RE: A search for a better primary

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: "Jim Mora" <jmora@xxxxxxxxxxx>

Hi Gerry,

Please keep me in the loop on your excellent simulations. Once again we find
our selves building very similar coils. Mine will be 12"x 60+ 18 awg mag
wire. My PrCap will be mmc at .1 made of 12 strings of (18) 942c .15uf -
Primary .5" spaced .5" pancake. Have you done any simulations with solenoid
primaries? As you pointed out I will be close to Resonance but will be
running asrg >200 bps for starters.. 3 phase is near on the horizon. I also
will be using a 14400V 5KVA pole chicken.

Jim Mora.
Thanks for your excellent graphs.

-----Original Message-----
From: Tesla list [mailto:tesla@xxxxxxxxxx]
Sent: Monday, September 11, 2006 9:01 AM
To: tesla@xxxxxxxxxx
Subject: Re: A search for a better primary

Original poster: "Gerry  Reynolds" <gerryreynolds@xxxxxxxxxxxxx>

Hi David,

I will be doing a similar analysis on a 12x60 inch coil being driven
by a 5KVA PIG.  I will be glad to report on that analysis and its
corresponding coupling coefficients.  As for a misfiring SG,  I can
believe this.  It is clearly seen in simulations where a misfire
results in the energy in the primary ringing up to a larger value and
allows a higher than normal stress level when the next bang
occurs.  Also, on my SRSG system, misfires have led to ferroresonce
where the power source starts to saturate and its effective current
limiting inductance goes down.  This can lead to resonate charging
even though you used a LTR cap value.

Gerry R.

>Original poster: DRIEBEN@xxxxxxxxxxxxxxx
>Hey guys,
>
> >From what I've gathered, it seems that the larger
>high powered coiled require looser pri/sec coupling
>than do their smaller NST powered counterparts to
>prevent the racing sparks. Also, I've noticed that
>if the SG starts improperly quenching (misfiring
>and/or running "choppy") that this can also cause
>racing sparks on an otherwise well built and well
>tuned coil system.
>
>David Rieben
>
>----- Original Message -----
>From: Tesla list <tesla@xxxxxxxxxx>
>Date: Monday, September 11, 2006 0:21 am
>Subject: Re: A search for a better primary
>To: tesla@xxxxxxxxxx
>
> > Original poster: "Gerry  Reynolds" <gerryreynolds@xxxxxxxxxxxxx>
> >
> > Hi Jim,
> >
> > Sounds like you have great performance with your 15K/120ma static
> > gap
> > setup. My 8 inch coil is running with the same power source but
> > with
> > a SRSG.  I think the trick to increasing coupling without racing
> > arcs
> > is to not couple as much into the lower turns by increasing the
> > clearance between the inner turn of the primary and the
> > secondary.  You seem to experiencing the same benifit with your 2
> > inch clearance.  Maybe you can even raise the primary (or lower
> > the
> > secondary) somewhat.
> >
> > Gerry R
> >
> > >Original poster: "Jim Mora" <jmora@xxxxxxxxxxx>
> > >
> > >Hi Gerry,
> > >
> > >My 8" 35.5" was one inch above a 15 degree 1/4" primary tapped
> > near 15. Cap
> > >was 1.5 ltr. I was running a RQ heavily blown gap that roared
> > healthily when
> > >it was up to voltage. The top hat was a 32"x8" with a 4"x12"
> > lower dryer
> > >duck siliconed to the big toriod which added much strength and
> > additional>shielding. It was powered by two Transco 15/60 HP with
> > a Terry filter and
> > >safeties all carefully adjusted with HV - tuned with a freq gen,
> > scope, and
> > >freq counter. I always cranked it to 140v+ and the sparks did
> > fly. It would
> > >consistently strike a 6 foot target; and, without a breakout or
> > target>flared chaotically outward, impressive, and very loud.
> > >
> > >My point is I used a 2" arc space (12" first turn) clearance and
> > never had a
> > >racing arc yet K was well in good range.
> > >
> > >Jim Mora
> > >
> > >  P.S.
> > >
> > >Not many agree, but I believe the larger primary couples and
> > rings higher
> > >into the secondary coil reducing the very high currents at the
> > base and
> > >eases the quench which most agree on.
> > >
> > >In the interim (until the 12" is finished), I'm going to use this
> > coil with
> > >my pig and a 1/2" flat primary with as much arc space I can get
> > and still
> > >have a reasonable k factor. While being aware that I'll be near
> > resonance>charging, as you pointed out - THANKS, I therefore will
> > keep the break rates
> > > >200 to prevent over-volting my new, tedious MMC. Having said
> > that, I have >a
> > >couple of construction easing ideas to share latter.
> > >
> > >
> > >
> > >-----Original Message-----
> > >From: Tesla list [mailto:tesla@xxxxxxxxxx]
> > >Sent: Saturday, September 09, 2006 9:58 PM
> > >To: tesla@xxxxxxxxxx
> > >Subject: A search for a better primary
> > >
> > >Original poster: "Gerry  Reynolds" <gerryreynolds@xxxxxxxxxxxxx>
> > >
> > >Hi All,
> > >
> > >I just finished part 3 of this exercise that makes an in depth
> > >comparison between an "existing" primary located 1 inch below the
> > >bottom turn of the secondary that has a 1 inch space from the 8 inch
> > >coil form and a "new" primary design that is located 1 inch above
>the
> > >bottom secondary turn but with a 3.5 inch clearance from the same
> > >coil form.  The existing primary has demonstrated a tendency for
> > >racing arcs that prompted this search.
> > >
> > >Part 2 showed a simulation method that not only seems to predict the
> > >high stress levels needed for racing arcs, but also predicts where
> > >they would breakout.  The prediction agrees with observation.  The
> > >simulation, as shown in part 3, also shows what happens when the TC
> > >is out of tune.
> > >
> > >In part 3, it is shown that even though the new primary has a
>greater
> > >overall coupling,  it also has less stress on the coil reducing the
> > >tendency for racing arcs, and also shows greater tolerance for
> > >mistuning.  If this approach works out, this may be a way to avoid
> > >racing arcs and yet get higher coupling and higher topload
> > >voltage.  This may also be a way to improve the energy rise time at
> > >the top load and facilitate better streamer formation.  The
>following
> > >are the links to the most recent of each of 3 parts.  Please read
>the
> > >papers and comment.
> > >
> > ><<http://hot->
>streamer.com/temp/GerryReynolds/In_Search_for_a_Better_Primary1.>http:/
>/hot-streamer.com/temp/GerryReynolds/In_Search_for_a_Better_Primary1.
> > >pdf>http://hot-
> > streamer.com/temp/GerryReynolds/In_Search_for_a_Better_Primar>y1.pdf
> > >
> > >http://hot-
> > streamer.com/temp/GerryReynolds/A_Search_for_a_Better_Primary2.pd>f
> > >
> > ><<http://hot->
>streamer.com/temp/GerryReynolds/A_Search_for_a_Better_Primary3.p>http:/
>/hot-streamer.com/temp/GerryReynolds/A_Search_for_a_Better_Primary3.p
> > >df>http://hot-
> > streamer.com/temp/GerryReynolds/A_Search_for_a_Better_Primary3>.pdf
> > >
> > >Gerry R.
> > >
> > >
> >
> >
> >
> >
>
>