A 3 phase, 10 kW, 400 V, 4 pole, 50 Hz, star connected induction motor draws 20 A on full load. Its no load and blocked rotor test data are given below : No Load test : 400V 6 A 1002 W Blocked Rotor test : 90 V 15 A 762 W Neglecting copper loss in no Load test and core loss in Blocked Rotor test, estimate motor 's full load efficiency.

A 3 phase, 10 kW, 400 V, 4 pole, 50 Hz, star connected induction motor

1.	A 3 phase, 10 kW, 400 V, 4 pole, 50 Hz, star connected induction motor draws 20 A on full load. Its no load and blocked rotor test data are given below : No Load test : 400V 6 A 1002 W Blocked Rotor test : 90 V 15 A 762 W Neglecting copper loss in no Load test and core loss in Blocked Rotor test, estimate motor 's full load efficiency.
A.	76%
B.	81%
C.	82.4%
D.	85%
Answer» C. 82.4%

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