Re: Ballasting question

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Charles Hobson by way of Terry Fritz <twftesla-at-qwest-dot-net>" <charles.a.hobson-at-btinternet-dot-com>

----- Original Message -----
From: Tesla list <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Monday, June 25, 2001 11:15 PM
Subject: Ballasting question


> Original poster: "Michael O. Poley by way of Terry Fritz
<twftesla-at-qwest-dot-net>" <mpoley-at-mindspring-dot-com>
>
> Okay, since I got such a fast response on the other question, let me ask
> this...
>
> Can someone explain the theory and practice of "ballasting"?  I'm familiar
> enough with the physics behind the Tesla coil, but the term has been
> bandied about a lot and I haven't seen anything explaining what exactly
> ballasting is nor when it should be done, and when it is acceptable to
> overlook it.
>
> Mike
>
> Michael O. Poley
> mpoley-at-mindspring-dot-com

Hi Mike,

I hope you get some good clear answers to your question. I am looking
forward to them also. My understanding for ballast is limited relative to
Tesla Coil application, but as I see it, the ballast in needed for systems
using "pole pigs", transformers where if the secondary is shorted, "like
with a spark gap" , the primary see the short also. Hence, the minimum
inductance needed in series with the primary appears to be a function of the
transformer's maximum VA rating. (You experienced guys please correct me on
this if I am wrong)

But that's not where it seems to stop. Between bangs the transformer is
looking at the Tesla Coil's primary tank circuit capacitor Cp. Thus, there
appears to be an LC series circuit comprising Cp and L where L = ballast
inductance x N^2 (pole pig turns ratio). Please again you experienced guys,
jump in and correct me if this is wrong. If I am right in this, then the
ballast inductance can be increased from its minimum value to where it will
resonate with Cp at 50/60Hz. Again the transformer primary circuit will
behave as a short circuit at resonance. So--- some value between the minimum
inductance and the resonating inductance needs to be worked out. I think
inductances greater than the resonant value can also be considered.(Please
again you experts, help!!) There seems again here to be computer programs
around to work this all out, but I would like to see and understand the
algorithms used.

I hope this is helpful here or has stirred up better and more correct
answers to your question.

Chuck