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Re: neon PFC

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> From: Tesla List <tesla-at-poodle.pupman-dot-com>
> To: Tesla-list-subscribers-at-poodle.pupman-dot-com
> Subject: neon PFC
> Date: Wednesday, February 05, 1997 1:25 AM
> 
> Subscriber: mhammer-at-misslink-dot-net Tue Feb  4 22:38:38 1997
> Date: Tue, 04 Feb 1997 20:14:50 -0600
> From: Mike Hammer <mhammer-at-misslink-dot-net>
> To: tesla-at-pupman-dot-com
> Subject: neon PFC
> 
> 
> I have 2 12kv/60ma neons that I have unpotted and
> rebuilt. These units are internally power factor
> corrected. The value of the internal caps is rather
> small. (4 mfd)
> 
> My question is if I remove some of the magnetic
> shunts does the required value of capacitance
> for PFC change?
> 
> Also in paralleling up neons is it better to
> treat them individually or PFC them as a unit?
> 
> Mike Hammer
> mhammer-at-misslink-dot-net

Mike,
When I am building power supplies for electronics systems one of the
principals I try to follow is "keep the solution with the problem". So, for
instance, when a particular Integrated Circuit needs extra filtering or
bypassing due to the way it handles current or responds to noise on the
power line, I put the bypass or filter capacitor as close to the integrated
circuit as I can. Personally I would try to get the PFC capacitor as close
to the transformer as I could. Maybe even go so far as to fairly
permanently attach the capacitor to the primary by putting terminal lugs on
the capacitor and mount it right to the primary bolts.

If you ever pull the neon transformer off of the group, its PFC goes with
it. So the other neons are not adversely affected. Face it, we coilers mix
and match and experiment and move things all over the place in our quest
for knowledge and the perfect coil.

That is also my reasoning for placing the capacitor safety gap right on the
capacitor. If I move a cap, its safety gap goes with it.

These are, ultimately, matters of personal opinion. The circuit works OK
either way. But, personally, I will always try to "keep the solution with
the problem" unless doing so causes me major grief or costs too much to
implement.

As to the magnetic shunts, I was told by somebody else (let's shift the
blame here in case I am wrong...) that when figuring out the PFC we have to
take into account the fact that the neon transformer has these shunts. So,
by the process of mental extrapolation (or is this an example of mental
interpolation...) I would venture to say that changing the shunts would
mean changing the necessary Power Factor Correction. My informant did not
postulate as to how *much* effect each shunt has, and I am not going to
conjecture on such a thing at this time, as my credibility is already in
jeapordy due to the coil winding direction fiasco. I disavow authorship of
that post and claim that a person or persons unknown to me must have broken
into my computer system while I was sleeping and posted it with the express
purpose of making me look like a fool. He or she should be ashamed of
themselves. 

Fr. Tom McGahee 
(The priest with his foot in his mouth!) Now lemme see, if the coil is
going clockwise and I stand on my head at midnight, what are the chances
that I write a post that says that up is down! DUH! And this only a day
after my saying that a resistor capacitor circuit had no phase shift. What
I need is my own personal proofreader! But you know what is great about
this Tesla list? The mistake was caught, and people have been ribbing me
about it in a most good-natured way. Thanks for the fun, guys! Your turn
will come... :^)