RE: Capacitance

["Dale Hall" <Dale.Hall-at-xxxxxxx> (by way of Terry Fritz <twftesla-at-xxxxxxxxxx>)]

The Primary capacitor serves to isolate 
the current limiting inductance of the power source & wiring 
to provide higher achievable peak discharge current 
than otherwise could be obtained.

A Cap is a "buffer" of sorts. 
  accepting charge from a wimpy (could be any waveform) 
  source of average current over a longer time 
 (mS, seconds, minutes, even hours: limited by Cap leakage) 
  to make available, a very high peak current,
  delivering it in microsecond time frame.
  The load current limit is then dominated by the 
   Load circuit impedance of the Pri,
      (rather than impedance inherent in the power source & wiring)
    coupled Sec and its load (corona & sparks).
    Loads reflect back to the Pri, more load = higher equivalent Rpri

A quality factor for "pulse" rated Cap is ability to deliver the 
stored charge more quickly as a function of having lower internal impedance 
(Rlead+inductance+good dielectric).

Having the quality of fast discharge also gives it the 
quality of fast charge, desirable for higher bangs/sec.

Such quality demands minimizing internal losses which minimize self heating
as well.
There is no free ride, 
these features cost more until demand & quantity production counters even that.

Regards, Dale

-----Original Message-----
From: Tesla list [mailto:tesla-at-pupman-dot-com]
Sent: Thursday, November 16, 2000 7:11 AM
To: tesla-at-pupman-dot-com
Subject: Re: Capacitance


Original poster: Terry Fritz <twftesla-at-uswest-dot-net>

Hi,

	Capacitors either store energy, as in the primary capacitor, over time and
then suddenly release it all in a big bang.  Or, they can act like filters
that try to keep the voltage at a stable value and clamp spikes.

Cheers,

	Terry

At 09:00 AM 11/16/2000 -0500, you wrote:
>Hello,
>
>Why do you need to place any capacitance across the circuit at all?
>
>Is it to eliminate voltage spikes or in-rush currents?
>
>thanks
>