveform
Compounding
The relationship of the strengths of the two fields in a generator determines the amount of
Less, less
The revolving armature type of alternator is capable of ______ power output and is, therefore, ______ often used than the revolving field type
Armature
The rotating part of an electrical generator.
Bars, rings
The squirrel cage rotor is constructed of ______ and end ______ embedded in steel laminations
Rotor
The rotating part of an alternator is called the