construction of ac and dc capacitors

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construction of ac and dc capacitors

Post by spindown » Tue Aug 04, 2009 3:29 am

Is there a difference in the construction of a conventional
capacitor used in dc circuits and those used with ac motors?
Thanks Paul

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Bob Scott
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Re: construction of ac and dc capacitors

Post by Bob Scott » Tue Aug 04, 2009 6:30 am

AC caps are high voltage, non-polarised, and should have low ESR (Equivalent Series Resistance). That is just off the top of my head.

But I'm just your regular Tom, Dick, or Harry. :mrgreen: For lots more information straight from the horse's mouth, take a look at Kemet's technical papers: ... l%20papers

I bet there is a plethora of information at other manufacturers' sites too. I bet everything you ever wanted to know about caps is out there somewhere. Check out "capacitor" in Wikipedia. I was drawn to some of the other related highlighted items like:

capacitor plague -
railguns -
memristor -

-=VA7KOR=- My solar system includes Pluto.

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Re: construction of ac and dc capacitors

Post by haklesup » Wed Aug 05, 2009 11:34 am

There sure is a difference. First in basic types for example ceramic caps are always non polarized and tantalum or electrolytics are generally polarized. If you come across a non polarized electrolytic, its actually 2 caps in one package manufactured in a symmetrical back to back type of fashon. Other manufacturing technologies result in polarized or non polarized caps. In most cases it has a lot to do with the insulator and conductor and their configuration and physical properties. You'll have to research a bit more deeply to find the reason and manufacturing diagram for each type.

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