Re: Maxwell VS. MMC capacitors

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

Original poster: dgoodfellow-at-highstream-dot-net 

Snips interspersed

 >I think you being unfair in comparing the cost of one cap that's ten times
 >bigger than it needs to be to an other cap.

When we tested the Maxwells against the CD capacitors, we were looking
primarily for the same capacitance, not the same dc voltage rating. The
Maxwells that we used are the ones that are perhaps most commonly featured
on ebay, the .03uf, 35kv (Maxwell#37667) capacitors. If we had a Maxwell
37xxx series that happened to be a .0075uf 35kv capacitor, we would have
used it instead of four .03uf capacitors. We were looking for good sparks
from a 15/30. It took 4 Maxwells in series to give us the capacitance we
were looking for. That's as scientific as it got. We got good sparks from
both capacitor banks. The 14 CD caps gave us .00714uf and ran for long
periods without getting warm. The Maxwells gave us .0075uf which also  did
not get warm  after long runs.

There was no need to build a capacitor bank from cd caps (4 strings of 70ea.
.15uf/2kv) to match the dc voltage rating to the Maxwells. I was not even
using the Geek caps in my test. Geek caps are 2kv, the CD caps I used were
rated at 1600 volts dc. 1600 x 14 =22,400vdc and we were using a 15/30 on
them. 14 capacitors divided by 15,000 volts = 1,071 VAC on each capacitor,
rated for 1600 volts DC. The CD capacitor bank has stood the test of time,
and it is a testimony to how well they are built that they didn't flat out
fail,  running so close to the edge.

 >If you factor that in the Maxwell is just $24 i.e. half the CD caps.  or
 >make the CD MMC 10x bigger then it costs $500

Do you know someone selling Maxwells for $24??
I'm not sure what you are getting at, but if you want to compare apples to
apples, I'm game....

for both capacitor banks to be dc rated at 140kv........

280 New, Unused Geek group caps at 3.00 ea.....    $840.00    Plus shipping
4 New, Unused Maxwells that list for over $600.00 each...  $2400.00  Plus
shipping


As I said before, pay more if you want to, but you will be ahead of the game
with the MMC!

The CDE cap coil run can be seen here:

http://hot-streamer-dot-com/temp/16pflex.jpg


Maxwell cap coil run can be seen here:

http://hot-streamer-dot-com/temp/maxwellcapsa.jpg


Ebay caps such as are illustrated in our simple experiment can be seen here:

http://cgi.ebay-dot-com/ws/eBayISAPI.dll?ViewItem&item=2597967164&category=4662



 >I had assumed the CD caps where cheaper than even used Maxwells. I need to
 >check out ebay again.
 >Even at twice the price you could say you know what your getting with the
 >MMC. If its bang for your buck it may be worth the risk of a ebay Max


Build it, test it, let us know what happened, that's what I did :-)


Dave Goodfellow



----- Original Message -----
From: Tesla list <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Saturday, February 28, 2004 4:46 PM
Subject: Re: Maxwell VS. MMC capacitors


 > Original poster: "Robert Jones" <alwynj48-at-earthlink-dot-net>
 >
 > Hi,
 >
 > ----- Original Message -----
 > From: "Tesla list" <tesla-at-pupman-dot-com>
 > To: <tesla-at-pupman-dot-com>
 > Sent: Saturday, February 28, 2004 9:09 AM
 > Subject: Maxwell VS. MMC capacitors
 >
 >
 >  > Original poster: dgoodfellow-at-highstream-dot-net
 >  >
 >  >
 > snip
 >
 >  >
 >  > I realize that there are 2 transformers in the picture
 >  > with the Maxwells in it, but I can assure you that only one of the
 >  > transformers was powered at the time of the photos. I think that 4
 > Maxwells
 >  > could handle the 15/30 for some time since they are rated at 35,000
volts
 >  > each, so 4 in series puts them at 140,000 volts, a factor of nearly 10
 > times
 >  > the operating voltage.
 >  > Cost of the cornell dubilier capacitor bank.......under $50.00
 >  > Cost of the Maxwell
 >  > bank..............................................$240.00 (for 4) used
off
 > ebay
 >
 > I think you being unfair in comparing the cost of one cap that's ten times
 > bigger than it needs to be to an other cap.
 > If you factor that in the Maxwell is just $24 i.e. half the CD caps.  or
 > make the CD MMC 10x bigger then it costs $500
 >
 > I had assumed the CD caps where cheaper than even used Maxwells. I need to
 > check out ebay again.
 > Even at twice the price you could say you know what your getting with the
 > MMC. If its bang for your buck it may be worth the risk of a ebay Max
 >
 > Bob
 >
 >
 >