Re: [CAD_CAM_EDM_DRO] Re: Photoflash capacitors for EDM use

turbulatordude wrote:

>I reapeatly come across 12 and 24 V power supplies from phone or
>intercom systems. often 30 amp or larger supplies.
>
>The ones I looked at today had 10 volt Caps so I just kept walking.
>
>Any suggestions what I might look for out of a switching power
>supply ?
>
>

Almost all switching power supplies have 200 V or higher rated capacitors in
the INPUT side, for smoothing the rectified AC line. Most have 2 of them,
as they use a doubler circuit on 120 V to produce 340 V DC across 2 of these
caps. I'm not sure they are really much use for RC-type EDM, I think they
are way too large. I used 1.5 - 3 uF for my EDM, although I can go up to
20 uF by flipping switches, that was WAY too much and just blasted
everything,
including the electrode.

Other than that, there are lots of parts - rectifiers, inductors, other
capacitors,
high frequency transformers, diodes that might be useful for building the
DC part of an EDM supply, etc.

Jon