Power System - I (3140914) MCQs

MCQs of Underground Cables

Showing 21 to 30 out of 112 Questions
1 2 3 4 5 6
21.
In paper insulated cables,  the conductor cross section is usually limited to
(a) 50 mm2
(b) 250 mm2
(c) 600 mm2
(d) 1200 mm2
Answer:

Option (c)

22.
The dielectric strength of impregnated paper is about
(a) 30 kV/mm
(b) 20 kV/mm
(c) 15 kV/mm
(d) 5 kV/mm
Answer:

Option (a)

23.
Paper used as an insulating material is usually treated with oily compound because it
(a) Is hygroscopic
(b) Gets electrostatically charged at high voltage
(c) Is porous
(d) All of above
Answer:

Option (b)

24.
Single core cables are usually not provided with armouring in order to
(a) Avoid excessive loss in the armour
(b) Make the cable more flexible
(c) Make the cable non hygroscopic
(d) None of above
Answer:

Option (a)

25.
Single core cables should have armour made of
(a) Magnetic material
(b) Nonmagnetic and non-conducting material
(c) Nonmagnetic but conducting material
(d) Conducting material
Answer:

Option (c)

26.
Multi core cables generally use
(a) Oval shaped conductors
(b) Sector shaped conductor
(c) Square conductors
(d) Either (a) or (b)
Answer:

Option (d)

27.
In a 3 phase, 4 wire cable, the cross sectional area of neutral conductor is
(a) Half of the area of phase conductor
(b) Equal to the area of phase conductor
(c) Double the area of phase conductor
(d) 1.5 times the area of phase conductor
Answer:

Option (b)

28.
Belted type construction is not suitable for cables used for voltages exceeding 22 kV because of
(a) Development of both radial and tangential stresses
(b) Formation of vacuous and voids on loading and unloading owning to owing to  non-homogeneity of dielectric in belted construction
(c) Local heating caused by power loss at centre filling owning to leakage current produced by tangential stresses along the impregnated paper insulation resulting in breakdown it anytime
(d) All of above
Answer:

Option (d)

29.
SL type cables, over H type cables, has the advantage of
(a) Possibility of bending of cables owning to no overall lead sheath
(b) Less tendency for oil drainage on hilly route owning to elimination of filler space containing compounds
(c) Easy manufacturing
(d) Both (a) and (b)
Answer:

Option (d)

30.
Screened type cables, over belted cables has advantage of
(a) Reduced possibility of core to core faults
(b) Uniform radial dielectric stresses in all section of the dielectric
(c) No possibility of formation of voids within the dielectric
(d) All of above
Answer:

Option (d)

Showing 21 to 30 out of 112 Questions
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