Question 1 of 28

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

0 MΩ

500 MΩ

1 MΩ

Infinity

Question 1 of 28

Question 2 of 28

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

Insulation resistance test between conductors and earth

Insulation resistance test between conductors

Polarity test

Open circuit test

Question 2 of 28

Question 3 of 28

3. Where is system earthing done?

Domestic wiring installation

Electroplating installation

Generating station

Small industrial installation

Question 3 of 28

Question 4 of 28

4. Which earth resistance measurement method is illustrated?

Fall of potential

Fall of current

Potential dividing

Current dividing

Question 4 of 28

Question 5 of 28

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

Air conditioners

Halogen lamps

Geysers

Locomotives

Question 5 of 28

Question 6 of 28

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

3000 Watt

800 Watt

1500 Watt

2000 Watt

Question 6 of 28

Question 7 of 28

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

Fall of potential method

Fleming's left hand rule

Self induction

Mutual induction

Question 7 of 28

Question 8 of 28

8. What is the advantage of crimping?

Avoids loose connections

Reduces load current

Neat appearance

Easy replacement

Question 8 of 28

Question 9 of 28

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

Voltage drop = IR volt

Voltage drop = I/R volt

Voltage drop = I²R volt

Voltage drop = IR/2 volt

Question 9 of 28

Question 10 of 28

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

Open circuit in earth conductor

High value series resistance fault

Open circuit in neutral line

Short circuit between conductors

Question 10 of 28

Question 11 of 28

11. What test is carried out using a megger?

Insulation resistance test

Polarity test

Earth conductor continuity test

Earth electrode resistance test

Question 11 of 28

Question 12 of 28

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

3.5 Sq.mm

2.5 Sq.mm

1.5 Sq.mm

3 Sq.mm

Question 12 of 28

Question 13 of 28

13. What determines ohmmeter needle deflection in earth testers?

Current in current coil

Current in potential coil

Handle rotation speed

Ratio of currents in two coils

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Question 14 of 28

14. How can earth resistance be reduced?

Decreasing electrode length

Reducing pit depth

Providing double earthing

Increasing electrode length

Question 14 of 28

Question 15 of 28

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

Unconsciousness

Heart convulsions

Painful shock

No sensation

Question 15 of 28

Question 16 of 28

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

Keeping wet condition in earth pits always

Increasing the length of the electrode

Increasing the diameter of the earth electrode

Adding more sand and charcoal in earth pits

Question 16 of 28

Question 17 of 28

17. Advantage of stranded conductor over solid conductor?

Less voltage drop

More insulation resistance

More flexible

Cost is less

Question 17 of 28

Question 18 of 28

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

Providing parallel earthing

Providing plate earthing

Increasing conductor size

Earthing through impedance

Question 18 of 28

Question 19 of 28

19. Why is system earthing different from equipment earthing?

It protects from all circuit faults

It protects humans only

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

It's associated with current-carrying conductors

Question 19 of 28

Question 20 of 28

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

To decrease the voltage drop

To increase the voltage drop

To avoid electrolytic emf interference

To regulate the current

Question 20 of 28

Question 21 of 28

21. In which wiring installation is system earthing done?

Commercial wiring

Godown wiring

Substations

Domestic wiring

Question 21 of 28

Question 22 of 28

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

Deflecting torque proportional to current

Deflecting torque proportional to current²

No controlling torque

Air friction damping

Question 22 of 28

Question 23 of 28

23. Why is AC supplied for earth resistance measurement?

Protect meter coils

Provide electrostatic shield

Avoid electrolytic emf interference

Reduce meter current

Question 23 of 28

Question 24 of 28

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

Changes DC supply to AC

Converts AC to DC

Reverses generator rotation direction

Reverses DC polarity

Question 24 of 28

Question 25 of 28

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

Energy meter

Distribution board

Main switch

IC cut out

Question 25 of 28

Question 26 of 28

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

 

Continuity (or) open circuit test

Insulation resistance test between conductors

Insulation resistance test between conductors and earth

Polarity test

Question 26 of 28

Question 27 of 28

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

1/5 × Full load current

1/500 × Full load current

1/50 × Full load current

1/5000 × Full load current

Question 27 of 28

Question 28 of 28

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

Multimeter

Shunt-type ohmmeter

Series-type ohmmeter

Megger

Question 28 of 28