Testing and Commissioning of Electrical Equipments (2180901) MCQs

MCQs of Safety Management

Showing 71 to 80 out of 93 Questions
71.
The objective of earthing or grounding is
(a) to provide as low resistance possible to the ground
(b) to provide as high resistance possible to the ground
(c) to provide a flow of positive, negative and zero sequence currents
(d) All of these
Answer:

Option (a)

72.
Moisture content in the soil __ the earth soil resistance
(a) increase
(b) decrease
(c) does not affect
(d) none of the above
Answer:

Option (b)

73.
Factors on which soil resistance depends
(a) depth of the electrode
(b) moisture
(c) Nacl
(d) All of these
Answer:

Option (d)

74.
The ground resistance should be designed such that
(a) as low as possible
(b) as high as possible
(c) between -1 to -10 ohms
(d) between 5 - 10 ohms
Answer:

Option (a)

75.
For an EHV equipment for maintenance first it should be isolated and connected to ground because
(a) to provide low impedance
(b) to discharge the charging capacitance to ground
(c) protection for operating personnel
(d) to discharge the charging capacitance to ground and protection for operating personnel
Answer:

Option (d)

76.
The advantage of neutral earthing is
(a) Freedom from persistent arcing grounds
(b) Over voltages due to lightning can be discharged to earth
(c) Simplified design earth fault protection
(d) All of the these
Answer:

Option (d)

77.
In a star connected system without neutral grounding, zero sequence currents are
(a) Zero
(b) Phaser sum of phase currents
(c) Same as r.m.s. value of phase currents
(d) Same as peak value of phase currents
Answer:

Option (a)

78.
The advantage of neutral earthing
(a) Safety of personnel
(b) Reduction of earth fault current
(c) Elimination of arcing ground
(d) None of these
Answer:

Option (c)

79.
What do we connect with earth during earthing or grounding of the electrical system?
(a) connecting frame of electrical equipment (non-current carrying part)
(b) neutral point in a star-connected system
(c) one conductor of the secondary of a transformer
(d) all of these
Answer:

Option (d)

80.
Which of the following are the type of Grounding or earthing?
(a) Equipment grounding
(b) System grounding
(c) Equipment grounding and System grounding
(d) none of these
Answer:

Option (c)

Showing 71 to 80 out of 93 Questions