If you mean the reduced voltage wye-delta starting method there is no general answer. It depends on the what kind of voltage sag is allowed by the local power company or the tolerable one that will work in the immediate area.
In all cases wye-delta starters are inferior to any other reduced voltage starting method. It often causes many problems with no benefit at all.
Way Out West, for motors operated at the facility service voltage, utilities generally have pat rules on this {like, say 40Hp} but for service at medium or high voltages, it’s subject to engineering review.
I have worked on EU-originated process equipment where Y-D starting was applied to as low as 3Hp.
