Question 1 of 28

1. Advantage of stranded conductor over solid conductor?

More insulation resistance

Less voltage drop

Cost is less

More flexible

Question 1 of 28

Question 2 of 28

2. Which earth resistance measurement method is illustrated?

Fall of current

Fall of potential

Potential dividing

Current dividing

Question 2 of 28

Question 3 of 28

3. Why is system earthing different from equipment earthing?

It protects from all circuit faults

It's connected to non-current-carrying metal parts

It protects humans only

It's associated with current-carrying conductors

Question 3 of 28

Question 4 of 28

4. What determines ohmmeter needle deflection in earth testers?

Handle rotation speed

Current in current coil

Current in potential coil

Ratio of currents in two coils

Question 4 of 28

Question 5 of 28

5. Which method is used to reduce earth resistance value in an existing earth pit?

Adding more sand and charcoal in earth pits

Increasing the length of the electrode

Increasing the diameter of the earth electrode

Keeping wet condition in earth pits always

Question 5 of 28

Question 6 of 28

6. What test is carried out using a megger?

Polarity test

Insulation resistance test

Earth electrode resistance test

Earth conductor continuity test

Question 6 of 28

Question 7 of 28

7. What is the permissible leakage current in domestic wiring installation?

1/5 × Full load current

1/5000 × Full load current

1/500 × Full load current

1/50 × Full load current

Question 7 of 28

Question 8 of 28

8. In which wiring installation is system earthing done?

Substations

Commercial wiring

Godown wiring

Domestic wiring

Question 8 of 28

Question 9 of 28

9. How can earth resistance be reduced?

Reducing pit depth

Decreasing electrode length

Providing double earthing

Increasing electrode length

Question 9 of 28

Question 10 of 28

10. Which principle does the earth resistance tester work on?

Self induction

Mutual induction

Fall of potential method

Fleming's left hand rule

Question 10 of 28

Question 11 of 28

11. Why is AC required to measure earth resistance using an earth resistance tester?

To regulate the current

To increase the voltage drop

To decrease the voltage drop

To avoid electrolytic emf interference

Question 11 of 28

Question 12 of 28

12. What is the formula to find voltage drop in an AC single-phase wiring circuit?

Voltage drop = I/R volt

Voltage drop = IR volt

Voltage drop = IR/2 volt

Voltage drop = I²R volt

Question 12 of 28

Question 13 of 28

13. Where are service connection supply leads connected in a consumer main board?

Main switch

Distribution board

IC cut out

Energy meter

Question 13 of 28

Question 14 of 28

14. What is the megger reading in a dead short wiring installation?

500 MΩ

Infinity

0 MΩ

1 MΩ

Question 14 of 28

Question 15 of 28

15. What is the function of current reverser in earth resistance testers?

Changes DC supply to AC

Reverses generator rotation direction

Reverses DC polarity

Converts AC to DC

Question 15 of 28

Question 16 of 28

16. What type of test is conducted in domestic wiring installation?

 

Continuity (or) open circuit test

Insulation resistance test between conductors and earth

Polarity test

Insulation resistance test between conductors

Question 16 of 28

Question 17 of 28

17. How to control harmonic distortions in neutral connections per IE rules?

Earthing through impedance

Providing plate earthing

Increasing conductor size

Providing parallel earthing

Question 17 of 28

Question 18 of 28

18. For which electrical equipment are 'L' series type MCBs used?

Halogen lamps

Locomotives

Geysers

Air conditioners

Question 18 of 28

Question 19 of 28

19. What type of test is performed in wiring installation?

Polarity test

Insulation resistance test between conductors and earth

Insulation resistance test between conductors

Open circuit test

Question 19 of 28

Question 20 of 28

20. What is the advantage of crimping?

Reduces load current

Easy replacement

Neat appearance

Avoids loose connections

Question 20 of 28

Question 21 of 28

21. Why is AC supplied for earth resistance measurement?

Avoid electrolytic emf interference

Reduce meter current

Protect meter coils

Provide electrostatic shield

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Question 22 of 28

22. What happens when a person receives a 20mA shock current?

No sensation

Heart convulsions

Unconsciousness

Painful shock

Question 22 of 28

Question 23 of 28

23. What causes lamps to glow dim and motors to run slow in domestic wiring?

Open circuit in neutral line

Short circuit between conductors

High value series resistance fault

Open circuit in earth conductor

Question 23 of 28

Question 24 of 28

24. Where is system earthing done?

Generating station

Domestic wiring installation

Small industrial installation

Electroplating installation

Question 24 of 28

Question 25 of 28

25. What is the minimum size of copper earth continuity conductor used in single-phase domestic wiring as per BIS?

3 Sq.mm

3.5 Sq.mm

2.5 Sq.mm

1.5 Sq.mm

Question 25 of 28

Question 26 of 28

26. Why does megger's pointer not stabilize at zero when unused?

No controlling torque

Deflecting torque proportional to current

Deflecting torque proportional to current²

Air friction damping

Question 26 of 28

Question 27 of 28

27. Which instrument is used to test new domestic wiring installation?

Series-type ohmmeter

Multimeter

Megger

Shunt-type ohmmeter

Question 27 of 28

Question 28 of 28

28. What is the maximum permissible load for a power sub-circuit as per IE rules?

1500 Watt

3000 Watt

2000 Watt

800 Watt

Question 28 of 28