Re: Secondary size

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Original poster: "Dr. Resonance" <resonance-at-jvlnet-dot-com> 


Most of my designs are planned around 1,200 to 1,400 sec turns.  This high
inductance ratio usually guarantees a spark length that exceeds the coil
length.  If you use 600-700 turns this isn't a problem but your total spark
length usually is less than coil length, at least for small to medium size
coils.  Large coils or medium coils with high power (lots of watts) produce
longer sparks with less than 12-1400 turns as they have more power to feed
the growing plasma.

Dr. Resonance

Resonance Research Corporation
E11870 Shadylane Rd.
Baraboo   WI   53913
----- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Tuesday, January 13, 2004 11:00 PM
Subject: Re: Secondary size


 > Original poster: "Dr. Resonance" <resonance-at-jvlnet-dot-com>
 >
 >
 > An optimum coil height to dia ratio is approx 4.5:1.  At values less than
 > 4.5:1 arcing to primary or strike rails occur on a regular basis.  If the
 > coil is too high the coeff. of coupling is lower and less energy is
 > transferred.
 > 4.5 : 1 seems to work very well.
 >
 > The potential output of a resonance transformer is equal to it's gain
times
 > the potential input, ie,
 >
 > Vout = Vinput peak (1.4 x Erms) x sqr (Ls/Lp)    ----    this is called
 > system gain.
 >
 > Also inductance of a coil is proportional to n^2 (high number of turns
works
 > good because of this square factor) and also to r^2 (this is the radius of
 > the coils geometry).  This r squared factor rapidly increases the
inductance
 > (Ls) in big coils so the gain (voltage multiplication factor) is high and
 > output potential is high.
 >
 > It's important to note that spark length is more of a function of current
 > (system power) than potential.  To double the spark length in most systems
 > the power has to be increased by a factor of 4 (2 ^2).
 >
 > Hope this answers your question.
 >
 > Dr. Resonance
 >
 > Resonance Research Corporation
 > E11870 Shadylane Rd.
 > Baraboo   WI   53913
 >  >
 >  > I would assume that the height would be based on anticipated arc length
 > and
 >  > the dia would simply fall into using what you can to stay in the
suggested
 >  > height to width ratio.
 >  > How do you go about deciding how tall the coil should be based on the
arc
 >  > length?
 >  > Other than aesthetics what is the method for choosing a secondary size?
 >  > What is the cut off for deciding how short a coil can be with a given
 >  > anticipated arc length?
 >  >
 >  > It seems there are coils that generate longer arcs than the coil is
 >  > high.  And since the arcs are referenced to ground it seems that is
 > putting
 >  > the top load very close to ground with respect to its output.  I know
that
 >  > the toroid slash secondary top will be at the same positive or negative
at
 >  > any one time as the arc and like charges repel so that is what keeps
the
 >  > arcs from going straight down.
 >  >
 >  >
 >  > Ok also if a height is determined what are the advantages /
disadvantages
 >  > for going with the larger diameter coil verses the smaller diameter?
Keep
 >  > in mind that when I say large or small diameter I am talking about
staying
 >  > close to the excepted rule of thumb for height to dia. ratio.
 >  >
 >  > Thanx
 >  >
 >  > I will be asking lots more questions so bare with me.  J
 >  > Luke Galyan
 >  > Bluu-at-cox-dot-net
 >  >
 >  >
 >  >
 >  >
 >
 >
 >