D.C. windings are____________?

A. Sometimes 2-layer type
B. Never 2-layer type
C. Always 2-layer type
D. None of the above

The high voltage winding is usually which of the following type ?

A. Cylindrical winding with circular conductors
B. Cross-over winding with either circular or small rectangular conductors
C. Continuous disc type winding with rectangular conductors
D. All of the above types

The flash point of transformer oil should be higher than_______________?

A. 40°c
B. 60°c
C. 80°c
D. 104°c

The usual values of maximum flux densities for distribution transformers using hot rolled silicon steel are______________?

A. 0.5 to 0.8 wb/m2
B. 0.8 to 1.0 wb/m2
C. 1.1 to 1.35 wb/m2
D. 1.4 to 1.8 wb/m2

For large power transformers, self oil cooled type or air blast type which of the following values of current density may be used?

A. 1.0 to 1.2 a/mm2
B. 1.5 to 2.0 a/mm2
C. 2.2 to 3.2 a/mm2
D. 3.2 to 4.2 a/mm2

A practical formula for determining the thickness of insulation between low voltage and high voltage windings is__________________?

A. 1 + 0.2 kvmm
B. 2 + 0.5 kvmm
C. 4 + 0.7 kv mm
D. 5 + 0.9 kv mm

The surge phenomenon is particularly important in case of_______________?

A. Low voltage transformers
B. Medium voltage transformers
C. High voltage transformers
D. Any of the above

The insulation between windings and grounded core and the insulation between the windings of the same phase is called__________________?

A. Minor insulation
B. Major insulation
C. Either of the above
D. None of the above

____________ is the common method of applying brushes to the commntator?

A. Radial
B. Trailing
C. Reaction
D. All of the above

___________ brushes are fragile and cause excessive wear of commutator?

A. Natural graphite
B. Hard carbon
C. Electro graphitic
D. Metal graphite