Re: arcing to primary

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

Original poster: "Bunnykiller by way of Terry Fritz <teslalist-at-qwest-dot-net>" <bunikllr-at-bellsouth-dot-net>

Tesla list wrote:

>Original poster: "Lau, Gary by way of Terry Fritz <teslalist-at-qwest-dot-net>" 
><Gary.Lau-at-hp-dot-com>
>
>I'm not sure that a primary strike (or any number of them) poses any 
>threat to the tank cap.  If your tank cap starts out charged to 20kV, 
>transfers that energy to the secondary, and then following a strike 
>manages to achieve some higher voltage across the tank cap, then you've 
>_created_ energy in the process, clearly impossible, a violation of 
>conservation of energy.
>
>A greater hazard from primary strikes is common-mode voltage applied to 
>the NST secondary.  This is why safety gaps and bypass caps to ground in 
>an NST protection network are recommended.  And even with these measures, 
>common-mode noise transmitted through the NST to the mains is likely, and 
>this is why EMI line filters are recommended.
>
>Regards, Gary Lau
>MA, USA
>
>
> >Original poster: "Dr. Resonance by way of Terry Fritz 
> <teslalist-at-qwest-dot-net>" <resonance-at-jvlnet-dot-com>
> >
> >Any time you connect 400-500 kV to a primary coil that is directly
> >connected to a capacitor bank it puts excessive stress on the caps.
>It's
> >sort of like the "final straw that broke the camel's back".  It may not
> >kill them immediately but it's definitely not a good idea to allow this to
> >continue unabated.
> >
> >Support 3-4 small round brass cabinet knobs on 1/2 in. dia. x 3 in high
> >Delrin posts at the outermost edge of the upper subbase assembly.  We run
> >the ground wire connection inside the Delrin support post.  Each is
> >connected to ground and provide a rapid attachment point for stray 
> streamers.
> >
> >Dr. Resonance
>
>
interesting thought.....

what about the toroid to primary strikes that occur in medium to large ( 
okay semi large coils  12X50+ secondaries) that can produce 1MV+ 
streamers??   why dont the caps blow out at that instant????   are the 
safety gaps that impressive to ward off that differential during that uSec 
pulse of EHV???

My most impressive picture of my coil running shows a ground strike at 12' 
plus a toroid strike to primary coil but  like a Timex " it still kept on 
running..".    my caps are only rated for 200KVAC  ( 4 series at 50KV 
each)  1/5th of what was subjected to the caps during that uSec or more 
....  or do we have a situation that provides us with a different voltage 
rating to what we are accoustemed to as to what we think we are getting as 
per streamer length per voltage??    Are we getting the voltages that are 
estimated by John? or are we seeing something different due to the higher 
Hz??    Now Im confused...   Am I getting 1MV + at 12' streamers or is it 
just  150KV???

just a thought...

SD