Factory Supply Voltage

11kV here. Or maybe 33kV on occasions.

It depends on what part of the world you are talking about. Without a doubt, it will be three phase and then it depends on the kind of equipment that will be used.

400V 50Hz three phase. That is THE most common factory supply voltage here.

Power supply to factory depends upon the factory sizes and the load installed at the factory. Small scale factory usually will be 415V or 11KV (if you have a 11KV/415V transformer installed at your factory where you need much higher power capacity for your factory).

Medium size factory will be 11KV or 33KV where they have serval transformers to step down the voltage for certian machines usage.

Of course, big factory like steel mills or other big MMC manufacturing plant will be 11KV, 33KV or even 132KV system.

We have all of 132KV coming over here

It all depends on the load the factory needs, based on that the KV at the internsl substation is decided.

Depend on factory load capacity and bus bar capacity. example: your bus bar is 2000A, your factory Load (peak) is 15MVA then the voltage should be 7.5KV.