Re: [CAD_CAM_EDM_DRO] Re: Power supply question.....A Good Cap info link

the point i am trying to make is that the voltag that you think you have on the caps is lower than what is actually across the caps in a brute linear supply.....(that is xfmr/diode/current limiting
resistor/filter cap)

Not to mention the really nasty little spikes you can get from motors and especially solenoids

now if you are using them as momentary 'batteries'.....where you are feeding them with a regulated voltage...that is different and you can prob use whatever the voltage is + whatever safety factor
you are comfortable with.

even so..in any commercial equipment with DC voltage...the rating is always or damn near always higher.

studleylee wrote:

> Good reading on Caps. See sections on:
> -Formation of the Anodic Films, Aging and Operating Limitations
>
> http://www.faradnet.com/deeley/book_toc.htm#toc
>
> faradnet.com/deeley/book_toc.htm#toc
>
> -Lee
>
> There are so many conflicting experts, it's best to state your
> information or question, read the responses and dont take anything
> personal, and be open to learning other points of view and
> experiences. Then keep whatever knowledge you've gained.
>
>
> > >
> > > There is some charge thing that goes on related to the chemistry
> of an
> > > electrolytic cap, such that a cap used below its rated voltage
> loses
> > > capacitance, almost in direct proportion to the rated voltage /
> applied
> > > voltage.
> > >
> > > That is, a 100 volt electrolytic cap used at 50 volts will,
> within a
> > > short period of time, have only half the capacitance.
> > >
> > > Therefore, against all good engineering instincts, a person
> should use
> > > an electrolytic cap rated for a voltage as close as possible to
> the
> > > expected DC voltage.
> > >
> > > Alan
> > >
> > > --
> > >
> > > Alan Rothenbush | The Spartans do not ask the
> number of the
> > > Academic Computing Services | enemy, only where they are.
> > > Simon Fraser University |
> > > Burnaby, B.C., Canada | Agix of
> Sparta
> > >
>
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