Helical coils can be used on___________?
A. low voltage side of high kVA transformers
B. high frequency transformers
C. high voltage side of small capacity transformers
D. high voltage side of high kVA rating transformers
Part of the transformer which is most subject to damage from overheating is_____________?
A. iron core
B. copper winding
C. winding insulation
D. frame or case
E. transformer tank
The efficiency of a transformer will be maximum when_____________?
A. copper losses = hysteresis losses
B. hysteresis losses = eddy current losses
C. eddy current losses = copper losses
D. copper losses = iron losses
If the supply frequency to the transformer is increased,”the iron loss will__________?
A. not change
B. decrease
C. increase
D. any of the above
The magnetising current of a transformer is usually small because it has___________?
A. small air gap
B. large leakage flux
C. laminated silicon steel core
D. fewer rotating parts
A no-load test is performed on a transformer to determine_______________?
A. core loss
B. copper loss
C. efficiency
D. magnetising current
E. magnetising current and loss
Power transformers are generally designed to have maximum efficiency around__________?
A. no-load
B. half-load
C. near full-load
D. 10% overload