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Re: How could a pulse cap operate in TC?

Original poster: "Gerry  Reynolds" <gerryreynolds@xxxxxxxxxxxxx>

Every thing here looks OK with perhaps the ERS curve (1.GIF). I possibly could believe the Irms curve since if I feed the capacitance with say a 1A rms sin wave current source. The voltage across the cap will increase as the frequency is reduce. This is due to the increased XC and eventually (if the frequency is reduced too much), the voltage across the capacitance will exceed its specs. So, my question to you is what is the basis of ERS being a function of frequency and why does it go up as the frequency goes down???

Gerry R

Original poster: "father dest" <dest@xxxxxxxxxxx>

> Original poster: "Gerry Reynolds" <gerryreynolds@xxxxxxxxxxxx>

p.s.

look here:
http://hot-streamer.com/TeslaCoils/MMCInfo/other/spec_pulse_caps.pdf

quote:

"Checking the RMS current

In the past the procedure for checking RMS current
was difficult to perform accurately. Now
the process is made easy by using a new software
package called PulseCAD, available at no
charge from Evox-Rifa. After selecting a capacitor
and entering the maximum ambient temperature,
PulseCAD graphically shows the
allowed RMS current across any desired frequency
range. PulseCAD can be obtained on disk by contacting
Evox-Rifa, or downloaded directly from the
Evox-Rifa Web site: http:\\www.evox-rifa.com."

you see - "allowed RMS current across any desired =frequency="
then go here:
http://www.evox-rifa.com/europe/pulsecad.htm
and download this proggy - only 4mb.

> I believe  Steve said that the dielectric loss was insignificant at our
> frequencies.

i`m not askin about "our frequencies" - here is what i`m talkin about:

  >Original poster: Steve Conner <steve@xxxxxxxxxxxx>

 >>father dest> it`s useless to write rms rating without its frequency!

 >Not really. 10A RMS will heat a capacitor just the same whether it's
 >at 1 kHz or 500 kHz.

oh yeah? look here:

ESR (F) - http://cis.ru/~dest/1.GIF
Irms (F) - http://cis.ru/~dest/2.GIF

what now?

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