Original poster: "Barton B. Anderson" <bartb@xxxxxxxxxxxxxxxx> Hi Jim,Professional pulse caps rated for this service will last a life time if you do the math. It may come down to a cost issue. Be warned however, when a pulse cap goes, so does a lot of money. When an MMC goes, it's a small cost. From a performance perspective, both are good. So, that makes it easy (economics). I use both. On smaller coils, I use my MMC's. On larger coils, I use my professional pulse caps. I've never blown up a pulse cap, but I'm still alive, so it may happen some day. I have blown up an MMC, but it was derated too low and only 1 cap died (about $2 at the time). Thus, my reason for having a little derating on MMC's, even if it's not as highly derated as pulse caps.
Regarding MMC's in general. You have the ability to design any "value" you desire and even to modify from that value if needed. Professional pulse caps are a specific value and it is more difficult to divert from that value.
In the end, it's really up to you. Look into your crystal ball. Will you use that cap on another coil someday? Will it be designed to the same value? Do you want to have the ability to vary the capacitance? The answer to those questions may help you decide.
Take care, Bart Tesla list wrote:
Original poster: "Jim Mora" <jmora@xxxxxxxxxxx> Hello All, I have approx 300 CD .15uf caps my goal was to go to 18 strings of 22 (396 total .12 uf @ 44KV) to handle my three phase DC PS. I may have the opportunity to buy 1 or 2 new Condenser Products .1uf 45KV cap which I understand take a beating. Here's my question: I've got to wondering, how much inductance is added to the capacitor bank by building an MMC of this size? Depending on the response here, I may have these for sale. 270 .15uf mostly non RohS compliant with bleeders, ceramic beads for temperature standoffs, and 400 solder- crimp- barrel connectors for easy, positive assembly. These are new in the boxes and bags from RELL. Opinions wanted. Shall I buy a few new tips for solder iron? Or go to a commercial pulse cap(s) Jim Mora If I did sell these, I would want min quantity 100 at Rell's cost plus shipping. I'll throw in the bleeders and other stuff. DC Cox will have a large stock of these when he gets to Arizona. So we will have no excuses not to build up!