# RE: Request for math (ballasting) (fwd)

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---------- Forwarded message ----------
Date: Fri, 17 Jul 1998 07:43:18 -0700
From: "Basura, Brian" <brian.basura-at-unistudios-dot-com>
To: 'Tesla List' <tesla-at-pupman-dot-com>
Subject: RE: Request for math (ballasting) (fwd)

Dr. Resonance,

If I understand your explanation correctly that is why people cut a
variac and use it as a variable inductor (it's then a c shaped core).  I
was going to ask if a modified 400hz variac would work as an inductor
but It would probably saturate at 60 hz.

My other thought was to take some 1/2" metal strapping tape (the kind
you strap machinery to pallets with), make about 6 rolls, stack them
side by side, insulate, wind wire, then cut a slot through the entire
core. My problem is I don't know how to determine the size of the core.

One more question, what do you use for your .5ohm / ?Kwatt resistance?

Thanks.  I've learned a lot from lurking here.

Brian  B
> ----------
> From: 	Tesla List[SMTP:tesla-at-pupman-dot-com]
> Sent: 	July 16, 1998 8:21 PM
> To: 	tesla-at-pupman-dot-com
> Subject: 	Re: Request for math (ballasting) (fwd)
>
>
>
> ---------- Forwarded message ----------
> Date: Thu, 16 Jul 1998 17:12:03 -0600
> From: "D.C. Cox" <DR.RESONANCE-at-next-wave-dot-net>
> To: Tesla List <tesla-at-pupman-dot-com>
> Subject: Re: Request for math (ballasting) (fwd)
>
> to: Mike
>
> It probably won't work very well.  You need ideally a closed C-core
> with a
> 0.120 inch gap and around 130-140 turns for a total series inductance
> of
> around 40 milliHenries.  Your open core would requires a large
> magnitude
> more turns -- probably around 1,000 and then still might require a
> series
> resistance of 0.5 Ohm.  The straight core inductors do not work very
> well
> -- we made one years ago and have long since switched to the gapped
> C-core
> design.  We also still use a 0.5 Ohm series resistance to smooth of
> the
>
> DR.RESONANCE-at-next-wave-dot-net
>
>
> ----------
> > From: Tesla List <tesla-at-pupman-dot-com>
> > To: tesla-at-pupman-dot-com
> > Subject: Request for math (ballasting) (fwd)
> > Date: Wednesday, July 15, 1998 10:06 PM
> >
> >
> >
> > ---------- Forwarded message ----------
> > Date: Wed, 15 Jul 1998 20:39:50 -0700 (PDT)
> > From: Michael Baumann <baumann-at-proton.llumc.edu>
> > To: Tesla List <tesla-at-pupman-dot-com>
> > Subject: Request for math (ballasting)
> >
> > I've got this insane idea to build my own reactor to limit current
> > to my (soon to be ordered) pig.
> > Call me nuts, but there is something about kludging a welder
> > that doesn't seem elegant to me.
> >
> > Anyway, I am hoping that someone out there that has experience
> > with the building of iron core inductors can send me the appropriate
> > equations.
> >
> > My idea is to take some PVC ( I have 2" and 3.5" ) and stuff it with
> > iron rods (either round stock or welding rods, not sure which yet)
> then
> > wind xxx turns of 10AWG on that, with taps at various points to
> > give me different power levels.  Hopefully this is not too crazy,
> and
> > someone out there can point me to the math needed to compute
> > the approximate inductance of the iron core coil.
> >
> > Thanks
> >
> >
> > --
> > Michael Baumann  Optivus Technology Inc.|Loma Linda University
> Medical
> Center
> > San Bernardino, California. (909)799-8308 |Internet:
> baumann-at-llumc.edu
> >
>

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