Question 1 of 25

1. Why the disc pin insulators outer surface is made by glazing and bent the sides inward?

To withstand high voltage

Disables continuous water flow in rainy season

To offer high mechanical strength

Not to attract birds to sit on it

Question 1 of 25

Question 2 of 25

2. What is the purpose of cross-arm in O.H lines?

Protect from short between conductors

Reduce the sag of the lines between poles

Holding the insulators where the conductors are fastened

Provide more support to the O.H pole

Question 2 of 25

Question 3 of 25

3. Which is the permissible load for lighting subcircuit in domestic wiring as per IE rules?

3000 W

2400 W

800 W

1200 W

Question 3 of 25

Question 4 of 25

4. Which electric lines connect the substation to distributors in distribution system?

Distributors

Feeders

Service lines

Service mains

Question 4 of 25

Question 5 of 25

5. What is the name of the insulator?

Suspension insulator

Shackle insulator

Stay insulator

Single shed pin insulator

Question 5 of 25

Question 6 of 25

6. What is the insulation resistance between any two conductors in a medium voltage domestic installation as per IE rules?

More than one Mega ohm

Infinity

More than two Mega ohms

More than three Mega ohms

Question 6 of 25

Question 7 of 25

7. How the sparking on the aluminium cored conductors binding joints can be prevented?

Providing guard wires below the conductors

Keeping binding turns very close

Providing more than one binding

Making binding turns very tight

Question 7 of 25

Question 8 of 25

8. What is the advantage of AC power transmission?

Low voltage drop in transmission lines

Corona loss negligible

Voltages can be stepped up and stepped down easily

Stress on transmission lines is minimum

Question 8 of 25

Question 9 of 25

9. What will happen to the skin effect on the O.H conductors, if the conductor diameter is small (<1cm)?

Decreases half of the value

No effect, remain same

Becomes negligible

Increases to maximum

Question 9 of 25

Question 10 of 25

10. Why steel is reinforced in ACSR conductors used for over head lines?

To minimize the line sag

To increase the current carrying capacity

To increase the tensile strength

To reduce the line voltage drop

Question 10 of 25

Question 11 of 25

11. What is ACSR stands for?

Aluminium Conductor Steel Reinforced

Aluminium Covered Steel Reinforced

Aluminium Core Steel Reinforced

All Conductors Steel Reinforced

Question 11 of 25

Question 12 of 25

12. Which type of line insulator is used for terminating on corner post?

Shackle insulator

Strain insulator

Suspension insulator

Pin insulator

Question 12 of 25

Question 13 of 25

13. Which type of line insulator is used at the dead ends of the H.T overhead lines?

Stay insulator

Disc insulator

Post insulator

Pin insulator

Question 13 of 25

Question 14 of 25

14. What is the voltage ratio in A.C distribution line adopted for domestic consumers?

415 V/240 V

240 V/110 V

11 KV/415 V

415 V/110 V

Question 14 of 25

Question 15 of 25

15. What is the type of over head line joint?

Straight joint through connectors

Straight sleeve joint

Twisted joint

Compression joint for ACSR

Question 15 of 25

Question 16 of 25

16. What is the name of line insulator?

Suspension type insulator

Disc type insulator

Shackle type insulator

Pin type insulator

Question 16 of 25

Question 17 of 25

17. What is the reason for the conductor cross-sectional area can fully utilised on transmission of DC as compared to AC?

No corona loss

No heat loss

No skin effect

No power loss

Question 17 of 25

Question 18 of 25

18. Which type of A.C transmission is universally adopted?

Single phase two wire

Three phase three wire

Two phase three wire

Two phase four wire

Question 18 of 25

Question 19 of 25

19. What is the main purpose of crossarm used in electric poles?

Holding the insulators on overhead line

Supporting the line conductors

Reduces conductor sag between supports

Avoids short circuit between conductors

Question 19 of 25

Question 20 of 25

20. What is the reason of keeping binding wire gap too close and very tight in pin insulator?

Avoid sparking

Avoid oxide formation

Avoid corrosion

Avoid atmospheric pressure

Question 20 of 25

Question 21 of 25

21. What will happen to the string arrangement of disc insulators, if one of the disc insulator gets damaged?

Whole string become useless

Damaged insulator and the adjacent insulator will not function

No effect operates normally

Only the damaged disc will not function

Question 21 of 25

Question 22 of 25

22. What is the advantage of over head lines compared to underground cable?

Faults can be located easily

Not liable to the hazards from lightning discharges

No interference with the communication lines

Public safety is more

Question 22 of 25

Question 23 of 25

23. What is the name of the insulator used in O.H lines?

Post insulator

Strain insulator

Shackle insulator

Pin insulator

Question 23 of 25

Question 24 of 25

24. Which substation the transmission line voltage is stepped down to consumer supply voltage?

Mobile substation

Secondary substation

Distribution substation

Mining substation

Question 24 of 25

Question 25 of 25

25. What is the name of conductor used on overhead lines?

ACSR

Hard drawn copper

Galvanised iron

Aluminium

Question 25 of 25