In a 3 phase squirrel cage induction motor why does rotor
rotate?
will 3 phase transformer rotate like a motor if it is
placed on bearings and powered up? give reason

Answer Posted / ravi693

In 3 phase squirrel cage induction motor, due to electro
magnetic induction emf is induced in rotor circuit. This
emf produced the rotor magnetic field. We have alreade
stator magnetic field. A revolving magnetic field set up
and motor start running.

If 3 phase t/f is placed on bearings and powered up. It
will not rotate due to following reasons.
1) T/F secondary is open circuited and small current is in
secondary side. Less field is there. No revolving field is
set up.
2) Design parameters are there. Which did not produce
revolving magnetic field.

Is This Answer Correct ?    29 Yes 18 No



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