Setting of Over Load Relay in Star Delta Starter

Depending on where the O/L's are fitted, the incoming line or one out going line.
105A or 61A

Before Main Contactors. (Supplay>OL Relay>MAin Contactor)

Generally in ΥΔ starters, the relay is within the delta, so it is set to the phase current, in your case 64A. Not always though, you need to check your connections.

Thanks

Go with 64

The Star/Delta starter is manufactured from three contactors, a timer and a thermal overload. The contactors are smaller than the single contactor used in a Direct On Line starter as they are controlling winding currents only. The currents through the winding are 1/root 3 (58%) of the current in the line. In your case 64A.....

There are two contactors that are close during run, often referred to as the main contactor and the delta contactor. These are AC3 rated at 58% of the current rating of the motor. The third contactor is the star contactor and that only carries star current while the motor is connected in star. The current in star is 1/root 3 (58%) of the current in delta, so this contactor can be AC3 rated at one third of the motor rating.

Set it to the same value as the full load current stated on the maker's name plate attached to it, particularly if it is still under manufacturer's warranty.

Swap any two of the three incoming phase connections.