Deck 3: Self-Excited Shunt Generator

Question 1

The motorizing test can be used for restoring residual flux if the generator armature is mechanically engaged to the prime mover and cannot rotate freely.

Answer 1

False

Question 2

The terms voltage regulation and voltage control have the same meaning.

Answer 2

False

Question 3

To maintain the original ____________________ when renewing the residual magnetism, the electrical polarities of the output leads and the exciting battery mush be matched.

Answer 3

brush polarity

Question 4

How are field rheostats used in shunt generators?

Question 5

Unlike the separately excited generator, there is no current in the field circuit when the ____________________ is motionless.

Question 6

Voltage ____________________ refers to automatic changes in the terminal voltage due to reactions within the generator as the load current changes.

Question 7

Briefly describe what happens to the voltage of a self-excited shunt generator after the poles are established.

Question 8

Any generator has critical field resistance.

Question 9

Explain how to check for proper contact pressure using a simple resistance test.

Question 10

If the direction of armature rotation is reversed at start-up, the brush polarity is also reversed.

Question 11

____________________ are used to control the voltage output of shunt generators.

Question 12

Contact resistance at the brushes is another reason for the failure of the generator to develop its ____________________.

Question 13

There is only one method that can be used to renew the residual magnetism.

Question 14

What formula is used to determine the percent of voltage regulation?

Question 15

Why are voltage regulators used in aircraft and automobiles?