Re: Geek Caps and My calcs.

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

Original poster: "by way of Terry Fritz <twftesla-at-qwest-dot-net>" <rblaisdell-at-juno-dot-com>




> Hi Ry,
> 
> JavaMMC says the reliability is Questionable.
> The cap bank is only rated for 20kV and your talking about throwing
> slightly over this
> on the cap bank. There are other factors as well like 10 degC temp 
> rise and
> 1/2W power
> dissipation per cap. 15 caps per string would get you 30kV rating 
> and
> greatly improve
> all other variables.
> 
> You might want to use one of the MMC programs to get a reliability 
> rating
> as well as
> misc. info on your MMC design. Here is JavaMMC which is an online 
> MMC
> calculator. Also,
> there is a box just below the input boxes which gives examples. For 
> cap
> specs, the Geek
> Group 0.15uF cap is used as an example is should be convenient for 
> you.
> 
> http://www.classictesla-dot-com/java/javammc.html
> 
> Take care,
> Bart

So if Instead I use my 12kv potential tranny rated at the same 
1.5kVA 
overun on the amps a little to get 2.0kva would make the cap a little bit
more robust, 
due to the lower peak to peak voltage.

Though I ran these numbers through "javammc" and it still comes out
questionable, because the voltage rating is not double the input peak to
peak I suppose, because when I put 15caps in the number in series it goes
to say that it is excellent.

Will keeping the cap strings cooled via say a hi-flow fan or in dry-ice
make them more robust?
It seems that a cool cap is a better working cap since losses due to heat
are offset.

> Tesla list wrote:
> 
> > Original poster: "by way of Terry Fritz <twftesla-at-qwest-dot-net>"
> <rblaisdell-at-juno-dot-com>
> >
> > Can some of you read this and tell me what you think of my mmc 
> numbers.
> >
> > I will have 30 caps.
> > My power supply is a 14400 1.5kva intrument tranny.  We will run 
> it a
> > 2kva.
> >
> > So that will be:
> > 14.4kv rms
> > 20361ptp volts
> > -at- 145ma.
> >
> > 3 strings of 10 geekcaps in ||
> > for a total of .045mf -at- 20kv using the DC rating which I have been 
> told
> > is ok.
> > I am going for LTR.
> > 460bps on a rotary. Its not in sync.
> >
> > have any of ya' ll had similar setups with good results?
> >
> > Ry Blaisdell
> > Student
> 
> 
> 
>