Re: Dielectric oil for a new capacitor (fwd)

["Tesla list" <tesla@xxxxxxxxxx>]

---------- Forwarded message ----------
Date: Tue, 19 Jun 2007 13:19:37 -0600 (MDT)
From: Chip Atkinson <chip@xxxxxxxxxx>
To: Tesla list <tesla@xxxxxxxxxx>
Subject: Re: Dielectric oil for a new capacitor (fwd)

For the rewound NST that I sunk in oil in my own plexiglas case, I used
peanut oil.  Somewhere I read that it was used in the olden days and it
was easy to get at the grocery store.  

The remaining tar on the NST dissolved into the oil making it a murky dark
grey but that nst has worked for a long time.  I'd really hate to smell
the oil though because I bet it's beyond rancid. :-}

Chip

On Tue, 19 Jun 2007, Tesla list wrote:

> 
> ---------- Forwarded message ----------
> Date: Tue, 19 Jun 2007 12:00:04 -0700
> From: Jim Lux <jimlux@xxxxxxxxxxxxx>
> To: Tesla list <tesla@xxxxxxxxxx>, tesla@xxxxxxxxxx
> Subject: Re: Dielectric oil for a new capacitor (fwd)
> 
> At 10:17 AM 6/19/2007, Tesla list wrote:
> 
> >---------- Forwarded message ----------
> >Date: Tue, 19 Jun 2007 11:31:34 EDT
> >From: ashumate3@xxxxxxx
> >To: tesla@xxxxxxxxxx
> >Subject: Re: Dielectric oil for a new capacitor (fwd)
> >
> >About mineral oil for horses. Do not use it. You have to remember you are
> >using this with high voltage and what they sell for show horses does not go
> >through quality and dielectric test.
> 
> The typical laxative USP white mineral oil (which is what you get at 
> the feed store) might be reasonably dry and clean, depending on where 
> and how it was packaged.  If they fill the gallon bottles themselves 
> from the drum in the back....
> 
> However, if it's filled appropriately, it's not far off the real 
> thing, and if it's cheap and available...
> 
> You can dry it with some dessicant or by carefully heating it to 
> drive off the moisture.
> 
> Most amateur HV gear isn't well sealed enough to agonize about water 
> content.  It's usually vented and exposed to the atmosphere, and so, 
> will pick up moisture.  Yes, the breakdown voltage will be slightly 
> less, but for most amateur applications, you're using the oil as a 
> coolant and to displace air (i.e. running a NST sunk in a tank of 
> oil) in which case even the crummiest oil has better insulating 
> properties than the air it replaced.
> 
> If you're using it in something where moisture content and 
> cleanliness is important (i.e. you're filling under a vacuum), then 
> the USP oil is probably not what you want.  If you've invested the 
> time and money in the gear for an application where the difference is 
> important, you'll have no problem tracking down the insulating oil.
> 
> The big chemical difference (as opposed to water content) between 
> things like Diala AX and USP White Mineral Oil is that the AX has an 
> inhibitor in it to prevent spoilage.  The viscosity is also different 
> which can be very important in cooling systems that depend on 
> thermosyphoning over wide temperature ranges.  If you're filling that 
> 1 MVA transformer with the fins, you want the real deal.
> 
> Cost wise, they're both almost exactly the same price in large 
> quantities.  It's the cost to put it into small containers and retail 
> it that is different.
> 
> 
> There's also more "geek cred" from having that bright yellow pail of 
> Diala AX instead of a case of quart bottles of mineral oil from the drugstore.
> 
> >Ideally before you use oil it should be
> >tested but many out there are not equipped to do this type of testing so the
> >next best thing is to be sure of your source.
> >
> >Al Shumate
> >
> >
> >
> >************************************** See what's free at http://www.aol.com.
> 
> 
> 
> 
>