A. no-load
B. half-load
C. near full-load
D. 10% overload
Related Mcqs:
- Distribution transformers are generally designed for maximum efficiency around________________?
A. 90% load
B. zero load
C. 25% load
D. 50% load - Power transformers are designed to have maximum efficiency at___________?
A. nearly full load
B. 70% full load
C. 50% full load
D. no load - 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 - The permissible flux density in case of cold rolled grain oriented steel is around__________?
A. 1.7 Wb/m2
B. 2.7 Wb/m2
C. 3.7 Wb/m2
D. 4.7 Wb/m2 - The efficiency of two identical transformers under load conditions can be determined by_______________?
A. short-circuit test
B. back-to-back test
C. open circuit test
D. any of the above - N atural air coo ling is generally restricted for transformers up to__________?
A. 1.5 MVA
B. 5 MVA
C. 15 MVA
D. 50 MVA - The efficiencies of transformers compared with that of electric motors of the same power are____________?
A. about the same
B. much smaller
C. much higher
D. somewhat smaller
E. none of the above - Natural oil cooling is used for transformers up to a rating of____________?
A. 3000 kVA
B. 1000 kVA
C. 500 kVA
D. 250 kVA - Open circuit test on transformers is conducted to determine____________?
A. hysteresis losses
B. copper losses
C. core losses
D. eddy current losses - The secondary winding of which of the following transformers is always kept closed?
A. Step-up transformer
B. Step-down transformer
C. Potential transformer
D. Current transformer
