A. to provide coupling between primary and secondary
B. to increase the magnitude of mutual flux
C. to decrease the magnitude of mag-netizing current
D. to provide all above features
Greater the secondary leakage flux____________?
A. less will be the secondary induced e.m.f.
B. less will be the primary induced e.m.f.
C. less will be the primary terminal voltage
D. none of the above
Spacers are provided between adjacent coils?
A. to provide free passage to the cooling oil
B. to insulate the coils from each other
C. both A. and (b)
D. none of the above
No-load current of a transformer has_____________?
A. has high magnitude and low power factor
B. has high magnitude and high power factor
C. has small magnitude and high power factor
D. has small magnitude and low power factor
Transformer breaths in when_______________?
A. load on it increases
B. load on it decreases
C. load remains constant
D. none of the above
The maximum efficiency of a distribution transformer is____________?
A. at no load
B. at 50% full load
C. at 80% full load
D. at full 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
Natural oil cooling is used for transformers up to a rating of____________?
A. 3000 kVA
B. 1000 kVA
C. 500 kVA
D. 250 kVA
In the transformer the function of a conservator is to_______________?
A. provide fresh air for cooling the transformer
B. supply cooling oil to transformer in time of need
C. protect the transformer from damage when oil expends due to heating
D. none of the above
In a transformer routine efficiency depends upon_____________?
A. supply frequency
B. load current
C. power factor of load
D. both B. and (c)