Why 100% winding protection is felt essential for main generator stator E/F protection? (Used in NAPS onwards?)

Why 100% winding protection is felt essential for main generator stator E/F protection? (Used in NAPS onwards?)  
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1 Answer

Answer :

At MAPS 4% of winding is not protected. Earlier felt that the Electro magnetic stress due high external fault currents near 4% of neutral may not be high to cause E/F here. But now felt that the mechanical stress can leads to E/F. 
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Related questions

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