Re: Maxwell AC vs. DC ratings

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

Original poster: "teri mckenney" <mck-at-ezy-dot-net> 

Hey Ed,
If it ain't broke, don't fix it!!!
Bill Mck.
----- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Tuesday, April 06, 2004 1:46 PM
Subject: Re: Maxwell AC vs. DC ratings


 > Original poster: Edward Wingate <ewing7-at-rochester.rr-dot-com>
 >
 > Tesla list wrote:
 >
 >  >  > Terry,
 >  >  >
 >  >  > Commercial pulse caps aren't "fragile", they simply need to be
properly
 >  >  > speced for the intended use and then operated within those specs. I
have
 >  >  > certainly never had a commercial cap fail from "overcurrent" as your
 >  >  > recent MMC postings seemed to indicate. Actually I've had only one
 >  >  > commercial cap fail in 15 years and that was due to a manufacturing
 >  >  > defect in one section. The company built me a new one for free even
 >  >  > though the warranty period had run out!
 >  >  >
 >  >  > MMCs are OK for "playing", commercial caps are for more serious
work!
 >  >  >
 >  >  > Regards,
 >  >  >
 >  >  > Ed Wingate RATCB
 >  >  >
 >  > Hey Ed,
 >  > To be fair,if you're talking about my MMC cap failings.Please keep in
mind
 >  > that my MMC is not "properly speced for the intended use and operated
within
 >  > those specs".I'm using 3 strings of 10 of the Panasonic 1600v .056uf
caps to
 >  > run a 15/60 NST.I use a static gap with a variac turned up to 140v. In
three
 >  > years I've popped 9 caps.I don't have to get the company to build me a
new
 >  > one as I can replace a popped cap and be running again in literally 15
 >  > minutes tops.I also have 2 extra strings that I can hook up in a couple
of
 >  > minutes if I want to fix a string later.I've run this coil for 20
minutes at
 >  > a time.My coil is a hobby coil for fun that I "play around" with so for
me
 >  > it's no problem to replace a cap every once in a while.It's certainly
cheap
 >  > enough.My static gap has 6 copper sections that are adjustable so every
once
 >  > in a while I've opened 'em up and let it "goes till she
blows"-dot-commercial
 >  > caps are great, so are MMC's :o)
 >  > Bill Mck.
 >
 > Hey Bill,
 >
 > Easy... don't take it personally. To be fair, I was talking about MMC
 > failures in general. In the recent past MMCs have been touted on the
 > list as being the answer to every coilers prayers and folks were pretty
 > much told not to bother with a commercial cap, MMCs were better. Now it
 > seems like there have been about as many MMC failures as there have been
 > in the over stressed commercial cap realm. MMCs are not better, just
 > different! I wish I'd had MMCs when I was getting started.
 >
 > In the past 10 years I've popped zero commercial caps, so it's been a
 > long time since I had to have the "company" build me a new one. I
 > haven't had to take any minutes to get up and running again from a
 > failed cap. :^)
 >
 > The CP caps on my maggy have well over twenty hours of total run time
 > (actual hour meter) and the break rate on the system is from 750 to 800
 > BPS! The very same caps had seen extensive duty on several classic coils
 > before that. During the Teslathon last year I put almost two hours of
 > run time on the maggy in a single afternoon while people tried out the
 > "Cage of Death" and the only part of the system that overheated and shut
 > down was the series rotary gap cooling fan motor (which is necessary
 > only because of the safety cover over the gap).
 >
 > All that said, I can't wait to fire up the maggy for the first time this
 > year after I get the lab open and have one of the aforementioned
 > commercial caps go up in a blaze of sparks and smoke. :^) That would be
 > just my luck!
 >
 > Ed Wingate RATCB
 >
 >