Answer Posted / ranjit kumar mallick
In induction motor the rotor movement is due to it's
interaction with the stator resultant rotating magnetic
field flux and the resultant magnetic flux is due to the
three phase closed circuit. Once we ground the star point
the resultant magnetic field will drop and it becomes
extremely dangerous in case of fault as motor will run at
low speed without triping due to the current path available
to ground.So it will draw high current
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