Question 1

For the primary side of the delta bank, coil current equals ____________________ A.

Accepted Answer

8.33

Question 2

The delta-wye transformer bank is well adapted for stepping up voltages.

Accepted Answer

The delta-wye transformer bank is commonly used for stepping up voltages. The delta connection on the primary side allows for the handling of high currents at a lower voltage, while the wye connection on the secondary side provides a higher voltage with lower current capacity. This configuration is commonly used in power distribution systems to raise the voltage level for efficient transmission over long distances.

Question 3

Another name for the open-wye-open-delta connection is the ____________________.

Accepted Answer

wye-delta with one transformer missing
wye-delta with 1 transformer missing

Question 4

In an open-wye-open-delta connection, the primary winding is connected to two of the three phase conductors, and the common point is connected to the ____________________.

Accepted Answer

The answer of In an open-wye-open-delta connection, the primary winding...

Question 5

What are the advantages of the three-phase transformer?

Accepted Answer

The answer of What are the advantages of the three-phase...

Question 6

What is the one disadvantage to the use of a three-phase transformer?

Accepted Answer

The answer of What is the one disadvantage to the...

Question 7

The open-wye-open-delta transformer connection is sometimes used to deliver small amounts of three-phase power to a secondary load and deliver larger amounts of single-phase power to the secondary load.

Accepted Answer

The open-wye-open-delta transformer connection provides a way to deliver both three-phase and single-phase power to a secondary load. It is commonly used in situations where the amount of three-phase power required is small compared to the amount of single-phase power needed.

Question 8

____________________ leads are brought out when any wye-connected windings are used in a three-phase transformer.

Accepted Answer

The answer of ____________________ leads are brought out when any...

Question 9

How are the secondary coils connected in an open-wye-open-delta transformer connection?

Accepted Answer

The answer of How are the secondary coils connected in...

Question 10

What is the difference between "transformer ratio" and "transformation ratio"?

Accepted Answer

The answer of What is the difference between "transformer ratio"...

Question 11

What two types of service are available as a result of the three-phase, four-wire secondary system?

Accepted Answer

The answer of What two types of service are available...

Question 12

Three-phase transformers may only be connected in delta-delta and wye-wye.

Accepted Answer

Three-phase transformers can also be connected in delta-wye and wye-delta configurations.

Question 13

A transformer connected in ____________________ is the type most often used to step down relatively high transmission line voltages (60,900 volts or more) at the consumer's location.

Accepted Answer

The answer of A transformer connected in ____________________ is the...

Question 14

The three single-phase transformers used in a delta-wye connection have different kVA capacities.

Accepted Answer

In a delta-wye transformer connection, the three single-phase transformers typically have the same kVA capacities to ensure balanced load distribution and proper operation of the system.

Question 15

For the primary side of the delta bank, the line voltage and the coil voltage are the same.

Accepted Answer

In a delta connection, the line voltage and the coil voltage are the same on the primary side.

Quiz 19: Alternate Wye and Delta Connections of Transformers