A transformer can have regulation closer to zero___________?
(A) on full-load
(B) on overload
(C) on leading power factor
(D) on zero power factor
In a transformer the resistance between its primary and secondary should be_____________?
(A) zero
(B) 10 Q
(C) 1000 Q
(D) infinity
The secondary of a current transformer is always short-circuited under operating conditions because it____________________?
(A) avoids core saturation and high voltage induction
(B) is safe to human beings
(C) protects the primary circuit
(D) none of the above
A shell-type transformer has_________?
(A) high eddy current losses
(B) reduced magnetic leakage
(C) negligibly hysteresis losses
(D) none 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 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
The function of breather in a transformer is___________?
(A) to provide oxygen inside the tank
(B) to cool the coils during reduced load
(C) to cool the transformer oil
(D) to arrest flow of moisture when outside air enters the transformer
For given applied voltage, with the increase in frequency of the applied voltage?
(A) eddy current loss will decrease
(B) eddy current loss will increase
(C) eddy current loss will remain unchanged
(D) none of the above
In a power or distribution transformer about 10 per cent end turns are heavily insulated__________?
(A) to withstand the high voltage drop due to line surge produced by the shunting capacitance of the end turns
(B) to absorb the line surge voltage and save the winding of transformer from damage
(C) to reflect the line surge and save the winding of a transformer from damage
(D) none of the above
Reduction in core losses and increase in permeability are obtained with transformer employing__________?
(A) core built-up of laminations of cold rolled grain oriented steel
(B) core built-up of laminations of hot rolled sheet
(C) either of the above
(D) none of the above