RE: Mutual Inductance & K Factor

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

Original poster: "John H. Couture by way of Terry Fritz <twftesla-at-qwest-dot-net>" <couturejh-at-mgte-dot-com>


Kurt -

Thank you for the graphs. Unfortunately my computer did not print them
clearly enough to read them. However, I did see that the K Factors leveled
off flat with no gradual rise. Not sure what that means. Thank you, also,
for the info you sent me on your coil in the past. I finally found it on my
computer. Your information has helped me very much in the past.

In Bart's graphs I noticed the K Factors are marked "measured". Does that
mean you used the frequency test for the K? I have used this test and found
it to be better than the inductance test for K.

I agree the Mandk and Acmi tests are at present probably more accurate than
the JHCTES for the K Factor. However, much more test data is required to
determine the true accuracy of the programs. The JHCTES can be easily
changed to agree with new test data.

The JHCTES type programs have one very important feature that the Mandk and
Acmi programs do not have. When the Primary capacitor or Secondary top load
is changed the mutual inductance changes but the K Factor does not change.
The Mandk and Acmi programs can not show this because they do not use and
coordinate enough TC parameters. This unique K Factor behavior was not known
by coilers until I posted this information a couple years ago on the List.
Even today you need the JHCTES or Java programs to check this out. Only an
advanced coiler can explain this interesting fact about Tesla coils.

John Couture

-------------------------------------


-----Original Message-----
From: Tesla list [mailto:tesla-at-pupman-dot-com]
Sent: Tuesday, March 26, 2002 6:53 AM
To: tesla-at-pupman-dot-com
Subject: Re: Mutual Inductance & K Factor


Original poster: "Kurt Schraner by way of Terry Fritz <twftesla-at-qwest-dot-net>"
<k.schraner-at-datacomm.ch>

Hi John,

extensive K factor tests and comparison to Mark's M&K program were
perfomed in autumn 2000. The simple mutual inductance method (-at- 50Hz
AC line f) was used for the tests. Some results-graphs can be viewed
on my website:

http://home.datacomm.ch/k.schraner/bw_mk2.gif
http://home.datacomm.ch/k.schraner/bw_mk3.gif

If they were not deleted, you might find the Excel files, which I have
sent you, for the full data:

Tue, 21 Nov 2000 05:13:43 File: bw_mk.zip     <-- Excel: M&K data
Thu, 23 Nov 2000 10:11:08 File: BW_design.zip <-- Excel: coil data

The bw_mk.zip file can also be downloaded:
http://home.datacomm.ch/k.schraner/bw_mk.zip

The comparison of my- and many others's results with acmi can be had
on Bart's website:
http://www.classictesla-dot-com/sim/k.html

The comparisons are giving a lot of trust in the 2 programs (MandK and
acmi), and if good precision conditions for the experiment are not
guaranteed, I would trust more to those calculations, which are based
on sound physical principles, than to an average-quality experimental
value. It seems to me, those programs need well to be distinguished,
from empirical function-fitting formulae (to a limited range of
experimental data), as a means of prediction: the former beeing
intrinsically more reliable. They may serve, delivering a set of
pseudo-experimental data for the fit of an empirical function, the
way, Bart has provided in his great Java TC calculator.

Cheers,
         Kurt Schraner


Tesla list wrote:
>
> Original poster: "John H. Couture by way of Terry Fritz
<twftesla-at-qwest-dot-net>" <couturejh-at-mgte-dot-com>
>
> Bart -
>
> Just finished checking the K factors for Kurt Schraner's BW coil of
> 11/24/01.
> Pos = Secondary above Primary in inches.
> Mark = Mark Rzeszotarski's MandKver31 program. Thank you Mark.
>
>     Pos     Mark     Java     JHCTES
>                      (Acmi?)
>
>      0      .1609    .1552     .137
>      1      .1458    .1459     .127
>      2      .1314    .1370     .118
>      3      .1182    .1287     .111
>      4      .1061    .1207     .103
>      5      .0954    .1132     .097
>      6      .0858    .1060     .091
>
> This is a large secondary coil 15.8" dia x 70" long. It is interesting
that
> the program outputs come closer together as the coil is raised and the K
> Factors become smaller. As I said all the program outputs will be equal at
K
> = zero. We must be doing something right. (:})
>
> The data is entered in Java with password "Kurt1".
> I couldn't find if Kurt made any K Factor test using the mutual inductance
> test or the frequency test.
>
> John Couture
>