RE: Primary Strikes, how serious/bad?

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

Original poster: "Yurtle Turtle by way of Terry Fritz <twftesla-at-qwest-dot-net>" <yurtle_t-at-yahoo-dot-com>

I'm still on the wrong side of the learning curve to
offer any reasons for this, but one of my mmc bleed
resistors gave up it's smoke DURING a primary strike.
As to the reasons...

I admit to having used a cheaper resister than I
should have. I was running 7 strings of 14, with a
14.4/25kVA at around 5 kVA.

I know for a fact that with my small coil, at higher
powers, once an arc reaches the primary, it rarely
lets go. This requires me to either momentarily turn
off the power, or to let it rip. I found out the hard
way that letting it go for a while, can ruin your
primary supports.

See:
http://www.geocities-dot-com/yurtle_t/tesla/disasters.htm

Of course, if I had had a strike ring, it's supports
would be just as vulnerable, and I'm sure a strike to
a grounded ring would NEVER let go.

Adam


--- Tesla list <tesla-at-pupman-dot-com> wrote:
> Original poster: "Lau, Gary by way of Terry Fritz
> <twftesla-at-qwest-dot-net>" <Gary.Lau-at-compaq-dot-com>
> 
> I'd like to refute the suggestion that a primary
> strike could damage a tank
> cap.  I believe this is impossible.  The only way
> the cap could be damaged
> is if it were charged to too high a voltage.  No
> matter how or when a
> streamer strikes the primary, the tank cap cannot be
> charged to a voltage
> higher that what existed before the spark gap fires.
> 
> I personally haven't yet made up my mind as to
> whether a strike ring is
> needed.  The down side of using it is that being the
> highest grounded point,
> it attracts streamers.  But yet it may provide cheap
> insurance against some
> other failure modes.  Possibilities include NST
> damage, and transients
> coupled into your AC power lines.
> 
> Gary Lau
> MA, USA
> 
> 
> 
> Original poster: "brian by way of Terry Fritz
> <twftesla-at-qwest-dot-net>"
> <ka1bbg1-at-mcttelecom-dot-com>
> 
> Hi, sounds like its time to get a piece of 3/8
> copper and make a strike
> ring! and yes it will destroy your caps and NST
> easily! cul brian f.
> 
> ----- Original Message -----
> From: "Tesla list" <tesla-at-pupman-dot-com>
> To: <tesla-at-pupman-dot-com>
> Sent: Thursday, July 19, 2001 7:56 PM
> Subject: Primary Strikes, how serious/bad?
> 
> 
> > Original poster: "jpeakall by way of Terry Fritz
> <twftesla-at-qwest-dot-net>"
> <jpeakall-at-mcn-dot-org>
> >
> > Howdy All,
> >
> > Finally built a bigger torrid and got it tuned
> right. However, the
> increased
> > sparks are hitting parts of the primary circuit
> with fair regularity. I
> have
> > a Fritz RF filter and a carcom filter. Am I gonna
> toast my NST? Or will I
> > blow up things connected to the AC mains?
> >
> > Thanks,
> >
> > Jonathan Peakall
> >
> >
> >
> >
> 
> 
> 
> 


=====
Adam Minchey
yurtle_t-at-yahoo-dot-com
www.geocities-dot-com/yurtle_t/index.htm

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