Deck 28: Direct Current Motors

Question 1

What are the three basic types of armature windings?

Answer 1

The three basic types are lap, wave, and frogleg.

Question 2

What are the three basic types of direct current motors?

Answer 2

The three basic types of direct current motors are series, shunt, and compound.

Question 3

When compound motors are installed, what should they be tested for?

Answer 3

When compound motors are installed, they should be tested to determine whether they are connected for cumulative or differential compounding.

Question 4

Series field windings are marked F1 and F2 in the terminal connection box.

Question 5

On what principal do series motors operate?

Question 6

Shunt field windings exhibit a much higher resistance than the series field windings.

Question 7

Shunt motors are often called ____________________ motors.

Question 8

Frogleg wound armatures are most often used in small machines.

Question 9

____________________ is the term used to indicate the relative strength of the series and shunt fields.

Question 10

Series type motors have one undesirable characteristic. What is it?

Question 11

Compound motors generally employ a field loss relay (FLR) that is intended to disconnect the motor from the power line in the event that shunt field current should be interrupted or drop below an acceptable level.

Question 12

The most common way of reversing the direction of rotation for a direct current motor is to reverse the direction of the current flow though the ____________________.

Question 13

The differential in speed from no load to full load is referred to as ____________________.

Question 14

Compound motors contain both a series and shunt field.

Question 15

When full line voltage is applied to both the armature and shunt field, the motor is said to operate at ____________________ speed.