Re: MMC Question.

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: "J. Aaron Holmes" <jaholmes@xxxxxxxxxxxxxxxxxx>

It makes a very big difference!!  Adding caps in
series (end-to-end in a string) causes the capacitance
to go down and the voltage rating to go up.  If the
caps are all the same, then the simplified formulas
are:

Cstring = Ccap / #ofCaps
Vstring = Vcap x #ofCaps

Since you have 16 caps rated at .15uF at 2kV each,
Option #2 works out to: .15uF / 16 = .009375uF
(9.375nF) at 2kV * 16 = 32kV.

Option #1 is more complicated.  Here, you've got two
strings in parallel.  Assuming the strings are the
same (same number of the same type of capacitor), then
the simplified formulas for the total parallel
capacitance and voltage rating are:

Ctotal = Cstring x #ofStrings
Vtotal = Vstring

In Option #1 you've got two strings of 8 caps each, so
Cstring = .15uF / 8 = .01875uF, and Vstring = 2kV * 8
= 16kV.  Now you figure the total rating by the two
most recent formulas above:  Ctotal = .01875uF * 2 =
.0375uF, and Vtotal = 16kV (same as Vstring).

So, to recap (pun intended):

Option 1 rating:  .0375uF at 16kV
Option 2 rating:  .009375uF at 32kV

...again, very different!!

I'm guessing you're probably after Option #1 in this
case, but I could be wrong.  There are also other
advantages to the more parallel approach (Option #1),
such as better handling of high currents and thereby
less heating of the individual caps.

Curiously, what kind of transformer, power level, and
spark gap are you planning to run with this?

Best regards,
Aaron, N7OE

--- Tesla list <tesla@xxxxxxxxxx> wrote:

> Original poster: "Glen McGowan"
> <glen.mcgowan@xxxxxxxxx>
>
> Just received my new shiny bag of caps that Dr.
> Resonance kindly
> provided. I got my fancy polycarbonate MMC perfboard
> fabricated. But
> now that I got to thinking; what would be the best
> way to wire them
> up? Option #1, would it matter if  I terminated
> *both* strings to the
> same two pieces of metal at each end of the MMC? Or
> should I go with
> Option #2 and keep them all in a strict series?
> Wouldn't it still
> perform the same function in either scenario?
> Forgive the newbie
> question I'm sure this is basic electronics.
>
>
>
<http://www.cyplexia.com/IM000525.JPG>http://www.cyplexia.com/IM000525.JPG
>
>
> Option #1
>
>          |                                   |
>           |-----||--||--||--||--||--||--||--||----|
>           |                                   |
> --IN----|
> |---------- OUT --->
>           |                                   |
>           |-----||--||--||--||--||--||--||--||----|
>           |                                   |
>           |                                   |
>           ^                                  ^
>           Aluminium Strip            Aluminium Strip
>
>
>
>
> Option #2
>
>      |
>
> |-----||--||--||--||--||--||--||--||--------------
> OUT --->
>      |
>      |
>      |
>
>
|-----||--||--||--||--||--||--||--||---------------IN-----
>      |
>      |
>      ^
>      Aluminium Strip
>
>
>
>
>
> -Glen
>
>
>
>
>
>
>
>
>