Commercial EDM capacitance ranges

Anybody know the range of capacitance found in a typical commercial wire and sinker EDM?

What about the adjustability of the capacitance? How many different steps are usually available?

What about voltage? I've read 80 volts max is typical.

I assume if you are doing active spark control, you just put in enough capacitance to supply your longest
spark time and limit down from there. I'm trying to determine what those ranges are for spark time and max
voltages.

One more question ( for now ). Why is deionized water used in wire EDM when an oil product is used for sinker EDM?

thanks,
Larry E.

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