Re: Necessity of NST Protection Filters and Safety Gaps

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

Original poster: dhmccauley-at-spacecatlighting-dot-com 


Luke,

The questions you *should* be asking are:

1.  Can I afford to lose an NST or two?

2.  Do I have the money to replace them if necessary?

3.  Am I running this NST for an important demonstration and  have backups
available?

If you answered NO to any of these questions, than a protection circuit is
definitely for you.  I don't run protection circuits in my coils, since if I
lose
an NST, i don't care either way.  I have tons of NSTs and can afford to lose
one every so often.

I would recommend using the Terry Gap which was designed by Terry Fritz.
I'm sure Terry will post the link to the specifics on this
gap to the end of this post!  (Thanks Terry!)

 >>I think you meant the Terry filter.  But here are the links to both<<

http://hot-streamer-dot-com/TeslaCoils/Misc/NSTFilt.jpg

http://hot-streamer-dot-com/TeslaCoils/Misc/terrygap.jpg

Dan


 > That's good to hear bout your NST's not burning up.  That is something I
 > will have to tackle soon.
 >
 > Do I want a protection circuit?
 > If so what is the best style and why?
 > And if so how do I choose my values for the components and why?
 >
 > If you feel like giving any input ill gladly check it out.
 > If not I may be posting some questions later after I do a little
 > reading.
 >
 >
 > Luke Galyan
 > Bluu-at-cox-dot-net
 >
 > I don't use protection networks as well on my NST powered tesla coils.
 > I
 > have 4kV/32mA, 6kV/30mA, 12kV/60mA, and a 15kV/60mA
 > NSTs which have all been used in both static gap and synch rotary spark
 > gap
 > tesla coils for hours and hours of use.  No protection networks, and
 > no protection spark gaps.  Although NST filters and safety gaps are
 > recommended, they aren't absolutely necessary.
 >
 > It is a higher risk running without them, but how much higher is hard to
 > say.  If the risk was really that high, i would really expect at least
 > one
 > of the
 > above NSTs to fail especially considering how much use they are getting.
 > For one demonstration, I ran my 15kV/60mA NST for about 8 hours
 > straight (at about 20% duty cycle - 1 minute run-time, 4 minute rest
 > period
 > waiting for next group to see exhibit).  Thats a lot of use in one
 > day!!!
 > That NST was darn hot all day!!
 >
 > I mostly use Franceformer NSTs.  I wonder is there are major differences
 > in
 > the construction of various NSTs from manufacturer to manufacturer
 > making
 > one type more prone to fail than another type.
 >
 > Dan
 >
 >
 >
 >
 >