I've selected 230/400V motors (delta/star) and corresponding 400V VFDs for pump motors. Now I've been asked why I haven't selected 400/690V motors (delta/star), that are the standard and usually connected in delta. The manufacturer says there that the both motors types will consume (approx.) 8A at 400V and there is no special requirement for the torque.
Is anyone seing an advantage to have the 400/690V motors instead of the other ones?