Power Transformer MCQs Part 01

  1. Which of the following minimised by iaminating the core of a transformer
    a. Hysteresis loss
    b. Eddy current loss
    c. Heat loss
    d. All of the above

2. The function of breather in a transformer is
a. To provide oxygen to the cooling oil
b. To provide cooling air
c. To arrest flow of moisture when outside air enters the transformer
d. To filter the transformer oil

3. Iron loss in a transformer occur is
a. core
b. winding
c. insulating oil
d. main body

4. Under no load conditions. which of the following loss is negligible
a. Hysteresis loss
b. Eddy current loss
c. Copper loss
d. All losses have same magnitude

5. Open circuit test of a transformer gives
a. hysteresis loss
b. eddy current loss
c. sum of hysteresis and eddy current loss
d. copper loss

6. Copper loss in a transformer occurs in
a. core
b. winding
c. main body
d. bushings

7. Which test on a transformer provides information about regulation, efficiency and heading under load conditions?
a. Open circuit test
b. Back to back test
c. Hopkinson test
d. Short circuit test

8. For a transformer the condition for maximum efficiency is
a. Hysteresis loss = eddy current loss
b. core loss = hysteresis loss
c. copper loss = iron loss
d. total loss = 2/3 x copper loss

9. Eddy current losses in a transformer core can be reduced by
a. reducing the thickness of laminations
b. increasing the thickness of laminations
c. increasing the airgap in the magnetic circuit
d. reducing the airgap in the magnetic circuit

10. In a transformer the magnetic coupling between the primary and secondary circuit can be increased by
a.increasing the number of turns
b. using soft material for windings
c. using magnetic core of low reluctance
d. using transformer oil of better quality