Re: DC powered Coil single phase 14.4KV 5KVA pig DCPTC ?-)

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: tesla@xxxxxxxxxxxxxxxxxxx 

> Original poster: "Dr. Resonance" <resonance@xxxxxxxxxx>
>
>
>
> The cap recharge cycle is so rapid that the movement of the spark gap
> electrodes is essentially a moot point.  All you need is adequate current

in a gap setup as SPDT and a constant DC supply of power, you can run at
almost any break rate. That's what I'm after. You need a decent sized
filter cap, but they exist.


> to
> insure the rapid recharge.  DC system not really necessary unless you are
> running 3 phase power.  A lot of extra work, time, and money with no real
> gain.

Tesla Coil projects are all about burning time and money with no real gain.

KEN

>
>
> Dr. Resonance
> ----- Original Message -----
> From: "Tesla list" <tesla@xxxxxxxxxx>
> To: <tesla@xxxxxxxxxx>
> Sent: Thursday, March 24, 2005 5:07 PM
> Subject: Re: DC powered Coil single phase 14.4KV 5KVA pig DCPTC ?-)
>
>
> Original poster: tesla@xxxxxxxxxxxxxxxxxxx
>
> This has been my approach. I like the idea of being able to fire the gap
> anytime I want, and not having to wait around for the 60Hz cycles to be
> lined up just right. Proof that this is a big deal is that people use
> synchronous spark gaps.
>
> I don't see the point to ballasting with a DC power supply either. The
> tank circuit of a tesla coil can be isolated from the power supply with
> extra contacts on a sparp gap. With this, there's no dead shorts across
> the power supply and no need to try to battle this. I've done this with an
> AC coil, but without the rectification and filtering of the power to the
> coil, there's really no point to trying to use variable break rates on
> your spark gap.
>
> I kept blowing out diodes, even with two 15kV 30mA transformers. There's
> apparently lots of ugly ringing that destroys them pretty fast.
>
> I've run out of space to work on my DC coil for the time being. I'v got
> some compensated-like recitifier stacks and a tube of fast, and fast
> avalanche rectifiers to try out. There will be lots of blue smoke fun when
> I clear some space to work in again.
>
> KEN
>
>   > Original poster: "Jim Mora" <jmora@xxxxxxxxxxx>
>   >
>   > Greeting All,
>   >
>   > I am considering building a full wave rectified and filtered DC supply
> to
>   > enjoy the perceived  luxury of have a variable speed RSG. Materials on
>   > hand:
>   > 14.4KV @ 5KVA Pig, 250 amp arc welder ballast, Powerstat (1256d
> (0-280)
>   > 7500
>   > VA max) for power up. Proposed is to wire the Powerstat between the
> mains
>   > and the series ballast. I purchased (24) stackable 7500v 1.4amp diodes
>   > from
>   > alltr. planning on stacking six per leg for the bridge. I plan to
> float
>   > the
>   > Center tap and ground the transformer. I seem to remember varying
> opinions
>   > on whether this should be done to Mains or RF ground. I have a typical
> 8"
>   > X
>   > 36" coil and numerous pulse capacitors but my present focus is on the
>   > Power
>   > Supply. I don't plan on ever running past 500ma out. Open for
> discussion
>   > are
>   > filter cokes, charging inductors, and of much concern Protection of
> the
>   > Bridge or it's robustness for that matter.
>   >
>   > I'm a signal level guy. For starters what is an appropriate filter
>   > capacitor
>   > and suggested sources and should it be preceded by a filter choke? It
>   > would
>   > seem that multiple smaller Caps would be safer then one big boomer.
> Please
>   > forward to the list if the thread would be of interest to the group.
>   >
>   > Thanks Much,
>   > Jim Mora
>   > Fillmore School District, Retired
>   > Ojai, Ca.
>   >
>   >
>   >
>
>
>