Power System - I (3140914) MCQs

MCQs of Underground Cables

Showing 31 to 40 out of 112 Questions
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31.
Solid type cables are not considered suitable for operating voltage is exceeding 66 kV because
(a) Skin effect dominates on the conductor
(b) There is danger of breakdown of insulation because of formation of voids in the layer of dielectric
(c) There is a corona loss between conductor and sheath material
(d) Insulation may melt due to heating
Answer:

Option (b)

32.
In a three core extra high voltage cable, a metallic screen around each core insulation is provided to
(a) Facilitate heat dissipation
(b) Give mechanical strength
(c) Obtain radial electric stress
(d) Obtain longitudinal electric stress
Answer:

Option (c)

33.
The operating voltage and consequently the electric stress on the dielectric of solid type cable is increased from a low value, the dielectric power factor remains almost unchanged up to a certain value of the stress beyond which it increases very rapidly. This is due to increase in
(a) Resistivity of dielectric material
(b) Ionization of voids present in the dielectric
(c) Core to core capacitance of the cable
(d) Core to  earth capacitance of the cable
Answer:

Option (b)

34.
At Higher voltages, belted cables are more suitable than screened cables
(a) Yes
(b) No
(c) Cannot say anything
(d) Insufficient data
Answer:

Option (b)

35.
Cables generally used beyond 66 kV are
(a) Oil filled
(b) Belted
(c) H type
(d) SL type
Answer:

Option (a)

36.
Oil filled cables has the advantage of
(a) No ionization, oxidation and formation of voids
(b) Possibility of increased temperature range in service
(c) More maximum permissible stresses
(d) All of above
Answer:

Option (d)

37.
Oil filled cables has the drawback of
(a) No possibility of impregnation after sheathing
(b) Greater cost and complicated  installation of cables and maintenance
(c) High thermal resistance
(d) All of above
Answer:

Option (b)

38.
Cable used for 132 kV are
(a) High tension
(b) Super tension
(c) Extra super voltage
(d) Extra high tension
Answer:

Option (c)

39.
Oil filled cables has the advantage of
(a) Smaller overall size
(b) Most perfect impregnation
(c) Easy detection of world
(d) All of above
Answer:

Option (d)

40.
Cables used for 220 kV lines are invariably
(a) Compressed oil or compressed gas insulated
(b) Paper insulated
(c) Mica insulated
(d) None of above
Answer:

Option (a)

Showing 31 to 40 out of 112 Questions
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