What factors determine the dimensions of a 500 kVA oil-filled transformer?

Dimensions depend on voltage ratio, insulation levels (BIL), cooling class (ONAN, ONAF), allowable temperature rise, core design, tank and radiator sizing, and accessory package. Higher primary voltage and higher insulation levels typically increase clearances and tank size. Environmental requirements, sound limits, transport constraints, and manufacturer design philosophy also change dimensions. Because 500 kVA can be built in many voltage configurations, there is no single standard footprint, always use the specific manufacturer drawing.