Re: [CAD_CAM_EDM_DRO] Commercial EDM capacitance ranges

Larry,
I will try to answer best as I can.
Industrial machines are huge. I have repaired wire and plunge units.
The manufacturers **refuse** to supply any internal docs.
Opening one of these up reveals an enormouse array of electronics.
Which capacitor?. There are many. I have never gotten to the level of
knowlege (or needed to) to discover the output circuits.
All is computer controlled, in any case.
The water for the flushing thru the cut in the wire EDM is just tap water
recirculated and filtered for use as the local water is very mineral free.
It splashes about the work area and drains back into the 'dirty' tank.
The plunge EDM is another matter and an entirely different operation.
This must be submerged to control the intense sparking on electrodes having
much larger surface areas than wire (.011" dia). Quenching fire and smoke
as well as flushing movements are the usual method. A type of orderless oil
is pumped into the well on startup and automatically drained on stop.
Even so, a lot of fire is seen to erupt from under an electrode.
An occasional puff will make it to the surface.
RichD

Larry Edington wrote:

>
> 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.