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More SRSG questions (was: Re: Finally got around to =?iso-8859-1?Q?sync=B4ing?= my async motor)



Hi Terry, John, Viv, all,

>Original Poster: Terry Fritz <twf-at-verinet-dot-com>
>
>At 05:32 PM 4/24/99 +0100, you wrote:
>>SNIP
>>
>>Unfortunately I have just destroyed my NST using it :-(
>>By the way my NST is Italian and potted.
>>Viv Watts UK
>>
>Resonant charged NST systems will develop huge voltages across the primary
>cap and transformer.  This super high voltage will easily destroy the cap
>and/or transformer.  In a static gap system, the gap will ALWAYS fire and
>save the day.  However, rotary gap systems can easily not fire in time to
>prevent the voltage buildup and BANG!... there goes the transformer.
>
>The solution is simple, just have a static safety gap across the
>transformer or cap.  If the rotary decides not to fire, the safety gap will
>step in and drain the voltage before it reaches destructive levels.

Agreed (except I would use a SSG across the cap AND the xformer to
provide a "solid" path to ground for the "too many electrons").
However, this leads me back to my old question: Can I build a RSG
that is in sync with the mains, but has a higher break rate? I do NOT
mean 800+ bps, nor do I mean crooked (being non sync) values like
320/384bps (50/60Hz). I mean "x" times the mains frequency, like
240(200) or 360(300) bps for 60/50Hz.  I am stuck with neons for the
time. I can understand why NSTs can die using a async RSG. By using
a "high speed" (relative) sync RSG with bps rates mentioned above, I
could get away with a smaller cap. The MRC (mains reso cap) for my
final setup would be around 254nF (for 4500VA). That is way too big.
Using a sync RSG that fires 2 per half cycle (instead of once) I could
half my needed cap size. As static gap (more or less) fire at will and
have break rates higher than 2*Fmains, I canīt see any reason why
a sync RSG wouldnīt work. The stress shouldnīt be any larger than
using a static gap and the higher number of break rates should help
protect the cap from overvolting, because it has the possibilty to
discharge more often. It would seem such a setup would be much
safer for the xformer and cap than a resonant charged and 100/120
bps discharged setup. Of course, SSGs (safety spark gaps) should
still be incorperated. So, can I do this and will it be safe for my NSTs
and caps?!? Any ideas and comments are welcome.

Pondering in germany,
Reinhard