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MMC construction tips



Hi All,

I just wanted to mention a few important tips for MMC construction...

1.	Always make the strings individually selectable so you can get many
different values of capacitance.

2.	Leave a small (~1/8")air space in between the caps in a string for air
flow and to leave room if one fails.

3.	Be sure to leave a good distance (~3/4" or more) between the strings so
if some are not used, that active strings will not arc to inactive strings.

4.	Put 1/2W 10Meg ohm (or some close value) resistors across each cap for
safety and balancing.*

5.	Be sure the resister leads are actually wrapped around the cap leads so
they will stay in place if the solder gets hot or the solder connection was
not sound.*

6.	Remember that the whole cap is at very high voltage so it needs to be
mounted away from metal and in a safe location.

7.	Perfboard, like DigiKey# V1011-ND, makes mounting the caps really easy.

8.	Do not connect the caps between strings together even though they are at
the same potential.  This defeats the cap's self healing and value
selection features.

9.	Even though the cap leads seem small, use heavy primary wiring and try
to use brass or copper connections as with any Tesla cap.  Bringing the
ends of each string to 1/4" brass bolts works well.

10.	Remember that even a small EMMC cap can be just as dangerous as many
big oil filled caps...  The resistors go a very long way in making them
safer but don't get careless.

11.	???  Others I have left out  ???

* People have gotten shocked by not doing these.

Cheers,

	Terry

BTW - I'll probably be ordering another 1000 caps since the last batch went
so fast...  ;-)))