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Re: [TCML] Rotary Spark plans > 5kw Plans or wanted, Capacitor model.

Hi David,
Hi David, et al,

I was asked not to reveal the full number when I purchased these from a well
known professional when a large number of them were purchased. So... these
are 575XX which may be a custom run. The 373xx have a rep of 1000 PPS so I
expect these at least that good. The ESL ~ .02uH. It is impregnated with

It is no whimp in size and is carrying the GA label. 

You know come to think of it, I have a 3P 50 KV solid state charging unit
too. I'll have to check the documentation when I find it to see it's power
output. It certainly is continuous. It has low voltage, low current control,
interface, so I made a simple remote controller with a meter that goes up to
50KV and simple Led on and a Potentiometer. It worked as advertised with
208v wye in. I have not tested in under load though. It was for sale for
awhile ago. Its rack mount several U's and big and heavy!

Jim Mora

-----Original Message-----
From: tesla-bounces@xxxxxxxxxx [mailto:tesla-bounces@xxxxxxxxxx] On Behalf
Of David Rieben
Sent: Tuesday, June 03, 2014 7:20 AM
To: Tesla Coil Mailing List
Subject: Re: [TCML] Rotary Spark plans > 5kw Plans or wanted

Hi Jim,

Good to hear you're still actively doing some man-sized coiling :-)  I was
wanting to ask you about your GA pulse caps. Are they the high pps rated
type (I think the 37xxx and possibly the 35xxx series as well are typically
the higher pps rated ones of the GA/Maxwell product line)? I have found that
the Maxwell 0.1 uFd, 75 kV rated one that is of the typical 31xxx (393?) low
pps rated (1 pps) works excellently in my big coil and has never shown
significant warmth above ambient temp that could be felt externally, even
after extended high powered runs. And even though my cap was used when I
obtained it, the sweet thing about it is that I have 3 identical spare units
(ebay) :-)  Although they are rated for low pps, the 75 kV rating does offer
a higher ceiling and since my transformer is 14.4 kV, I don't think I should
have to worry too much about "bumping" that ceiling, since the general rule
of thumb says the primary cap rating should be at least 2x (Vpk) - 16800
(assuming variac set f
 or max 280v input to 14.4 kV piggy) x 1.41= 23,688v x 2= 47,376 volts. So,
it would seem that a 50 kV rating on the primary cap should be sufficient
and 75 kV would just be extra insurance. However, both Cameron Prince and I
have had the same Hipotronics 0.1 uFd, 50 kV rated cap (rectangular
oil-filled metal can with a single standoff bushing terminal) to fail in our
large SG driven coils, and the failure was obviously over volt related, as
in both cases the cap had not shown signs of excessive external warmth
before the failure occurred. Also, an autopsy of my particular cap showed no
signicant burning of the dielectric inside, just a single "burn through". No
spectacular case rupture when it failed either, just the coil's output
suddenly dying and the cap's terminals showing a dead short. Also, even if a
cap is rated for just 1 pps at its rated voltage, keeping the operating
voltage at less than say 50% of the nameplate rated voltage is supposed to
increase the cap's shot  life ex
 pectancy exponencially. Not sure what the deal was with the Hipotronics
caps, though, as I had obtained both of the caps in question "unused" from
Jeff Parisse of KVA Effects. He had mentioned that he was looking to
"upgrade" his caps, though. From mine and Cameron's personal experience with
these units (maybe 2 hours of run time before failure?), I'm thinking Jeff's
"upgrade" may have been for a good reason. 

Has anyone else had any experience with these Hipotronics capacitor units?
Sorry, I can't recall any part number and I'm not sure that they even had a
part number on the label and were probably custom built units.

David Rieben


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