Open circuit test on transformers is conducted to determine____________?

Related Mcqs:

1. Short circuit test on transformers is conducted to determine____________?

   A. hysteresis losses
   B. copper losses
   C. core losses
   D. eddy current losses

2. An open-circuit test on a transformer is conducted primarily to measure______________?

   A. insulation resistance
   B. copper loss
   C. core loss
   D. total loss
   E. efficiency
   F. none of the above

3. Sumpner’s test is conducted on transformers to determine_____________?

   A. temperature
   B. stray losses
   C. all-day efficiency
   D. none of the above

4. Two transformers are connected in parallel. These transformers do not have equal percentage impedance. This is likely to result in____________?

   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

5. During open circuit test of a transformer:

   A. primary is supplied rated voltage
   B. primary is supplied full-load current
   C. primary is supplied current at reduced voltage
   D. primary is supplied rated kVA

6. Which of the following is not a routine test on transformers ?

   A. Core insulation voltage test
   B. Impedance test
   C. Radio interference test
   D. Polarity test

7. Natural oil cooling is used for transformers up to a rating of____________?

   A. 3000 kVA
   B. 1000 kVA
   C. 500 kVA
   D. 250 kVA

8. Two transformers operating in parallel will share the load depending upon their____________?

   A. leakage reactance
   B. per unit impedance
   C. efficiencies
   D. ratings

9. For the parallel operation of 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.

10. Losses which occur in rotating electric machines and do not occur in transformers are___________?

    A. friction and windage losses
    B. magnetic losses
    C. hysteresis and eddy current losses
    D. copper losses