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Flashcards in Unit 21 Deck (9)
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1

The rotor of an ac generator contains the ________ field, which develops the magnetic flux lines

Electromagnetic

2

The current used for the field winding is called the ____ ____

Excitation current

3

Direct-current generators require a _____ field to induce voltage in the rotating armature to create current flow

Magnetic

4

When the generator supplies the excitation current it is called what?

Self-excited generator

5

If a separate dc power source is used to supply the excitation field, the generator is called what?

Separately excited generator

6

There are six leads from the windings of a three-phase generator which can be connected in ____ for delta connections or in _____ for wye connections

Series ; Parallel

7

In an ac generator the magnetic lines of force from the rotor electromagnet are made to cut through the stationary conductor coils. The relative motion between the lines of force and the conductor coils produces an ______ force in the conductors

Electromotive

8

Three-phase ac generators have three equally spaced windings, all _____ degrees out-of-phase with each other

120

9

If the magnetic field is created by an electromagnet, the electromagnetic field is called what?

Field winding