Re: PIRANHA-III Power control? (fwd)

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: Gerry Reynolds <greynolds@xxxxxxxxxx>



---------- Forwarded message ----------
Date: Mon, 18 Dec 2006 23:03:25 -0500
From: BRIAN FOLEY <ka1bbg@xxxxxxxxxxx>
To: Tesla list <tesla@xxxxxxxxxx>
Subject: Re: PIRANHA-III Power control? (fwd)

Hi, just took a look at alternistors there is one rated 40 amps at 1000
volts model QK040K7 listed for $8.70 from Newark one. that is 9kw + and nice
high voltage rating run at 240 volts. there you go!
cul brian f.
----- Original Message ----- 
From: "Tesla list" <tesla@xxxxxxxxxx>
To: <tesla@xxxxxxxxxx>
Sent: Monday, December 18, 2006 7:51 PM
Subject: Re: PIRANHA-III Power control? (fwd)


> Original poster: Gerry Reynolds <greynolds@xxxxxxxxxx>
>
>
>
> ---------- Forwarded message ----------
> Date: Mon, 18 Dec 2006 16:27:29 -0700
> From: resonance <resonance@xxxxxxxxxxxx>
> To: Tesla list <tesla@xxxxxxxxxx>
> Subject: Re: PIRANHA-III Power control? (fwd)
>
>
>
>
> The biggest problem that these triac circuits have is from interference on
> the mains and interference in the triggering circuit.
>
> I'm researching the 555 with opto-isolated trigger driver that operates
off
> a rectified 12 VDC source, very similar to the cmpnet.com/chipcenter
> schematic.  I think this driver  with a 40 Amp alternistor will work, or
> perhaps we will have to use back to back 50 Amp SCRs.  Even so, I think
that
> a good RF filter should be incorporated to prevent any kickback spikes in
> the SCR circuit and I'm also advocating an 18 inch long x 2 inch ID PVC
tube
> filled with cut 1/8 inch steel rods to help clip some of the larger surge
> current peaks.
>
> Presently I'm having Matt wind up some current clipping reactors , and
> ordering some alternistors and SCRs to do some "climbing arc" MOV tests
> early in mid January.
>
> I'm really excited to see the solid state experts on the list addressing
> this problem.  Getting rid of the big, heavy, and now very expensive
variacs
> is long overdue for Tesla coil builders.  Hopefully we can all pitch
> together to solve this problem.  I think this is a very worthwhile
project.
>
> I'm leaning toward the dual SCR circuit with 555 control.  If the
> driver/control portion works well with 50 Amp SCRs and MOTs it should also
> work well with pole xmfrs, potential xmfrs, and the DRSSTC designs so we
can
> all have solid state control without the expense and weight of large
> variacs.
>
> If we can come up with a good workhorse for TC control I will do the
> schematic in MultiSim and run the board design in my Ultiboard program --- 
> then we will all have a source of PCBs to tackle this problem.
>
> I also plan on obtaining the tanks, agitators, and chemicals to run my own
> boards in batches of 10 or 20 so we will not have to rely on a PCB house
to
> run these for us.  I have plans to order this material in mid-Jan as we
need
> different types of board from time to time for various proects.
>
> Dr. Resonance
>
>
>
>
>
>
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