RE: Ryan's Coil is Working. :)

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

Original poster: "David Dean by way of Terry Fritz <twftesla-at-uswest-dot-net>" <deano-at-corridor-dot-net>

Hi Ryan,

Glad to hear the good news. My calcs indicate a break rate in the
neighborhood of 250 or there abouts. I suspect the heating of the MOTs is
why you are not seeing any "bucking". Heating means I^2*R loss which means
resistance which means some smoothing is taking place in the MOTs
themselves.

later
deano

> -----Original Message-----
> From: Tesla list [mailto:tesla-at-pupman-dot-com]
> Sent: Saturday, February 03, 2001 2:26 PM
> To: tesla-at-pupman-dot-com
> Subject: Ryan's Coil is Working. :)
>
>
> Original poster: "Ryan Ries by way of Terry Fritz
> <twftesla-at-uswest-dot-net>" <spud-at-wf-dot-net>
>
> 	Well finally all the hard work is starting to pay off.  I'm
> using four
> MOTs in series/parallel to draw about 20 amps at 240 volts to the pig.  It
> works almost flawlessly, and I can't see any of the typical "bucking" that
> many people witness while using strictly inductive ballast.  The only
> problem is that the MOTs get VERY hot after just a very short run.  Each
> (1200w) MOT should only see about 10 amps in their current configuration,
> but they're still smoking after 20 seconds.  I'm sure it has something to
> do with them all not being the exact same power level. :-)  Two
> of them are
> 1200w, and the other two are 1000w and 1440w respectively, so those two in
> series equal about the same as the two 1200's, so it all evens out.  The
> funny thing is, that the 1000w unit is not the one that is getting the
> hottest; it's the 1200w ones.
> 	Anyway, I got some pretty massive sparks at 4.8kW.  It
> seems that pole pig
> power is much more sensitive to tuning than NST power.  I went
> from getting
> 4" sparks from the TC to getting 4' sparks just by moving the
> primary tap 1
> TURN! :)  Anyway, after all the tuning was done, I got about 6 foot
> discharges to grounded objects, and several strikes to the primary.  Not
> quite as long of discharges as we would have hoped for that power level,
> but I think it's pretty good considering the circumstances.  (poor
> capacitors, poor spark gap, etc. )  I'll have to do something
> about that...
> 	We were using an alligator clip as the adjustable tap from
> the capacitor
> bank to the primary coil.  The pole pig incenerated the clip
> after a couple
> runs.  I'll have to find something else for that too.
> 	Here's the thing that bakes my noodle all the time: Our
> capacitors.  These
> are the MMC capacitors we got off of someone on this very list; 100 pieces
> for $20.  They are .21µf -at- 600 VAC.  We have 3 strings of 18 capacitors.
> Think about that...  The MMC is severely underrated, and with pole pig
> power in Tesla coil service!!!  These babies never even get warm!  That
> boggles my mind, considering that these are probably some mediocre
> polyester caps anyway.  We've been using them in that configuration for a
> few months now, and not a single cap has even blown.  Lucky us. :)
> 	What's a good way to stop the arcing to the primary?
>
> 	-- Ryan Ries
>
> PS - Much thanks to Scot D for helping me out big time with the inductive
> ballasting!
>
>
>