An 8 pole, 50 Hz, 3-phase IM is loaded to a poing where pull
out torque will occur. The rotor resistance per phase is 0.3
ohm and motor stalls at 650 rpm. The rotor frequency at
maximum torque point is
A 3.33% B 4.44%
C 5.55% D 6.66%
Answer Posted / jay laruja
-slip at 650 rpm
120fs/p
= (120 x 50) / 8
= 750
slip = (Ns + Nr) / Ns = 0.133
fr = s x fs = 0.13 x 50 = 6.667%
there you go buddy ;)
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