Deck 20: Wye-Delta Starting, Part Winding Starters

Question 1

Part winding starting is another method of increasing the starting current of squirrel-cage induction motors.

Answer 1

False

Question 2

The thermal capacity of the stator windings greatly expands the length of starting time for a part winding motor.

Answer 2

False

Question 3

Part winding starting reduces the normal locked rotor current to approximately ____ percent of the value if both windings are connected during starting and the torque is reduced to approximately 50%.

A) 40
B) 50
C) 66
D) 83

Answer 3

66

Question 4

One advantage of part winding starters is that they provide ____ starting.

A) inductive
B) dual-voltage
C) closed transition
D) open transition

Question 5

As a general rule, a time delay of two to three seconds is common before the second winding is connected in ____________________ with the first.

Question 6

What are some typical part winding applications?

Question 7

Wye-delta starting is accomplished by connecting the motor stator windings in wye, or star, during the starting period and then reconnecting them in delta during the run period.

Question 8

If the motor is to be operated on the higher voltage, the stator leads will be connected in ____________________.

Question 9

What is open transition starting and how does it differ from closed transition starting?