RE: Triggered gap questions

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

Original poster: "Ted Rosenberg by way of Terry Fritz <twftesla-at-qwest-dot-net>" <Ted.Rosenberg-at-radioshack-dot-com>

Bert: As you might be aware by now, I am on the verge of building and
installing a t-gap in my 900W coil. I have 1/8" diameter tungsten welding
rods. They will be held in robust brass posts. Above the T will be a 250 cfm
muffin fan pointed downwards and maybe an inch above the T.
I will try to shape the trigger rod to a reasonable point tonight or
tomorrow. I have a carbide and a diamond wheel which should do it.

Do you believe that I will be replacing the trigger rod often?
Guesses at this point are permitted  :))

Thanks

Ted
(guinea pig for this project)

-----Original Message-----
From: Tesla list [mailto:tesla-at-pupman-dot-com]
Sent: Wednesday, August 01, 2001 10:48 PM
To: tesla-at-pupman-dot-com
Subject: Re: Triggered gap questions


Original poster: "Bert Hickman by way of Terry Fritz <twftesla-at-qwest-dot-net>"
<bert.hickman-at-aquila-dot-net>

Marc, all,

Once the trigger pulse fires the main gap, the main discharge will flow
from one of the main electrodes, through the trigger electrode, to the
other main electrode. The trigger electrode must be robust enough to
withstand these high current discharges even though there's actually no
high current flowing into or out of the trigger electrode. Erosion of the
relatively small trigger electrode in trigatrons is a wearout mechanism.
Because of high rep rates (120 PPS or possibly more with more sophisticated
triggering circuitry in a DC system), I'd recommend using fairly robust
trigger electrodes and substantial air flow to prevent the trigger
electrode from overheating or excessively eroding...

Safe triggerin' to you!

-- Bert -- 
-- 
Bert Hickman
Stoneridge Engineering
Email:    bert.hickman-at-aquila-dot-net
Web Site: http://www.teslamania-dot-com

Tesla list wrote:
> 
> Original poster: "Metlicka Marc by way of Terry Fritz
<twftesla-at-qwest-dot-net>" <mystuffs-at-orwell-dot-net>
> 
> mike,
> this is the nice thing about the whole triggered gap situation, "design
> is WIDE open".
> one thing though, the primary tank energy doesn't go THROUGH the trigger
> electrode "per say", it tends to jump to it and then across to the other
> main electrode. maybe it does actually go through it, i don't know? i
> will have to listen to comments by those that are more knowledgeable
> because i was "AMAZED" it worked great the first attempt?
> the
> 
> Tesla list wrote:
> >
> > Original poster: "by way of Terry Fritz <twftesla-at-qwest-dot-net>"
> <Hollmike-at-aol-dot-com>
> >
> > Ok,  Here's a question for the triggered gap gurus:
> >     I have been reading this thread with much interest.  It sounds like
a
> > great alternative to the SRSG!    One thing I read is that the primary
> > current passes 'through' the trigger electrode.  My question is, could
the
> > trigger electrode be positioned slightly out of alignment with the
primary
> > gap electrodes so the triggered arc would have to take a slightly 'bent'
> > path?  This, if so, would seem to me to help alleviate heating and/or
> > corrosion of the trigger electrode.
> >    It would seem that the trigger electrode could be made into a sharp
point
> > and cause the ionization of the space between the gap electrodes to
provide
> > the conductive channel to form more easily and not actually have the
primary
> > current contact the trigger electrode at all(or very little anyway).
If the
> > trigger electrode were positioned from below the primary gap
electrodes, the
> > heat might also help 'move' the arc away from the trigger electrode.
> >  The first objection to this idea, I imagine, is that might argue that
this
> > would effectively make the gap too wide and kill a NST, but if one
placed
> > another gap or two in series, the triggered gap could have a large
percentage
> > length change, but the overall gap length would not change by much.
Having
> > the series gaps would also seem to aid quenching as well.
> > Comments?
> > Mike
> >
> >