A 3-phase, 400 votts, 50 Hz, 100 KW, 4 pole squirrel cage induction motor with a rated slip of 2% will have a rotor speed of (A) 1500 rpm (B) 1470 rpm (C) 1530 rpm (D) 1570 rpm

A 3-phase, 400 votts, 50 Hz, 100 KW, 4 pole squirrel cage induction motor with a
rated slip of 2% will have a rotor speed of
 (A) 1500 rpm (B) 1470 rpm
 (C) 1530 rpm (D) 1570 rpm
by

1 Answer

Answer :

Ans: B
N = NS (1-S) and NS =120 f / p
=120 x 50 /4 = 1500 rpm
∴N= 1500 (1-0.02) =1470 rpm
by

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