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Subject: Re: Capacitor Voltage Ratings

From: "bbluthang" <jumpswine@...>
Date: 2010-06-30

yes an earth connection is a very good idea!

--- In tubesynthdiy@yahoogroups.com, Kyle Stephens <lightburnx@...> wrote:
>
> So I got a variac the other day, which many sites recommend for use with reforming caps.
>
> It's a neat piece of equipment to have lying around too - as the guy who sold it to me said, it has a Frankenstein quality to it.
>
> That said, it's quite old (it's called an "Adjust-A-Volt" if that gives you any idea), and has only two prong connectors for the line in and out.
>
> Should I bother getting one of those two to three prong adapters, like this:
>
> http://ep.yimg.com/ca/I/trianglecables-site_2113_308000194
>
> And tie the ground lug to the chassis? And tie that to the wall outlet ground as well then?
>
>
> _Kyle
>
> --- On Sat, 6/19/10, sasami@... <sasami@...> wrote:
>
> From: sasami@... <sasami@...>
> Subject: Re: [tubesynthdiy] Capacitor Voltage Ratings
> To: tubesynthdiy@yahoogroups.com
> Date: Saturday, June 19, 2010, 12:48 AM
>
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> Â
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> If they have been sitting around unused for many years, yes reforming would
>
> be a good idea. I so no reason why you can't do it in the supply - as you
>
> say, raising the voltage slowly over time. The reason for that is to stop
>
> heat build-up that could damage them.
>
> I'm sure there is a lot more on reforming on the web, alond with some
>
> reforming circuits, from people with a lot more experience on the subject
>
> than me.
>
>
>
> Ken
>
>
>
> >I see - makes sense. Eric's designs didn't have a rating otherwise I'd have
>
> gone by that. Even if they were there, knowing 'why' is good too.
>
> >
>
> >A follow up capacitor question: the big electrolytics I picked up for my
>
> power supply, as per the design on your site Ken, from physical inspection
>
> at least seem recent enough (ranging from ~5-30 years old), though should I
>
> bother reforming them? Could I do that while burning in the fully built
>
> supply, slowly raising the input voltage to 120V?
>
> >
>
> >My thanks sir!
>
> >
>
> >
>
> >_Kyle
>
> >
>
> >--- On Fri, 6/18/10, sasami@... <sasami@...> wrote:
>
> >
>
> >From: sasami@... <sasami@...>
>
> >Subject: Re: [tubesynthdiy] Capacitor Voltage Ratings
>
> >To: tubesynthdiy@yahoogroups.com
>
> >Date: Friday, June 18, 2010, 4:54 PM
>
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> > The "greater than the DC voltage it will see, plus at least 20%
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> spare" would
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> >
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> >be the first rule. Be aware that a capacitor can see more than the power
>
> >
>
> >rail voltage in some circumstances (i.e charged in one direction, then
>
> >
>
> >having the opposite voltage applied it). Double the DC voltage is good. The
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> >
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> >value specified on the circuit diagram (if present) is ideal.
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> >
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> >
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> >
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> >Ken
>
> >
>
> >__________________________________________________________
>
> >
>
> >Ken Stone sasami@... otherunicorn@...
>
> >
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> >Modular Synth PCBs for sale <http://www.cgs.synth.net/>
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> >
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> >Australian Miniature Horses & Ponies <http://www.blaze.net.au/~sasami/>
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> ><table cellspacing="0" cellpadding="0" border="0" ><tr><td valign="top"
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> style="font: inherit;">I see - makes sense. Eric's designs didn't have a
>
> rating otherwise I'd have gone by that. Even if they were there, knowing
>
> 'why' is good too.<br><br>A follow up capacitor question: the big
>
> electrolytics I picked up for my power supply, as per the design on your
>
> site Ken, from physical inspection at least seem recent enough (ranging from
>
> ~5-30 years old), though should I bother reforming them? Could I do that
>
> while burning in the fully built supply, slowly raising the input voltage to
>
> 120V?<br><br>My thanks sir!<br><br><br>_Kyle<br><br>--- On <b>Fri, 6/18/10,
>
> sasami@... <i>sasami@...</i></b>
>
> wrote:<br><blockquote style="border-left: 2px solid rgb(16, 16, 255);
>
> margin-left: 5px; padding-left: 5px;"><br>From: sasami@...
>
> sasami@...<br>Subject: Re: [tubesynthdiy] Capacitor
>
> Voltage Ratings<br>To:
>
> > tubesynthdiy@yahoogroups.com<br>Date: Friday, June 18, 2010, 4:54
>
> PM<br><br><div id="yiv2065612811">
>
> >
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> >
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> >
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> >
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> ><span style="display: none;"> </span>
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> >
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> >
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> >
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> > <div id="ygrp-text">
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> >
>
> >
>
> > <p>The "greater than the DC voltage it will see, plus at least 20%
>
> spare" would<br>
>
> >be the first rule. Be aware that a capacitor can see more than the power<br>
>
> >rail voltage in some circumstances (i.e charged in one direction, then<br>
>
> >having the opposite voltage applied it). Double the DC voltage is good. The<br>
>
> >value specified on the circuit diagram (if present) is ideal.<br>
>
> ><br>
>
> >Ken<br>
>
> >__________________________________________________________<br>
>
> >Ken Stone <a rel="nofollow" ymailto="mailto:sasami%40hotkey.net.au"
>
> target="_blank"
>
> href="/mc/compose?to=sasami%40hotkey.net.au">sasami@...</a> <a
>
> rel="nofollow" ymailto="mailto:otherunicorn%40virginbroadband.com.au"
>
> target="_blank"
>
> href="/mc/compose?to=otherunicorn%40virginbroadband.com.au">otherunicorn@vir
>
> ginbroadband.com.au</a><br>
>
> >Modular Synth PCBs for sale <<a rel="nofollow" target="_blank"
>
> href="http://www.cgs.synth.net/">http://www.cgs.synth.net/</a>><br>
>
> >Australian Miniature Horses & Ponies <<a rel="nofollow"
>
> target="_blank"
>
> href="http://www.blaze.net.au/%7Esasami/">http://www.blaze.net.au/~sasami/</
>
> a>><br>
>
> ><br>
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> ></p>
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>
> __________________________________________________________
>
> Ken Stone sasami@... otherunicorn@...
>
> Modular Synth PCBs for sale <http://www.cgs.synth.net/>
>
> Australian Miniature Horses & Ponies <http://www.blaze.net.au/~sasami/>
>