Protective Relays are the devices that detect abnormal conditions in electrical circuits by Measuring

A. Voltage 

B. Current 

C. Constantly the electrical quantity which differs during normal and abnormal condition 

D. None of the above 

Answer with Explanation:

C. Constantly the electrical quantity which differs during normal and abnormal condition 

Explanation:

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More Earthing MCQs with Full Explanation and Important Notes

1.  The neutral of the power system may be connected to the earth

2. Grounding of substation provides

3. Earthing is necessary to give protection against

4. Standard wire gauge used for earthing lead should not be thinner than

5. What should be the value of earthing resistance for large power stations?

6. The earthing wire should have

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9. A ground wire is used to

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11. From the point of view of safety, the resistance of the earthing electrode should be