TSSP: List Archives

From: "Terrell W. Fritz"
Date: Mon, 14 Oct 2002 21:02:55 -0600
Subject: Re: [TSSP] Top Voltage

Hi Boris,

At 08:04 AM 10/14/2002 -0700, you wrote:
>
>Hi All,
>I have already stressed couple of things regarding
>brekout tresholds of TCs.
>I don't know the reason why but appears nobody except
>Paul pays attention.
>Please,don't get me wrong becouse of it but I have to
>say:None are so blind  as those who will not see.
>Therefore,I find useful to repeat them one more time
>and once for all: 

Forgive if I am to blame for any of that.  Sometimes things take awhile to set
in my brain.  It seems to be  getting worse with age but I have always been a
bit dense :o))

>Classical disruptively run TC effects to inital
>discharge processes differ from case to case and are
>affected more or less by 5 possible factors.These
>would/might be:
>a)Coupling and frequency 
>b)BPS rate
>c)Shape and size of electrode
>d)Quenching 
>e)Atmosphere conditions
>
>Regarding c ,an old dusty book I have offers the
>following empirical formula for min. E field necessary
>for corona ignition of spherical electrode (placed in
>a long gap):
> 
>Emin~28A(1 + 0.54/SQRT(Axr))
>
>where 
>r..radius of spherical electrode 
>A..coefficient for atmosphere conditions(=1 for
>standard conditions)
>Emin..minimum E field for corona ignition 
>
>Hence ,according to that one ,the breakout treshold
>field for Terry's OLTC setup could be as high as
>40kV/cm.   

Yes!  I finally feel we do understand this breakout thing far better that I
thought.  Sometimes sitting there with cables, scopes, sparks, and so much
other stuff going on, one just does not see the "answer", but only the "data". 
It really help having people looking over my shoulders that are free to ponder
just the results and not worrying with finding scope probes and power strips.

>
>Another thing.I urge Terry to investigate other listed
>things as far as he can with present OLTC arrangment.

Ok.

>Also,some CW tests vs brekout treshold would be
>welcome.I know it is much to ask,but currently you are
>the only one to do it in most controlable fashion.

What do you mean by "CW"?  Is this the normal 360BPS mode or do you mean run
the coil from a true high power sine generator (I don't have one).  Running the
coil normally is pretty easy but I think I will put foil on the ceiling.  I am
just not sure what is up there but there must me AC wiring and other unknowns
that foil would isolate.

Cheers,

        Terry

>
>Best regards,
>Boris  
>
>_


Maintainer Paul Nicholson, paul@abelian.demon.co.uk.