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A 3-phase, 2 pole, 11 kV, 10000 kVA alternator has earthed neutral through a resistance of 7.0Ω. The machine has current balance protection which operates if out of balance current exceeds 20% of full load. Determine %age of winding protected against earth fault (1) 10.6% (2) 11.6% (3) 10.9% (4) 11.2% 

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