Re: term understanding: voltage reversal.

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

Original poster: Jim Lux <jimlux-at-earthlink-dot-net> 

At 08:02 AM 2/19/2004 -0700, you wrote:
>Original poster: "Malcolm Watts" <m.j.watts-at-massey.ac.nz>
>Hi Jim,
>
> > It is the latter... the ringing of RF
> > waveform.  http://home.earthlink-dot-net/~jimlux/hv/caplife.htm has some
> > equations from Maxwell Labs on how to scale it.  (and how to convert Q
> > to VR...)  For what it's worth, the usual TC probably has a loaded Q
> > of 5-10.
>
>In fact that would be true for a continuous output arc as in CW
>coils. For a disruptive coil, the Q is essentially the open-circuit Q
>of the secondary until ringup is almost complete. At that point the Q
>dives but even that statement needs some qualification as the loaded
>Q is still about 50% or so of the unloaded Q with air streamers
>prolonging energy trades. Scoped waveforms show this all clearly.
>High amplitude reversals are the norm for each bang under normal
>running conditions for disruptive coils, at least until near-
>completion of each initial ring-up. This BTW is why I like to design
>high Q secondaries - more volts until a discharge issues forth.

And even at Q=5-10, the VR is pretty darn high...so you might as well 
assume a VR of 100% and go from there, cap life wise.