Explore topic-wise MCQs in Transformers.

This section includes 15 Mcqs, each offering curated multiple-choice questions to sharpen your Transformers knowledge and support exam preparation. Choose a topic below to get started.

1.

Why transformers are paralleled?

A. Economical than replacing by one single large unit
B. Less maintaining cost
C. To handle more load
D. Economical factors, more load capacity, less maintenance
Answer» E.
Discussion
2.

Why transformers connected in parallel should have same voltage ratio?

A. To avoid full load circulating current
B. To avoid no-load circulating current
C. To avoid other losses
D. To avoid all type of currents
Answer» C. To avoid other losses
Discussion
3.

Y/Y and Y/D transformers can be paralleled.

A. True
B. False
Answer» C.
Discussion
4.

For three phase power transformers relative phase displacement should be ____________

A. 00
B. 300
C. 900
D. 1800
Answer» B. 300
Discussion
5.

Y/Y_AND_Y/D_TRANSFORMERS_CAN_BE_PARALLELED.?$

A. True
B. False
Answer» C.
Discussion
6.

Why transformers are paralleled?$

A. Economical than replacing by one single large unit
B. Less maintaining cost
C. To handle more load
D. Economical factors, more load capacity, less maintenance
Answer» E.
Discussion
7.

Why transformers connected in parallel should have same voltage ratio?$

A. To avoid full load circulating current
B. To avoid no-load circulating current
C. To avoid other losses
D. To avoid all type of currents
Answer» C. To avoid other losses
Discussion
8.

For three phase power transformers relative phase displacement should be ___________?

A. 00
B. 300
C. 900
D. 1800
Answer» B. 300
Discussion
9.

While connecting two transformers in parallel voltage around the local loop _________

A. positive
B. negative
C. equals zero
D. insufficient information
Answer» D. insufficient information
Discussion
10.

A delta/star transformer is connected in parallel to a star/delta transformer. The turn ratio former is x times latter, the x is _________

A. 3
B. 1/3
C. ‚àö3
D. 1/‚àö3
Answer» B. 1/3
Discussion
11.

If the percentage impedances of the two transformers working in parallel are different, then ______________________

A. transformers will be overheated
B. power factors of both the transformers will be same
C. parallel operation will be not possible
D. parallel operation will still be possible, but the power factors at which the two transformers operate will be different from the power factor of the common load
Answer» E.
Discussion
12.

What will happen if the transformers working in parallel are not connected with regard to polarity?

A. The power factor of the two trans-formers will be different from the power factor of common load
B. Incorrect polarity will result in dead short circuit
C. The transformers will not share load in proportion to their kVA ratings
D. Cannot be determined
Answer» C. The transformers will not share load in proportion to their kVA ratings
Discussion
13.

Transformers operating in parallel mode of operation will share the load depending upon their ___________

A. leakage reactance
B. per unit impedance
C. efficiencies
D. ratings
Answer» C. efficiencies
Discussion
14.

For the parallel operation of two single phase transformers it is necessary that they should have ________

A. same efficiency
B. same polarity
C. same kVA rating
D. same number of turns on the secondary side
Answer» C. same kVA rating
Discussion
15.

For two transformers connected in parallel, not having unequal percentage impedances, which statement is correct?

A. Short-circuiting of the secondaries
B. Power factor of one of the transformers is leading while that of the other lagging
C. Transformers having higher copper losses will have negligible core losses
D. Loading of the transformers not in proportion to their kVA ratings
Answer» E.
Discussion