Power System Planning and Design (2180903) MCQs

MCQs of Insulation co-ordination

Showing 11 to 20 out of 43 Questions
11.
In a thyrite lightning arrester the resistance
(a) Varies linearly with the applied voltage
(b) Increases with the applied voltage
(c) Decreases linearly with the applied voltage
(d) Is high at low current and low at high current
Answer:

Option (d)

12.
A 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
Answer:

Option (a)

13.
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
Answer:

Option (c)

14.
Surge modifiers are employed for
(a) Reducing the steepness of wave-front
(b) Reducing the current of wave-front
(c) Reducing the voltage of wave-front
(d) Modify the shape of the wave-front
Answer:

Option (a)

15.
A 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
Answer:

Option (c)

16.
A lightning arrester connected between the line and earth in a power system
(a) Protects the terminal equipment against travelling surges
(b) Protects the terminal equipment against direct lightning stroke
(c) Suppresses high frequency oscillations in the line
(d) Reflects back the travelling waves approaching it
Answer:

Option (a)

17.
Which of the following is a non-linear diverter?
(a) Expulsion type arrester
(b) Valve type arrester
(c) Electrolytic type arrester
(d) Rod gap arrester
Answer:

Option (b)

18.
A valve type lightning arrestor in a substation should be placed
(a) Close to the circuit breaker
(b) Close to the transformer
(c) Away from the transformer
(d) None of above
Answer:

Option (b)

19.
Surge absorber ____________ the energy of travelling waves
(a) Absorbs
(b) Reflects
(c) Diverts
(d) Partly absorbs and partly diverts
Answer:

Option (d)

20.
Coupling factor of a ground wire can be increased by
(a) Reducing the footing impedance
(b) Increasing the ground wire size
(c) Using cantilever rods on the crossing along-with the areas of ground wire
(d) All of above
Answer:

Option (d)

Showing 11 to 20 out of 43 Questions