Re: Best MMC configuration?

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Christopher Boden by way of Terry Fritz <twftesla-at-qwest-dot-net>" <chrisboden-at-hotmail-dot-com>


http://www.thegeekgroup-dot-org/Flash/Sales/MMCsales.html that page has a chart 
for layout of the caps, if you have a setup not on the chart simply email 
mbroker-at-thegeekgroup-dot-org and he'll design one for you :) Terry could also 
probably do this in his sleep.

Also. some notes passed on from Terry on MMC design...

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 (~1" 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.*

4.1 Do not place the resistors directly against the capacitors! The thin
capacitor shell may not provide good insulation. The capacitors need a good
space between them and other objects to insure they will not arc over. I
would recommend about 1/4 inch clearance between the capacitor cases and
other things.

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.

7.1 Be careful when bending the leads not to damage the connections inside
the capacitor. Tubular style caps can especially have fragile lead 
connections.

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.

* People have gotten shocked by not doing these.




Christopher "Duck" Boden Geek#1
President / C.E.O. / Alpha Geek
The Geek Group
www.thegeekgroup-dot-org
Because the Geek shall inherit the Earth!


>    Could someone tell me what would be the best setup on my MMC?  I will 
>have a
>total of 32 geekgroup caps(<mailto:.15uf-at-2000v>.15uf-at-2000v).  How many in 
>each
>string and how many strings?  I am using a MOT supply that has 2 MOT's at 
>2400v
>each with voltage doubler featured on Greg Hunter's page.