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Re: MMC lead length and bends...



Original poster: "Steve Ward" <steve.ward@xxxxxxxxx>

Nope.

When you add stray L, you will have to slightly reduce the primary L
so that the total inductance is the same (to maintain tuning).  The
peak current is mostly controlled by the surge impedance (Z =
sqrt(L/C)).  The MMC may have more ESR than a commercial pulse cap,
but this is swamped by the spark gap losses.

Steve

On 11/7/06, Tesla list <tesla@xxxxxxxxxx> wrote:
Original poster: "C. Sibley" <a37chevy@xxxxxxxxx>

Wouldn't all of the stray inductance adversely affect the peak current?

----- Original Message ----
From: Tesla list <tesla@xxxxxxxxxx>
To: tesla@xxxxxxxxxx
Sent: Monday, November 6, 2006 6:56:45 PM
Subject: Re: MMC lead length and bends...


Original poster: "Barton B. Anderson" <bartb@xxxxxxxxxxxxxxxx>

Hi Jim,

As Jim Lux and Antonio explained, it's likely not
a big deal, but it "is" worth measuring,
especially on a large MMC as you are building.
Keep in mind that the inductance is relative. If
you have a really small coil that uses little
primary L, then the concern is greater. But if it
is a normal size coil (3" secondary or larger),
there's likely no worry's. I have found through
both modeling and experimentation, that lead
inductance is an issue when the primary is small
(for a tiny coil) and the MMC inductance may also be worth taking a look at.

I'm glad you brought this point up. It's
something I haven't measured and it was never a
concern before (until I started building little tiny coils).

Take care,
Bart

Tesla list wrote:

 >Original poster: "Jim Mora" <jmora@xxxxxxxxxxx>
 >
 >Hello Group,
 >
 >Has anyone ever taken in account the capacitor
 >lead length and bends in a LARGE mmc >300 .15uf
 >caps. If it is a non issue how are you
 >assembling the mmc short leads 3/8 spacing? I
 >was going to put a glass bead on both ends of
 >the cap, pass it through a lexan plate and
 >solder the resistor on the other side. And make
 >the connection to the next cap with a soldered
 >butt splice. The leads are making 2 right turns?
 >18 rows of 22 each string .12uf total, 44KV.
 >That is lot of tiny inductors this method, yes?
 >Furthermore, inductors in series are
 >additive-probably wholly due to the inverse
 >square law. Anyone have any ideas on this issue?
 >Or measured their MMC inductance? Iâ??ll bet its
 >a lot more then cumulative inductance of the
 >caps only. Someone please tell me Iâ??m fussing
 >over nothing; especially if itâ??s true â?º
 >
 >Best regards,
 >Jim Mora
 >
 >
 >
 >
 >