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Re: Ok, what is an LTR cap.



Hi Terry,
           resonant charging calcs really only apply to a 
ballasted system. The faceplate rating on a pig might be 10kW 
but there is nothing to stop you drawing 100kW from it on a 
transient basis as the leakage inductance is so low (well it 
should be - it's supposed to mimic a voltage source with the 
mains behind it).

Regards,
Malcolm

On 24 Aug 00, at 20:06, Tesla list wrote:

> Original poster: Terry Fritz <twftesla-at-uswest-dot-net>
> 
> Hi Bart,
> 
> 	A 14.4kV 694mA pig should deliver 10000 watts.  If we divide 10000 watts
> by 120 BPS we get the energy per bang as 83 joules.  The peak voltage is
> 14.4 x SQRT(2) = 20.4 kV peak.  So what size cap when charge to 20.4 kV
> will hold 83 joules?
> 
> E = 1/2 x C * V^2  or  C = 2 x E / V^2
> 
> C = 0.401uF  Assuming losses eat some of that up the 0.351 number sounds
> perfectly correct.
> 
> However, pole pigs can be ballasted in all kinds of ways so you would have
> to look at the total system to be sure the the equations would apply to a
> pig system.
> 
> Cheers,
> 
> 	Terry
> 
> 
> At 06:35 PM 8/24/00 -0500, you wrote: 
> Hi Mark, Terry, 
> 
> Tesla list wrote: 
> Original poster: "Mark Broker" <broker-at-uwplatt.edu> 
> 
> > Actually, PIG's are STR's (smaller than resonant). Typically, coilers
use a 
> > 10kva, 14.4kv pig's. Resonant caps are 0.128uF (from memory). Obvisouly
> HUGE! 
> > We typically use smaller than resonant caps (STR's) on our systems. NST's 
> > however (and OBIT's), can use LTR's. Could you imagine the joules for a
pig 
> > using an LTR? I see smoke, fire, wooosh!!! Well, for most of us, not Greg, 
> > Bill, Hull, etc... or you Chris (yet?). 
> 
> Actually, Terry's MMC Calc gives me .351uF.
> For a 240/14.4kv, 694mA, 20,749 ohm pig? Terry is .351uF correct? I though
> a matching reosnant cap size should be 0.128uF. Maybe my math is wrong
> here. Someone please clarify? 
> 
> Bart 
>  Chris and I have a design, and are 
> attempting to gather enough caps (912 of Terry's, or any other combo that
will 
> work).  Did you know that there's a world-wide tantulum shortage?  I even 
> have the 
> PC board mask already laid out (I think). 
> 
> I thought that it was really 13.8kV nominal? 
> 
> Mark
> 
> 
>