Calculating Relay Range for Star Delta Starter

Let us assume the following:

Motor rating 30 kW

Efficiency 100 %

Power factor=0.8

applied Voltage=415 V (L-L)

The full load Line current would be(Iline) =(30*1000)/(415*0.8*1.732)=52 .17 Amps

The phase current would be(Iphase) =Iline/1.732=30.1 Amps

In a standard Star Delta starter the thermal over load relay would be in Delta formation, therefore the over load relay range should 21-36 amps.You can set the range from 70 % to 120 %

thanks for giving logical answer

what to be the relay amps to be set for idial condition

Or just take the shortcut, especially since you failed to provide details on the motor other than the kW rating.

Read the motor nameplate, multiply the FLC x .58