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Re: New Testing


From: 	DR.RESONANCE[SMTP:DR.RESONANCE-at-next-wave-dot-net]
Sent: 	Saturday, September 13, 1997 10:28 AM
To: 	Tesla List
Subject: 	Re: New Testing

To: Ed

I presume you are not using the coax with the shield grounded.  NEVER EVER
use a coax cable to feed a TC from a pole xmfr.  The xmfr will take the
extra 50 kv this blum line effect can generate but the caps will quickly
fail.  We learned this lesson the hard way.  I presume you are using the
coax with the shield shorted to the center and only as a conductor not a
transmission line.  This is OK, but beware using coax as a transmission
line.  Better to use what I call "big red" which is essentially 15 kv
"jumper cable" with a BIL of 100 kv.  We stock it if you need it.

DR.RESONANCE-at-next-wave-dot-net



> 
> From: 	Esondrmn-at-aol-dot-com[SMTP:Esondrmn-at-aol-dot-com]
> Sent: 	Friday, September 12, 1997 8:42 AM
> To: 	tesla-at-pupman-dot-com
> Subject: 	Re: New Testing
> 
> In a message dated 97-09-12 03:34:02 EDT, you write:
> 
> << Hi Ed,
>  
>  Sorry to hear that you are still having problems with your system.  As
>  we've discussed in private email, my system is practically identical to
>  yours.  I too am running a 6" coil with a 5kVA pig (most of the time!),
>  225amp arc welder without resistors, Superior Powerstat, rotary gap (4
gap
>  series unit Ed Wingate just built for me), and RG213 HV feed cables.  I
>  just added a pair of .05uF 50kV pulse caps in series for .025uF tank
>  capacitance...same as you.  Our systems couldn't be much more similar. 
My
>  tank circuit interconnects are a combination of heavy copper bussbar and
#1
>  welding cable.   I am not running any static gaps in series with my
rotary,
>  and the rotary fires very smoothly with the variac at only about 2/3
max.
>  At 14.4kV I would think that your .19" total gap would be fine.  Then
>  again, it couldn't hurt to just throw a jumper across those static gaps
and
>  take them out of the circuit as a test.
>  
>  Questions:
>  
>  -Are you setup with the gap or the cap across the HV lines from the pig?
>  
>  -Any chokes or bypass caps?  I seem to remember some in a photo of your
>  setup.  Have you tried taking these out to see if something is shorted?
>  
>  -How is voltage out of the variac to the pig?
>  
>  This must be frustrating, particularly after having waited so long for
that
>  CP cap to come back.   It's a puzzle indeed.
>  
>  
>  
>  Charles Brush >>
> 
> Charles,
> 
> Thanks again for the reply.  It does sound like our systems are almost
> identical.  I do envy your capacitors.  They should be bullet proof.  I
still
> worry about loosing mine again.
> 
> My HV feed lines come in and connect directly across the gap.  One side
to
> the static gap and the other side to the rotary.  The static gap and
rotary
> are connected together with no other connections at that point.
> 
> Good memory.  My filter board does have filter caps on it that were used
with
> neon transformer power supplies but are out of the circuit for the pole
pig
> supply.  About the only thing on that board is the safety gap and two
series
> chokes, about 20 turns of #12 wire on large ferrite cores.  They probably
> don't do a thing, but I leave them in the circuit.
> 
> The voltage out of the variac goes up to full line voltage.
> 
> I replaced all the contacts on the rotary gap last night, reset the
contacts
> as close as possible and reduced the two feed lines to the cap from three
> RG213 wires in parallel to two.
> 
> I am puzzled why the system won't run at all with any resistance in
parallel
> with the welder - it used to run better with that configuration.  I will
try
> it without the parallel resistance and without the static gap if
necessary.
> 
> Ed Sonderman
> 
>