Subject: Re: MMCs
From: Terry Fritz <twftesla-at-uswest-dot-net>
Date: Mon, 05 Jul 1999 18:42:29 -0600
You want caps with really low dissipation too. the 448 series is .1%
while the 428 series is .15% In my quick look, I think the 448 series
would be better.
I would worry some about running just one string. All the primary current
is usually divided up between many strings of caps. A single string my
overheat and fail but it depends on you system...
EVOX is a common substitute for WIMA caps so no problem there. I was VERY
impressed with the great data sheets they have. They specifically list
thermal dissipation for each part!
BTW - I sent this original post out twice. It was a goof on my part and
not the dual post problem. :-)
At 04:23 PM 7/5/99 -0400, you wrote:
>I got a RIFA catalog at work and was just browsing through it looking for
>the best caps to buy for my small tesla coil. I naturally went to the pulse
>cap section and picked out the PHE428TR6120J found on page 186. They are
>.12uF rated at 1000VAC. The max dU/dt rating is 800. I figure I can put 10
>in series and get .012uf rated at10,000 VAC.
>I was planning on using this with a 7500V -at- 30mA NST.
>I also noticed these other capacitors listed as power capacitors. The info
>is shown on page 206. These look ideal for TC use. They have a much higher
>dU/dt rating than the pulse caps, can handle high currents and have a very
>low loss rating. The problem is that they look very expensive although I do
>not have a price list so I don't really know. I have never seen anyone
>mention these on the list. Does anyone have any experience with these? Are
>they as good as I think they look, or should I go with the pulse caps that I
>If anyone is interested their website is www.evox-rifa-dot-com.