Deck 26: Wye-Delta Starting

Question 1

Dual voltage motors designed for wye-delta starting will supply all 12 T leads at the terminal connection box.

Answer 1

True

Question 2

Dual voltage motors not intended for wye-delta connection will have certain terminals tied internally.

Answer 2

True

Question 3

Open transition starting means that the motor is connected to the power line during the transition from wye to delta.

Answer 3

False

Question 4

What is the most critical part of connecting a wye-delta starter?

Question 5

Motors that are intended to operate on two voltages such as 240 or 480 volts contain two separate ____________________ of each phase.

Question 6

How is wye-delta starting accomplished?

Question 7

Closed transition starting does not disconnect the motor from the power line.

Question 8

Figure 26-9

What does the accompanying diagram show?

Question 9

What are the two requirements that must be met before wye-delta starting can be used?

Question 10

If the stator windings of a motor are connected in delta during the starting period, the starting current will be ____________________ times the value if the windings were connected in wye.

Question 11

Figure 26-1

What does the accompanying figure show?

Question 12

Wye-delta starting is sometimes called ____________________ starting.

Question 13

In a wye connection, the line current and phase current are not the same.

Question 14

Wye-delta starting is often used with large horsepower motors to reduce in-rush current during the starting period and reduce starting ____________________.

Question 15

If the stator windings are connected in ____________________, the voltage across each phase will be 480 volts because line voltage and phase voltage are the same in a(n) ____________________ connection.