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"Enhanced" Multi Mini Capacitors

Hi All,

        I have been working for the last few weeks on "EMMC" caps.  I have been
digging through data sheets, talking to "gurus", and doing some testing.  My
goal is to find out just how hard they can be pushed and see what could be done
to improve them.

        I just want to update everyone on what I am up to.  The following cap
design is NOT proven!!!!  I don't recommend that anyone go out and make them. 
There is still testing to be done...  There are restrictions on how hard they
can be driven.  So don't blame me...

        However, testing has been going perfectly!  Fuzzy pictures are at:

http://www.peakpeak-dot-com/~terryf/tesla/misc/EMMC1.jpg
http://www.peakpeak-dot-com/~terryf/tesla/misc/EMMC2.jpg
http://www.peakpeak-dot-com/~terryf/tesla/misc/EMMC3.jpg

Here are the specs (theoretical)

Capacitance = 5.6nF +-5%
Configuration = 10 x 56nF 1600 volt metalized polypropylene capacitors
Type = Panasonic ECW-H16563JV  (Digi-Key P10516-ND)
Voltage (peak) = 22000
Current (RMS) = 3 amps  (peak)=300 amps
Burst Frequency = 50KHz to 250KHz
BPS = 120
Series Resistance = 0.11 Ohms
Drain Resistance = 100M ohm
Drain Resistor Time Constant = 0.56 Sec.
Maximum Temperature Rise = 5 C
Thermal Dissipation = 4 C/watt
Temperature Coefficient = 0.44 C/(Irms^2)
Un-Cased Dimensions = 1" x 1.2" x 5" 
Construction time = ~30 minutes
Cost = ~$22

        I ran controlled current tests through it tonight at full power using a
primary circuit without a secondary in place.  It didn't blow up! :-)  The
thermal heating was right where all the data said it should be.  I could
control and measure the RMS current going through it in the primary circuit. 
In a real coil, it should run just barely warm to the touch.  I over load the
voltage rating  but these things are pretty underrated and everyone say the
will be fine.  The capacitance didn't change even though I ran it at twice its
dissipation for about 15 minutes.  It is limited to 120BPS unless the circuit
will be designed to keep the dissipation below a watt.  However, it really has
plenty of headroom before it should blow up.

        Of course, the last two specs are the shockers! 30 minutes to build at
22 bucks!  These are going to be what my new LTR coil uses if all goes well. 
So far, they seem rock solid!  It is amazing that this little thing will do
what my much larger MMC will do.  It replaces 80 caps and has far less series
resistance.  Of course, compared to a big oil filled rolled cap, the advantage
is tremendous...

        I still need to cut caps out one by one and see where the voltage blows
them.  They really should be in some oil filled container or something.  Corona
and simply arcing across the leads is a real concern in something this small. 
Of course, they need a lot more abusive testing in a full Tesla coil system to
be sure...  

        I was wondering if we were just throwing money away with big zillion
capacitor MMCs since they were all working so well.  This cap is not wildly
over designed and has limits (as if we know the limits of our present caps
:-)), but for $22 bucks, its worth a little risk and extra design time. 
"Theoretically", they will easily last thousands of hours.  For those that have
those big (over designed?) MMCs, I think they are going to work for a very long
time ;-)

        If these EMMCs work out, the state of art in Tesla capacitors will be
"changed"!  So far, I am completely pleased with them!!!   But like I say, this
is still very "bleeding edge" stuff...

Cheers,

        Terry