Re: Time constant between primary and secondary (fwd)

---------- Forwarded message ----------
Date: Thu, 18 Dec 1997 09:43:57 +1200
From: Malcolm Watts <MALCOLM-at-directorate.wnp.ac.nz>
To: Tesla List <tesla-at-pupman-dot-com>
Subject: Re: Time constant between primary and secondary (fwd)

Hi Alfred,

> Date: Wed, 17 Dec 1997 10:14:54 -0500
> From: "Alfred C. Erpel" <aerpel-at-op-dot-net>
> To: tesla-at-pupman-dot-com
> Subject: Re: Time constant between primary and secondary (fwd)
> >> Maybe I have just
> >> missed reading about this so far.  Also I would venture that there is an
> >> optimal relationship to seek between the time constants and the operating
> >> frequency (peak to peak time) so one isn't "waiting" for the other.
> >Can you be more specific?
> Malcolm,
>     If L/R (= 1 time constant = 63% of current rise)  either in the primary
> circuit or the secondary circuit, was a small enough period of time, then if
> the operating frequency of the coil were high enough, it is conceivable that
> the time it takes for 1/4  cycle of the sine wave would be less than one
> time constant, so you couldn't possibly transfer more than 63% of available
> energy (ideally it seems to me, that this time should equal 5 time
> constants).

Well the time constants are intimately associated with Fr aren't they?
You most certainly can get most of the energy across, the efficiency 
largely being governed by primary current since the gap is the 
lossiest part of the circuit and its losses climb with current (I'm 
assuming good quality caps and large enough wire are being used in 
the coils).  You can not only see this on an oscilloscope but you can 
use the peak amplitude on successive beats to calculate the energy 
loss between beats.