How can i calculate resistance offered by induction motor when in star and delta connection and if I know winding pattern, power of a motor and number of poles?
The effective impedance of an induction motor varies with load, applied voltage and frequency. If you don't know the full-load current and power factor determined by the manufacturer, you can not calculate them. To determine the values of motor's equivalent circuit components, no-load and locked rotor tests must be performed. Various versions of the step-by-step procedure can be found on the internet.