hello everybody

if we install capacitor across motor we have to make necessary adjusments in the overload relay

have we to adjust overlaod relay setting if we provide the same capcitor before overload relay and contactor(in the same starter -dol.ie after isolator) ram

Hello ram

Ideally, you should connect the capacitor before the overload relay so that the overload relay sees all the current going into the motor.
If you connect the capacitance after the overload relay, you will need to make adjustments to it's settings and you will be more prone to overload trips due to harmonic bursts into the capacitor etc.

Best regards,
Mark.