Re: ribbon vs. tubing

To: tesla-at-pupman-dot-com
Subject: Re: ribbon vs. tubing
From: Ed Harris <harris-at-parkave-dot-net>
Date: Mon, 7 Oct 1996 11:50:27 -0400

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> 
> From lod-at-pacbell-dot-net Sat Dec  7 08:43:59 1996
> Date: Fri, 06 Dec 1996 22:45:40 -0800
> From: lod-at-pacbell-dot-net
> To: tesla-at-pupman-dot-com
> Subject: Re: ribbon vs. tubing
> 
> Benson_Barry wrote:
> 
> 
> > I was thinking in terms of the proximity effect.
> > Does not greater self capacity increase the
> > proximity effect of a coil?  Thinking of it like
> > a reactance would it not increase the impedance
> > of the primary thereby limiting the di/dt attainable?
> > Barry
> 
> 
> What's the 'proximity effect'?
> 
> -GL

Both the so called "skin" effect and "proximity" effects are 
ac losses due to induced eddy currents. The skin effect is
due to eddy currents which are induced by the magnetic
field component which originates from that conductor.
In contrast, the proximity effect is the eddy current  loss 
in a conductor due to magnetic fields which originate in
other conductors.

In reality it is not always possible to seperate these two 
effects since they interact in a non-linear fashion. For 
instance, the ac resistance of a soleniodal coil is more
than the sum of the strait-wire skin effect resistance and 
the proximity effect resistances taken seperately.

-Ed Harris

[see the references I posted for more information]