Chapter 14 QUIZ

GENERATORS

1. Name the two essential circuits of a generator. Briefly describe the parts of each.
2. When is the induced voltage of a coil zero?
3. When is the induced voltage of a rotating coil at its maximum value?

4. Is a.c. or d.c. produced inside a rotating coil?
5. How is d.c. obtained from a rotating coil ?
6. Adding coils to an armature does what to the. d.c. produced?
7. What connection is used between coils of an armature to produce a high and
    even voltage?
8. Why is a drum winding superior to a ring winding?
9. Distinguish between the stator and the rotor of an alternator.
10. Why are a-c machines designed opposite to d-c machines?

Chapter 14 ANSWERS

GENERATORS

1. Primary-pole pieces, yoke, windings and field. Secondary-armature consisting of coils
    and iron core.

2. When the coil is in the neutral plane.

3. When the coil sides are directly under the pole pieces.

4. Always a.c.
5. By rectifying the d.c. in a commutator.

6. More coils eliminate the peaks and valleys of current. Pulsations are reduced.
7. Series connections.
8. Less reluctance, cheaper, easier to repair, all coil sides cut flux.
9. The stator is the stationary part containing the armature windings. The rotor is the
    rotating part containing the field coils.
10. So that the high voltages obtained in a.c. will not be taken off on a shipping contact.

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