PIRANHA Update

Terry Fritz, Tue Feb 13 2007, 10:05PM

Update:

I updated the site and had to break most of the links in this post in the process Hopefully the information will now be found here:



Contact me if you need more info till I get it all back together.

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Hi,

I wrote up this update about the PIRANHA for a guy that wanted to make a little one and just thought I would mention it here too...

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SISG's and PIRANHA class coils can run at any power level depending on the number of SISG sections used. It is about 6 inches of arc multiplied by the number of sections minus the toroid radius. So one of Mark's SISG boards would be fine for say an 18 inch arc coil. You would need a small variac or one of the solid state variac boards Dr. R. mentions for control. The basics of the SISG are here:



I never got further on "my" solid state variac thing. I "think" DC's needs a charging choke where mine would not.

Most of the details are here:



There are actually "three" versions of the PIRANHA.

PIRANHA-I was the first demonstration coil:











It used a modified prototype 3 sections SISG experimental board:





It's a cool coil, but the giant resistor in it waists way too much power. Although it demonstrated and served as a prototype of the concepts, the PIRANHA-I electrical design is really very obsolete and I don't recommend it. The physical coil is fine. If it was not for historical value, I would replace the electronics with PIRANHA-II


PIRANHA-II uses the full PIRANHA charging system for very high efficiency and is what you want to use:













You would just change it to use "one" of Mark's boards and it would use a lower input voltage and current. All the component values are the same but the caps probably don't need very high current ratings for just one board. With its ball terminal toroid (which works fine*) and PIRANHA-II electronics, it is probably one of the most advanced Tesla coils on Earth (although the vastly more complex DRSSTCs have more technology and "stuff", they don't work as well Finn's triggered single brick BRISG is a "stunningly" wonderful machine too!!

*Dave has made the biggest sparks off a ball terminal with his coil:




PIRANHA-III is a dual MOT 120VAC 20 AMP (single circuit :p ) coil that would put out 8 foot arcs. Although designed, it has not been built yet. PIRANHA-II scares me bad enough at "1/2 power" already =:O)


Microwave parts can be bought new and at a great price from this place if you don't want to shop at the junk yard:



The higher wattage MOTs are best since they do not have as much loss and are fairly cheap at $55 to $65. Those 16kV 750mA AMI3347 diodes RULE!!


Note that PIRANHA primary drive circuits are EXTREMELY dangerous!!! There is "NO current limiting on the HV"!! Ballasting is done by "magic"*. Even pig systems are probably safer!! PIRANHA-II's primary circuits are totally enclosed and double insulated. It does not need cooling vents since it does not waist power.

*I was hoping Conner would figure it out :O)) But only the computer seems to know...

Cheers,

Terry