Re: Strike Rail Yes? No?

[Terry Fritz <twftesla-at-uswest-dot-net>]

Hi Finn,

	That's the kind of experiment I like!!  High risk, but you get your answer!

	Although I hate to generalize to every coil setup, strike rails on coils
with safety gaps and MMCs, should not be needed.  The safety gap at:

http://users.better-dot-org/tfritz/NSTFilt.jpg

is designed to handle direct strike faults.  I did a lot of fault analysis
and it is very hard to blow MMC caps with direct arcs.  Although, I did not
hit it center strings :-))  The NST will need some protection in some cases
since the main gap may have opened leaving the windings to take the hit
which they may not like.  Although arcs have high voltage, they have very
limited energy.

Cheers,

	Terry

At 11:06 AM 7/28/00 +0200, you wrote:
>Greg!, all:
>
>This was discussed by Terry and Malcolm earlier this year, and to
>confirm the outcome of the discussion to myself, I tried to discharge
>the coil directly to the caps, photo of this daring experiment is here:
>
>http://home5.inet.tele.dk/f-hammer/caparc.jpg
>
>This was posted 10-05-2000 under the subject Rubar, should have been
>Roo-bar (did I get it right this time, Mark?)
>
>Basically, since the energy from the topload to the cap already
>originates from the same cap, with losses subtracted, it can never
>charge the cap to a higher potential than it was before, so it should be
>safe.
>
>EE types can figure this out in their minds, I had to see it to beleive
>it.
>
>Cheers, Finn Hammer
>
>Tesla list wrote:
>> 
>> Original poster: "Gregory R. Hunter" <ghunter-at-accucomm-dot-net>
>> 
>> Fellow Coilers,
>> 
>> What's the latest wisdom on strike rails?  Are they needed or not?  I'm
>> asking because I have just begun work on my all new 6" x 30" Tesla coil,
>> and I'm trying to decide if I need a strike rail or not.  I remember some
>> postings awhile back suggesting that strike rails were old hat and no
>> longer required.  This will be a "generic" coil of conventional design for
>> use with various power supplies ranging from 1600VA of NSTs on up to 4 or
>> 5KVA of pole xfmer input.
>> 
>> Best Regards,
>> 
>> Greg Hunter
>> www.angelfire-dot-com/ga3/tesla
>