Re: 10KV RMS -at- 300MA for less than $100

To: tesla-at-poodle.pupman-dot-com
Subject: Re: 10KV RMS -at- 300MA for less than $100
From: Tesla List <tesla-at-stic-dot-net>
Date: Sun, 16 Mar 1997 21:13:57 -0600
Approved: tesla-at-stic-dot-net
Subject: 
        Re: 10KV RMS -at- 300MA for less than $100
  Date: 
        Sat, 15 Mar 1997 09:23:34 -0500
  From: 
        Steve Falco <sfalco-at-worldnet.att-dot-net>
    To: 
        tesla-at-pupman-dot-com


> Those transformers may not be suitable as TC power supplies. It
> appears that they may be ferro resonant transformers and even more
> fragile than neons.
> I was tempted to get a couple myself but I'm waiting until
> someone actually reports results.
> The verdict is still out on these. Since you already ordered 2 of them
> report back to us what results you get. (even if bad)

I ordered four of these transformers.  One had quick-disconnect
terminals and the other three were the "directly connected wire" type. 
I hooked them up as stated on the instruction sheet, with the provided
capacitor to resonate the iron core.

I wired the secondaries in series and the primaries in parallel to get
10kv out with 120v in.  I found that I had to tighten up my spark gaps
considerably to get the coil to fire  (I had been using a 12kv neon). 
The spark gaps had a much greener look from the vaporizing copper
because of the increased current drawn.  I suspect the gaps would not
last very long with 3 KW of power applied!

The spark output was down considerably from my 12kv 30ma neon presumably
because of the lower voltage and because the spark gaps were overloaded
badly.  A much bigger main capacitor might have helped soak up the extra
current available.

Sadly, the transformers only ran for a few seconds, then I saw smoke. 
Turned out the transformer with the quick-disconnect terminals arced
over between one of the high voltage terminals and the secondary
windings.  I'm afraid this transformer is totalled, because the paper
insulation between the secondary layers charred away.  I was using
protective spark gaps and air-wound choke coils, so these things are
pretty sensitive.

I'm not sure if I should send back the two transformers I have not
touched yet or keep them.  At a few seconds of operation per
transformer, they are pretty expensive.  If they can be made to hold
together they would be fantastic... but I'm not sure I want to submerge
them in oil, which seems the best solution.

        Steve Falco
        sfalco-at-worldnet.att-dot-net