Transmission and Distribution line MCQ Part-1

1. Transmission line connects__________.

a. Generating station to a switching station/ step down transformer station

 b. Step-down transformer station to service transformer banks

c. Distribution transformer to consumer premises

d. Service points to consumer premises

2. A 3-phase, 4-wire system is commonly used for__________.

a. Primary distribution

b. Secondary distribution

c. Primary transmission

d. Secondary transmission

3. The rated voltage of 3-phase power system is given as_________.

a. RMS phase voltage

b. Peak phase voltage

c. RMS line to line voltage

d. Peak line to line voltage

4. Which of the following is usually not the generating voltage ?

a. 6.6 kV

b. 9.9 kV

c. 11 kV

d. 13.2 kV

5. In a transmission system the feeder supplies power to________.

a. Transformer sub-station(step-up)

b. Service mains

c. Distributors

d. All of the above

6. Feeder is designed mainly from the point of view of__________.

a. Its current carrying capacity

b. Voltage drop in it

c. Operating voltage

d. Operating frequency

7.  Distributors are designed from the point of view of__________.

a. Its current carrying  capacity

b. Voltage drop in it

c. Operating voltage

d. Operating frequency

8. Transmission and distribution of electric power by underground system is superior to overhead system in respect of________. 

a. Appearance and public safety

b. Maintenance cost

c. Frequency of faults, power failure and accidents

d. All of the above

9. The main drawback(s) of underground system over overhead system is/are ___________.

a. Exposure to lightning 

b. Heavy initial cost

c. Exposure to atmospheric hazards such as smoke, ice, wind, etc.

d. Inductive interference between power and communication circuits

10. The main drawback(s) of overhead system over underground system is/are ___________.

a. Underground system is more flexible than overhead system 

b. Higher charging current

c. Surge problem

d. High initial cost

11. By increasing the transmission voltage double of its original value, the same power can be despatched keeping the line loss___________.

a. Equal to its original value

b. Half of original value

c. Double the original value

d. One-fourth of original value

12. If a fixed amount of power is  to be transmitted over certain length with fixed power loss, it can be said that volume of conductor is_________.

a. Inversely proportional to magnitude of the voltage and that of power factor of the load

b. Inversely proportional to square of the voltage and square of power factor of the load 

c. Proportional to square of voltage and that of power factor of the load

d. Proportional to magnitude of the village only

13. For  the same voltage drop, increasing the voltage of distributor n-times________.

a. Reduces the x-section of the conductor by n times 

b. Increases the x-section of the conductor by n times

c. Reduces the x-section of the conductor by n² times

d. Increases the x-section of the conductor by n² times

14. In a transmission system, the weight of copper used is proportional to__________.

a. E²

b. E

c. 1/E²

d. 1/E

15. The volume of copper required for an ac transmission line is inversely proportional to________.

a. Current

b. Voltage

c. pf

d. Both (b) and (c)

 

16. Improving pf_________.

a. Reduces  the current for given output

b. Increases losses in line

c. Increases the loss of station

17. For a given amount of power to be transmitted over a certain distance with fixed power loss, the volume of copper required is_________.

a. Directly proportional to voltage

b. Inversely proportional to voltage

c. Inversely proportional to the square of voltage and pf of the load

d. Directly proportional to the square of the voltage and pf of the load

18. For the same conductor length, same amount of power, same losses and same maximum voltage to earth, which system require minimum conductor area?

a. Single phase ac

b. 3 phase ac

c. 2 wire ac

d. 3 wire dc

19. Which of the following distribution system is preferred for good efficiency and high economy ?

a. Single phase, 2-wire system

b. 2-phase, 3-wire system

c. 3-phase, 3-wire system

d. 3-phase, 4-wire system   

 

20. The main reason for using high voltage for long distance power transmission is_________.

a. Reduction in transmission losses

b. Reduction in time of transmission

c. Increase in system reliability

d. None of the above

21. The maximum tension in a section of overhead line conductor between two supports of unequal height occurs at_______.

a. The higher support  

b. The lower point 

c. The midpoint of the conductor

d. None of the above

22. Stringing chart is useful_______.

a. For finding the sag in the conductor

b. In the design of tower 

c. In the design of insulator string

d. Finding the distance between towers

23. Hot template curves are plots of________.

a. Temperature and humidity 

b. Conductor sag and span lengths

c. Conductor weight and sag

d. None of the above

24. The effect of wind pressure is more predominant on________.

a. Insulators 

b. transmission lines

c. Supporting towers

d. None of the above

25. Galloping in transmission line conductors arises due to__________.

a. Asymmetrical layers of ice formation

b. Vortex phenomenon in light winds

c. Heavy weight of the line conductors

d. Adoption of the horizontal conductor configuration

Transmission and Distribution line MCQ Part-2

Transmission and Distribution line MCQ Part-3

Transmission and Distribution line MCQ Part-4

Transmission and Distribution line MCQ Part-5

Transmission and Distribution line MCQ Part-6

Transmission and Distribution line MCQ Part-7