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RE: MMC caps & Resistors

Hi Ted,

I am probably the resistor guy.  I am not sure if it was my page you saw
but I am the "instigator" of the resistor thing in MMCs.

http://www.peakpeak-dot-com/~terryf/tesla/misc/ltr/

They are 10meg 1/2 watt plain Jane resistors.  Digi-key sell them for about
$11 per thousand.  They are used across all individual MMC caps regardless
of design or other considerations (one value fits all).  

They serve two functions:

1.	They drain the caps in a few seconds adding greatly to safety.  I don't
know anyone I know has ever been shocked by an MMC cap with resistors.  If
the resistors are not there, the cap can retain its charge for weeks of not
years.  A few people that have not used them have found the omission rather
"shocking" ;-))

2.	It is very possible that over time and for a variety of reasons that
unequal voltages can build up on the caps.  In other words they could be
charge to 1000, 500, -400,30... volts instead of all the same.  The
resistors insure that all the voltages on all the caps are perfectly equal
no matter what.

We use cap strings like this at work and we found long ago that the
resistors prevent failures and do wonderful things for long term
reliability.  The two bucks is well worth it.

Cheers,

	Terry

At 07:11 AM 12/01/1999 -0600, you wrote:
>Who on the list designed a sort of MMC looking affair with lots of resistors
>between the caps????? Would that party please step forward. I have many
>questions.
>For example, why the resistors? And how do you calculate their values? The
>benefits?
>I plan to build the best MMC I can for this coil and if it means a few extra
>bucks at that point, it's worth it.
>I saw that persons photos of the array and I can't recall the URL or name.
>
>Ted
>