ELT 117 Final

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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


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