Transformers

Question 1

Induction describes what?

Answer 1

The electrical operation of a transformer

Question 2

2 types of bushings

Answer 2

Primary and secondary

Question 3

Two types of secondary bushings

Answer 3

3-bushing
4-bushing

Question 4

Polarity describes what?

Answer 4

2 different methods of winding the coils around the core to induce voltage

Question 5

Can polarity be changed after the transformer is built?

Answer 5

No

Question 6

Additive core winding is what?

Answer 6

Induces secondary voltage in an opposite direction than primary voltage

Question 7

What is subtractive winding?

Answer 7

Induces secondary voltage in the same direction as primary voltage

Question 8

Direction of feed is what?

Answer 8

Describes which primary bushing is connected to the primary phase feeding the transformer

Question 9

Right hand feed

Answer 9

Transformer is fed from primary phase to right side bushing when looking at it from pole side

Question 10

Left hand feed

Answer 10

Transformer is fed from primary phase to left side bushing when looking at it from pole side

Question 11

Induced voltage is directly proportional to the what?

Answer 11

The ratio of windings in primary coil to windings in secondary coil

Question 12

T or F? Different primary distribution voltages 4kV, 12kV, and 34kV can use the same winding ratio

Answer 12

False

Question 13

What’s a tap changer?

Answer 13

Allows a transformer to work on more than one voltage

Question 14

What should the nameplate be checked for?

Answer 14

Rated primary and secondary voltages

Polarity

Primary tap settings

Correct size kVA

Question 15

Y transformers work with what voltages?

Answer 15

Phase to neutral

Question 16

∆ transformers work with what voltages?

Answer 16

Phase to phase