What are the protections are there for lines?

What are the protections are there for lines?  
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1 Answer

Answer :

Directional earthfault protection

Directional over current protection

Local breaker back up protection

Pole discrepancy

Main protection (distance protection)
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What are the built in protections provided in 415 V breaker?

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Why are children considered deserving of protections that other weak or powerless individuals do not get?

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Why, when birds sit on transmission lines or current wires doesn't get shock?

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Why non-return valves are provided in the steam extraction lines?

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ACSR (Aluminium Conductor Steel Reinforced) are used as (A) over head transmission lines. (B) super conductors. (C) fuse (D) underground cables.

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