Answer Posted / electrical

V=Eb+IaRa,Eb=back emf

At starting there is no back Emf
And V (Normal Supply Voltage)=220V(single Phase)
Ia = Armature Current
Ra = Armature resistance(Usually less (.2 to .5 ohms)

From the Above equation,
Ia = (V-Eb)/Ra
Since Eb is Zero, the above eqn will become
Ia = V/Ra (220/0.5 = 440A)
So at starting the current thru the armature is very high
to minimise this we are using the starters.

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