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Re: capacitor fuzz





---------- Forwarded message ----------
Date: Sun, 19 Oct 1997 23:38:00 -0700
From: Bert Hickman <bert.hickman-at-aquila-dot-com>
To: Tesla List <tesla-at-pupman-dot-com>
Subject: Re: capacitor fuzz

Tesla List wrote:
> 
> ---------- Forwarded message ----------
> Date: Sun, 19 Oct 1997 17:44:39 -0400
> From: Someone <fox-at-netunlimited-dot-net>
> To: Tesla List <tesla-at-pupman-dot-com>
> Subject: Re: capacitor fuzz
> 
> <SNIP>
> > will have that problem. The solution is to not use foil at all, but
> > rather
> > immerse in electrolyte (saltwater in your case).
> >
> > Hope this helps.
> > Fr. Tom McGahee
> 
> i did this and it works. i put an
> inch thick layer of 10 w 30 on top of the water and whenever i turn on
> the circuit (this is just the hv source a gap and the caps in series)
> the oil likes to dance around the neck of the bottles. also the oil
> turned from a clear viscous brown to a light opaque caramel colour. any
> info about this? it still works fine tho.


Well, here's the scoop on the goop...

According to J. B. Birks (Modern Dielectric Materials, Academic Press,
1960, page 51) electrical stresses degrade mineral oils, creating the
phenomenon of "waxing". Under prolonged electron bombardment in ionizing
cavities, mineral oil polymerizes, forming a wax-like substance. Under
high stress, gases start to evolve (mostly hydrogen), creating gas
cavities. This occurs when the electrical stresses reach the order of 50
KV/cm or more. Under these conditions, small discharges, called
microdischarges, start further breaking down the oil. The more
"paraffinic" the oil, the greater this tendency. For this reason,
transformer and capacitor oils tend have a fair amount of aromatic
(napthenic) hydrocarbons in the mineral oil blend. 

10W-30 motor oil may have a higher paraffinic content than transformer
oil or USP mineral oil, and may tend to be more prone to this particular
problem.

Safe waxin' and wanin' to you...

-- Bert --