Untitled document (2)

Question 1

What type of motor has three sets of three leads?

Answer 1

Delta-connected motor

Question 2

In a DC motor, what does the armature do?

Answer 2

Turns and cuts through the lines of magnetic force produced by the field poles

Question 3

According to NEMA definitions, which of the following is a type of totally enclosed motor?

Answer 3

Water cooled

Question 4

NEC Article 430 covers _____

Answer 4

Application and installation of motors

Question 5

Several motors are permitted to be supplied by a single branch circuit as long as _____

Answer 5

Each motor is no larger than 1 horsepower

Question 6

Which application is MOST likely to use dynamic braking?

Answer 6

Forklift

Question 7

According to NEMA definitions, which of the following is a type of open motor?

Answer 7

Fan cooled

Question 8

A polyphase synchronous motor has three stator windings that are _____

Answer 8

120 degrees apart

Question 9

A typical constant-horsepower load is a _____

Answer 9

Lathe

Question 10

What is TRUE regarding the neutral plane in a single-loop DC motor?

Answer 10

No torque is produced in the neutral plane

Question 11

The most common service factor appearing on a motor nameplate is _____

Answer 11

1.15

Question 12

A capacitor-start motor is a single-phase motor that has a _____

Answer 12

High starting torque

Question 13

The continuity of motor leads can be checked using a(n) _____

Answer 13

Ohmmeter

Question 14

One method of varying the speed on a DC shunt motor is to adjust the voltage and current applied to the _____

Answer 14

Armature

Question 15

The synchronous speed at which a four-pole, 50Hz induction motor operates is _____

Answer 15

1,500rpm

Question 16

For a given number of poles, what determines the speed of an AC motor?

Answer 16

Frequency

Question 17

What is the D dimension of a medium-size motor with a frame number of 328T?

Answer 17

8

Question 18

A device that de-energizes the motor when the actual temperature rise equals the rated temperature rise must be installed on a _____

Answer 18

1,500 hp motor

Question 19

Which motor is the BEST choice for an application requiring adjustable speeds?

Answer 19

DC Shunt motor

Question 20

The terminals of a wye-connected motor can be identified using a battery and a(n) _____

Answer 20

Voltmeter

Question 21

DC injection braking is used on _____

Answer 21

The stationary windings of AC motors after the AC voltage is removed

Question 22

The NEC® requires motor disconnecting means to be _____

Answer 22

Within sight of the controller location

Question 23

Which motor is used to provide high starting torque and constant speed under load?

Answer 23

Series

Question 24

Which motor provides constant speed from no-load conditions to full-load conditions?

Answer 24

Synchronous

Question 25

A wound-rotor induction motor is used _____

Answer 25

For speed control and to limit starting current

Question 26

The value indicated in rpm on the nameplate is the _____

Answer 26

Rated full-load speed

Question 27

In a wye-connected motor, _____

Answer 27

Three coils are connected together and three are isolated

Question 28

The speed of a three-phase squirrel cage induction motor is controlled by the frequency of the applied voltage and the _____

Answer 28

Number of poles

Question 29

How is motor heating affected when operating a motor at reduced speeds?

Answer 29

The ability to dissipate heat is reduced at a reduced speed

Question 30

The approximate horsepower of a 15,000W DC motor is _____

Answer 30

20