MCQs of Transients in Power Systems (Power System - II - 3150911)

Power System - II (3150911) MCQs

MCQs of Transients in Power Systems

Showing 61 to 70 out of 106 Questions

61.

Which of the following is the protective device against lightning over voltage?

(a)	Road gap
(b)	Surge absorber
(c)	Horn gap
(d)	All of above

62.

Overhead ground wires are used to protect a transmission line against

(a)	Line to ground faults
(b)	Arcing earths
(c)	Voltage surges due to direct lightning stroke
(d)	High Voltage oscillations due to switching

63.

In thyrite lightning arrester the resistance

(a)	Varies linearly with the applied voltage
(b)	Increases with the applied voltage
(c)	Decreases with the applied voltage
(d)	Is high at low current and low at high current

64.

An ideal surge diverter should have the characteristics

(a)	Its power frequency breakdown or spark over must be above normal or abnormal fundamental frequency
(b)	When the value of voltage transient to peak exceeds the spark over value of the surge diverter, a conducting path to earth must be provided
(c)	After occurrence of breakdown, it must carry the resulting discharge current without any damage to it
(d)	All of above

65.

Lightning arrester provides

(a)	Low impedance path
(b)	High impedance path
(c)	Low resistance path
(d)	High resistance path between line and earth during operation

66.

Location of lightning arrester is near to

(a)	Generator
(b)	Transformer
(c)	Bus bar
(d)	Circuit breaker

67.

Surge absorbers are used for protection against

(a)	High voltage low frequency oscillations
(b)	High Voltage high frequency oscillations
(c)	Low voltage high frequency oscillations
(d)	Low voltage low frequency oscillations

68.

Surge modifiers are employed to

(a)	Reduce the stiffness of waveform
(b)	Reduce the current of wave front
(c)	Reduce the voltage of wave front
(d)	Modify the shape of wave front

69.

Which of the following are the important limitations of rod gap surge arrester?
1. They are not capable of sealing off power frequency follow up current
2. After a discharge, roads are destroyed completely
3. Performance is affected by climatic condition

(a)	1, 2 and 3 are correct
(b)	1 and 2 are correct
(c)	2 and 3 are correct
(d)	1and 3 are correct

70.

Thyrite type lightning arrester

(a)	Blocks the surge voltage appearing in a line
(b)	Absorbs the surge voltage appearing in a line
(c)	Offers a low resistance path to the surge appearing in a line
(d)	Returns the surge back to the source

Showing 61 to 70 out of 106 Questions