MCQs of Underground Cables (Power System - I - 3140914)

Showing 61 to 70 out of 112 Questions

61.

Capacitance grading of cables means

(a)	Use of dielectrics in different concentration
(b)	Introduction of capacitance at various length of cable to counter the effect of inductance
(c)	Use of dielectrics of different permittivity
(d)	Grading according to capacitance per km length of the cable

62.

Grading of cables

(a)	Reduces insulation cost and increases current rating
(b)	Reduces installation cost but decreases current rating
(c)	Increases both
(d)	None of above

63.

Inter sheath in cables are used to

(a)	Provide proper stress distribution
(b)	Minimize the stress
(c)	Use inferior insulation
(d)	Provide protection against current and voltage surges

64.

The desired overall diameter of conductor without increasing its cross sectional area can be achieved by

(a)	Using aluminum core instead of copper
(b)	Stranding the copper conductors around hemp center
(c)	Standing the copper conductors over a lead tube
(d)	Any of above

65.

In a 3 core cable, capacitance between two conductors with sheath earthed is 3 μF. The capacitance per phase will be

66.

Aluminum conductor cable can be joined by

67.

The methods used for joining of copper conductor cables and aluminum conductor cables are

68.

The methods used for laying of underground cables are

69.

Direct laying method of laying underground cable has drawback of

(a)	High maintenance cost
(b)	Localization of fault difficulty
(c)	Possibility of damage of cable sheath owning to undergoing chemical changes due to impurities present in the soil
(d)	All of above

70.

Draw in system of laying underground cable has drawback of

(a)	Higher cost
(b)	Reduced current carrying capacity of the cable
(c)	Requirements of much deeper and wider Trench
(d)	All of above

Showing 61 to 70 out of 112 Questions