Re: Dielectric constant table

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

Original poster: robert & june heidlebaugh <rheidlebaugh-at-desertgate-dot-com> 

Ken: Your capacitors must be like the ones I have. I put them on 4 pop
bottles as a stand insulator and connect them in series to reduce the total
capacitance. and they do have 1" bolt connectors.....not portable....
          Robert  H
-- 


 > From: "Tesla list" <tesla-at-pupman-dot-com>
 > Date: Sat, 20 Sep 2003 08:41:44 -0600
 > To: tesla-at-pupman-dot-com
 > Subject: Re: Dielectric constant table
 > Resent-From: tesla-at-pupman-dot-com
 > Resent-Date: Sat, 20 Sep 2003 08:51:36 -0600
 >
 > Original poster: "Crow Leader" <tesla-at-lists.symmetric-dot-net>
 >
 > ----- Original Message -----
 > From: "Tesla list" <tesla-at-pupman-dot-com>
 > To: <tesla-at-pupman-dot-com>
 > Sent: Friday, September 19, 2003 1:31 PM
 > Subject: Re: Dielectric constant table
 >
 >
 >> Original poster: Terry Fritz <teslalist-at-twfpowerelectronics-dot-com>
 >>
 >> Hi,
 >>
 >> At 10:25 AM 9/19/2003 -0600, you wrote:
 >>> Terry F: I know you think you are correct, but just to keep the board
 >>> correct. I use mmc capacitors and poly oil capacitors. Oil capacitors are
 >>> messy and large but the deliver much more current per pulse than dose the
 >>> mmc capacitors. Yes my commercial high power pulse capacitors do supply
 > even
 >>> higher current but 250 pounds each  in a bank of 3 is not very
 >>> transportable.
 >>
 >> Do your commercial pulsed caps perform better than an equal value MMC
 >> cap?  Commercial pulse caps will have high peak current ability and
 >
 > Assuming these are large can capacitors with embedded terminals, there is
 > nothing a MMC can do to touch their current rating. I doubt these these 250
 > pound cans are of tesla coil use either, they must be in the uF range at
 > 10's of kV. I have some ~260 pound caps, they are 50kV at around 7uF, pulse
 > current rating is from 150 to 400kA depending on who I ask. The high voltage
 > terminal is a 1" diameter bolt. Aerovox no longer has datasheets on my part
 > number but says they are foil, kraft paper and oil with no plastic, reason
 > being you get a higher current rating with just impregnated paper vs.
 > plastic.
 >
 >> slightly lower ESR, but that should be far far below what can be detected
 >> in a Tesla coil's performance.  If your commercial caps actually perform
 >> better, we should find out what is causing the difference.
 >>
 >>> So please don't say no one makes their own oil filled
 >>> capacitors.
 >>
 >> Ok, very few people still make oil filled caps ;-))  It would be very
 >> surprising if the oil filled caps are performing better...
 >
 > You have to define what you think performance is, and it will vary for
 > different applications. There is no universal fits all capacitor constructio
 > n.
 >
 > I have a General Atomics tesla coil-ish capacitor. The SMALLEST internal
 > connection is 2" copper ribbon. No sprayed on tinned steel lead comes close
 > to that (dry rolled poly cap). It was designed for RF and high currents from
 > the bottom up, not to be sold for $2 from a omponents distributor. It is not
 > metallized with self healing abilities, nor was it made with a high
 > probability that it will even short out during notmal use requiring self
 > healing capabilities.
 >
 > I don't have a way to measure corona yet, but I suspect this impregnated cap
 > has little to no corona compared to the little caps in AC usage.
 >
 > KEN
 >
 >