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Re: win tesla vs. JHCTES

Hi Bill,

> Date forwarded: Tue, 15 Sep 1998 17:07:02 -0600
> Date sent:      Tue, 15 Sep 1998 16:35:56 -0600
> To:             tesla-at-pupman-dot-com
> Subject:        Re: win tesla vs. JHCTES
> Forwarded by:   tesla-at-pupman-dot-com
> From:           Tesla List <tesla-at-pupman-dot-com>

> Original Poster: "Bill Layer" <b.layer-at-vikingelectronics-dot-com> 
> 
> Hi John,
> 
> I guess I need some clarification on something. 
> 
> >Regarding the 60ma NST, this often causes great confusion because
> >a 60ma NST can deliver a lot more than 60ma, if a resonant charging
> >sized capacitor is used.  So if someone says they got let's say a 60"
> >spark from a 60ma NST, they may actually be drawing 120ma or even 
> >more from the transformer.  This helps to explain their results.  The 
> >60ma should be thought of as transformer rating only, rather than an
> >actual amount of current draw.
> >
> >Bottom line, the record for a 60ma NST, and the record for a true 60ma
> >current draw (from a 60ma NST), would be very different animals.
> 
> By all the previous posts I've read, NSTs are current limited to their
> nameplate spec. That is, a 60mA NST will do 60 mA into a dead short. How is
> the limiting accomplished: inductive or resistive?
 
90% inductive.

> I would believe that higher voltages could be produced, which in turn might
> constitute higer VA outputs for the same (limited) current. It would seem
> that you are suggesting tht these higher induced voltages will push
> proportionally more current through the sec, when the voltages are actually
> an effect of the nominal currents...
> 
> Could someone help enlighten me here?>

If you choose a capacitor such that its reactance at Fmains = the 
reactance (V/I) of the transformer, a resonant condition exists. In a 
half cycle of charging (+ve peak to -ve peak) you can get around 70%
higher voltage on the cap than the RMS rating. In theory, a lossless
charging system will deliver 2Vrms but a NST is far from lossless. 

     The resonant condition is signalled by slow main gap firing with 
a variac setting of 30% or so.

     Re the 60mA: that is an RMS rating. The transformer should be 
able to deliver around 85mA or so peak.

Malcolm