Answer / nithyanandam

0.8A per sq.mm for Al. and 1.75A per sq.mm for Copper..

1hp motor takes full load current of 1.5A
1 Kw motor takes full load current of 1.99999A.

Therefore,
90 kw motor takes full load current of 180A.
so, 225 sq.mm aluminium or 102.8 sq.mm copper is the
suitable for 90kw motor

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