Underground distribution lines installation of service connections - Electrical Engineering (MCQ) questions and answers

1)   Which type of cable is used for underground service connections?

a. Low tension 3 ¼ core cable
b. Low tension 3 ½ core cable
c. Low tension 2 ¼ core cable
d. Low tension 2 ½ core cable
Answer  Explanation 

ANSWER: Low tension 3 ½ core cable

Explanation:
No explanation is available for this question!


2)   What is the formula to calculate the number of poles required in LT line distribution?

a. Length / Span + 1
b. Length / Span + 10
c. Span / Length + 1
d. Span / Length + 10
Answer  Explanation 

ANSWER: Length / Span + 1

Explanation:
No explanation is available for this question!


3)   What should be the height of the ‘Roof Pole’?

a. Less than 5m
b. Less than 3m
c. More than 3m
d. More than 10m
Answer  Explanation 

ANSWER: Less than 3m

Explanation:
No explanation is available for this question!


4)   What is the multiplication factor used for the determination of maximum current carrying capacity of an 11 kV line?

a. 0.88
b. 0.95
c. 0.9
d. 0.8
Answer  Explanation 

ANSWER: 0.9

Explanation:
No explanation is available for this question!


5)   What should be the minimum clearance for laying power cables near communication lines?

a. 0.2 m horizontally and vertically
b. 0.6 m horizontally and vertically
c. 1 m horizontally and vertically
d. 1.5 m horizontally and vertically
Answer  Explanation 

ANSWER: 0.6 m horizontally and vertically

Explanation:
No explanation is available for this question!


6)   What should be the minimum depth of trench from the ground level for cables carrying a voltage between 3.3 kV and 11 kV?

a. 0.75 m plus radius of complete cable
b. 0.45 m plus radius of complete cable
c. 1.0 m plus radius of complete cable
d. All of these
Answer  Explanation 

ANSWER: 0.75 m plus radius of complete cable

Explanation:
No explanation is available for this question!


7)   Which type of stress is developed in a belted type cable construction used for voltage above 22 kV?

a. Radial stress
b. Tangential stress
c. Electrostatic stress
d. Both (A) and (B)
e. All of these
Answer  Explanation 

ANSWER: Both (A) and (B)

Explanation:
No explanation is available for this question!


8)   What is the dielectric constant of impregnated paper insulation?

a. 3.5
b. 2.5
c. 4.3
d. 3.8
Answer  Explanation 

ANSWER: 3.5

Explanation:
No explanation is available for this question!


9)   Which among these is the main requirement of the insulating materials?

i. Non inflammable
ii. High permittivity
iii. High dielectric strength


a. i and ii
b. i and iii
c. ii and iii
d. i, ii and iii
Answer  Explanation 

ANSWER: i and iii

Explanation:
No explanation is available for this question!


10)   Which type of cable does not require bedding?

a. Paper insulated lead covered cables
b. PVC cables
c. Both (A) and (B)
d. None of these
Answer  Explanation 

ANSWER: PVC cables

Explanation:
No explanation is available for this question!