Explore topic-wise MCQs in Transformers.

This section includes 18 Mcqs, each offering curated multiple-choice questions to sharpen your Transformers knowledge and support exam preparation. Choose a topic below to get started.

1.

x/√3:1 ratio is obtained in ______________

A. Star/delta
B. Delta/star
C. Delta/delta
D. Star/star
Answer» C. Delta/delta
2.

What is the ratio of transformation of star/delta connection?

A. Phase transformation x:1, line transformation x:1
B. Phase transformation x:1, line transformation √3x:1
C. Phase transformation x:1, line transformation 3x:1
D. Can’t determine with information available
Answer» B. Phase transformation x:1, line transformation √3x:1
3.

Star/delta connection is also called as ____________

A. 300-connection
B. 00-connection
C. -300-connection
D. 300/-300-connection
Answer» E.
4.

Open delta connection has VA rating of _______________

A. √3 times delta/delta VA rating
B. 1/√3 times delta/delta VA rating
C. 3 times delta/delta VA rating
D. 1/3 times delta/delta VA rating
Answer» C. 3 times delta/delta VA rating
5.

What is the ratio of transformation of delta/delta connection?

A. Phase transformation x:1, line transformation x:1
B. Phase transformation x:1, line transformation 2x:1
C. Phase transformation x:1, line transformation x/3:1
D. Can’t determine
Answer» B. Phase transformation x:1, line transformation 2x:1
6.

In a three-phase star – delta transformer, what is the angle difference between primary and secondary phase voltages?

A. Delta side leads by 300
B. Delta side lags by 300
C. Star side leads by 300
D. Star side lags by 300
Answer» B. Delta side lags by 300
7.

OPEN_DELTA_CONNECTION_HAS_VA_RATING_OF________________?$

A. ‚àö3 times delta/delta VA rating
B. 1/‚àö3 times delta/delta VA rating
C. 3 times delta/delta VA rating
D. 1/3 times delta/delta VA rating
Answer» C. 3 times delta/delta VA rating
8.

What is the ratio of transformation of star/delta connection?$

A. Phase transformation x:1, line transformation x:1
B. Phase transformation x:1, line transformation ‚àö3x:1
C. Phase transformation x:1, line transformation 3x:1
D. Can’t determine with information available
Answer» B. Phase transformation x:1, line transformation ‚Äö√Ñ√∂‚àö‚Ć‚àö‚àÇ3x:1
9.

Star/delta_connection_is_also_called_as_____________$

A. 300-connection
B. 00-connection
C. -300-connection
D. 300/-300-connection
Answer» E.
10.

Which both connections have the same line transformation ratios?

A. Star/star and delta/delta
B. Star/delta and delta/star
C. Star/zig-zag star and delta/zig-zag star
D. Star/star, delta/delta and star/delta, delta/star
Answer» E.
11.

x/‚àö3:1 ratio is obtained in ______________$

A. Star/delta
B. Delta/star
C. Delta/delta
D. Star/star
Answer» C. Delta/delta
12.

Delta/delta connection is also called as ____________

A. 00-connection
B. 900-connection
C. 1800-connection
D. 00/1800-connection
Answer» E.
13.

What is the ratio of transformation of star/star connection?

A. Phase transformation x:1, line transformation x:1
B. Phase transformation x:1, line transformation 2x:1
C. Phase transformation x:1, line transformation x/3:1
D. Can’t say
Answer» B. Phase transformation x:1, line transformation 2x:1
14.

Which can be also called as 00 /1800 connection?

A. Star/star
B. Direct star
C. Delta/star
D. Star/delta
Answer» B. Direct star
15.

In a three-phase star – delta transformer, what is the angle difference between primary and secondary phase voltages?$

A. Delta side leads by 300
B. Delta side lags by 300
C. Star side leads by 300
D. Star side lags by 300
Answer» B. Delta side lags by 300
16.

Scott connections are used in _______________

A. three-phase to single phase transformation
B. three-phase to two-phase transformation
C. single phase to three-phase transformation
D. all phase transformations
Answer» C. single phase to three-phase transformation
17.

When does delta/star transformer work satisfactorily?

A. Load is balanced only
B. Load is unbalanced only
C. On balanced as well as unbalanced loads
D. Independent of load type
Answer» D. Independent of load type
18.

When does star/star transformers work satisfactorily?

A. Load is unbalanced only
B. Load is balanced only
C. On balanced as well as unbalanced loads
D. Independent of load type
Answer» C. On balanced as well as unbalanced loads