Three Phase Transformers MCQ

Test your knowledge with important Three Phase Transformers MCQ and their applications. These MCQs are beneficial for competitive exams too. Explore 30 + more Three Phase Transformers MCQs at Bissoy

• Shape of emf generated by delta connected transformer is not always sinusoidal.
  ক

  True

  খ

  False
• A recording of the output of the emf induced for star and delta are recorded. Then shape of the emf induced in Y-connected 3-phase transformer is non sinusoidal in nature due to ___________
  ক

  3rd harmonic component of currents is absent

  খ

  3rd harmonic component of currents is present

  গ

  negative sequence component of current is present

  ঘ

  none of the mentioned
• While using three phase transformers, it is taken care about the third harmonics current in the system. This is present when transformer set is delta on either side.
  ক

  True

  খ

  False
• A 400 V, 10 KVA transformer at 50 Hz, is operated at the frequency of 40 Hz, then the humming ___________
  ক

  increases

  খ

  decreases

  গ

  remains same

  ঘ

  increases to very high
• When we magnetize the ferromagnetic core of the transformer, core length_______ and it ______ when demagnetized.
  ক

  decreases, increases

  খ

  decreases, decreases

  গ

  increases,increases

  ঘ

  none of the mentioned
• If para magnetic core is used in the place of the ferromagnetic core of the transformer, then magnetostriction will ___________
  ক

  be vanished

  খ

  reduce

  গ

  increase

  ঘ

  not be affected
• Below is the circuit diagram for delta-delta transformer have a transformation ratio ‘k’. The current flowing in the windings of phase r-y in the below diagrams is?
  ক

  k*I/1.73

  খ

  I/k*1.73

  গ

  1.73*k*I

  ঘ

  3*k*I
• If one of the transformers is removed from the bank of only delta-delta, then it behaves with 58% power delivery.
  ক

  True

  খ

  False
• Open delta transformers can be obtained from ___________
  ক

  delta-delta

  খ

  star-delta

  গ

  delta-star

  ঘ

  any of the mentioned
• The delta-delta connections are used in applications of ___________
  ক

  large l.v. transformers

  খ

  small h.v. transformers

  গ

  large h.v. transformers

  ঘ

  small l.v. transformers
• The voltage across the terminal ‘r’ and ‘y’ is?
  ক

  1.73*V

  খ

  V/1.73

  গ

  V

  ঘ

  3*V
• For the given circuit below, the voltage across the terminal ‘a’ and ‘b’ is?
  ক

  1.73*V

  খ

  V/1.73

  গ

  V

  ঘ

  3*V
• The transformer which is more feasible to use in the distribution ends should be ___________
  ক

  star-delta

  খ

  delta-star

  গ

  scott

  ঘ

  delta-delta
• Three units of single phase transformers and one single three-phase transformer rating ___________
  ক

  will be same for one rating

  খ

  can never be made same

  গ

  may be same

  ঘ

  none of the mentioned
• A V-V connected transformer can be connected in parallel to delta-delta connected transformer but not to ___________
  ক

  delta-star

  খ

  star-delta

  গ

  star-V

  ঘ

  all of the mentioned