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Re: Ballast Transformers/zero X(L) at series res.
On Sun, 12 Mar 2000 22:45:54 -0700, Tesla List wrote:
> Original Poster: "Malcolm Watts" <malcolm.watts-at-wnp.ac.nz>
>
> Hi Harvey,
> Just following your argument through there seems to be
> a problem:
>
> > Original Poster: "Harvey D Norris" <Tesla4-at-excite-dot-com>
> > If the ballast contains a ferromagnetic core, it is doubtful that the
> > inductive reactance will go to zero at resonance.
Yes, thanks for pointing out this error in terminology. What I meant to
imply is that the cancelled reactances that should exist for some reason act
as a reactance is still present. That may be only one interpretation of the
observed results.My interpretation is that the materials in a core can
seriously degrade the function of that surrounding coil to resonate. On the
56 henry coils generally considered an air core coil no matter how closely
one matches the inductive and capacitive reactances, the coil can never get
better than 85% conduction that should occur at ohms law. This leads one to
wonder if the dielectric plastic spool itself, perhaps even the wooden table
the coil lays on, all delimit the coil from perfect resonance. I tend to
think that electrical texts interpretation of phase angle actually indicate
that 85% conduction actually is quite a bit more
than 15% off resonance, when in fact they may be as closely in phase as
possible; it is simply an observation that the peak of the resonance curve
does not deliver the possible Ohms Law value. Calling this a reactance
effect was probably a mistake, but how else can you describe it? Another
option might be to consider that due to the closeness of the 20,000 winds of
9 miles of 23 gauge wire to each other; the coil has a large internal
capacitance, and this does not seem to be negotiated away by the traditional
method of cancelling the reactances as used in series resonance. Also even
though water is described as being mildly paramagnetic, placing a container
of water in the coil will delimit its resonance at 60 hz
anyways.Additionally the wider separation of wires due to thicker insulation
of the 14 gauge 60 hz resonance seems that the lack of hypothesized internal
capacitance may also be an important factor in getting inductors to resonate
fully at 60 hz; something that may be easier said than done.
> The inductive reactance never goes to zero at resonance for any
> coil. A coil doesn't suddenly lose its properties because it is
> included in a resonant circuit does it?
Yes and no in my interpretation. A coil always a magnetic field with
inertial qualities, which is a measurement of its inductance. This quality
is observed by us as a time lag between cause and effect. The voltage is
causitive, the amperage which produces the volume of magnetic field is the
resultant effect. When we ask the magnetic field to move through space by
expanding and collapsing and reemerging in opposite polarity, it acts as if
it has inertia, this is the back emf of a coil, or resistance to conduction
caused by inductive reactance. A coil in series resonance has its resultant
amperage instanteously appearing from the impressed voltage, thus the
interpretation becomes that at this resonance the field acts as if it had no
inertia, and the causitive effect of this inertia, or inductive reactance
appears to vanish, but of course we understand it has only been cancelled by
the capacitive reactance.
>
> Resonance of ferromagnetic
> > coils seems to be a misnomer. The only coils I could get to truly
resonate
> > at 60 hz showing full ohms law conduction value were air coils of
> > commercially sold 14 gauge wire spools of 500 ft lengths.
> > By placing many of these in series I could contain enough resistance to
> > safely resonate them from wall voltage conditions.
> ?? Not sure what you mean. You don't want resistance in a
> resonant circuit anyway (unless its designed to have some losses)?
By using 30 of these coils in series, this gave a resistance of around 37
ohms and an inductance of .47 Henry. In this situation the coils went to
complete resonance when balanced by an opposite capacitive reactance in
series. When that happens the full ohmic value of conduction, or 120
volts/37 ohms=3.24 Amps occurs. What I mean by safely resonating is that it
then becomes imperative that the gauge of wire be able to hold this
amperage, which in this case the system was split in half, so the wires
would have to hold 6.48 Amps. This is why 14 gauge wire was used. I dont
know it is possible where the wiring could overheat in resonance, but it
seems concievable, in fact by evidence shown almost a certainty: that a
circuit could be designed to hold the amperage amount in a parallel resonant
circuit, but NOT the amount if the circuit were a series resonant one. By
interacting the
midpoints of two 180 phased series resonances we can make this situation
possible, and is viewed as a switch that when open is dual amperage
consumptions of 2 180 phased series resonances; when closed having the
amperage consumption of a tank circuit with a peculiar figure 8
configuration where the center path is shared by both the inductive and
capacitive reactive currents from opposite directions, and having twice the
recorded amperage of the side reactive currents, but also twice the
effective resistance. Thus in this scenario the 56 H coil has 1000 ohms
resistance,about 20,000 ohms inductive reactance at 60 hz,(these are round
figures)and plugging it in the wall -at-120 volt 60 hz results in 6 ma
consumption.By creating a tank circuit at 60 hz now shows a consumption of
.06 ma, but the actual 6 ma is still measured inside the circuit/ showing an
effective Q of 10. If we now take 2 of these 56 H coils and place them in
the above described figure 8 arrangement that results from placing two 180
phased series resonances at their midpoints: the amperage consumption now
shows .03 ma input, showing that half of the former amperage value due to of
reactive pathways now appearing as forwards and backards or inverted S's
coming together in this 8 shaped pathway.Q or 10 times this value = 3mais
found on the side reactances, and twice that or 6ma. across the middle path.
Now keeping this same arrangement one cannot suppose that 10 times the input
voltage can be used to produce 60 ma in the circuit, there are nonlinear
results of voltage increase anyways, but for sake of argument suppose this
were done and 1200 volts were inputed producing 60 ma across this short,
with only 30 ma on the coils. The moment that midpoint short is removed the
coils will then try to conduct 1200 volts/1000 ohms or 1.2 amps, and the
expensive 56 Henry coils may be moments from melt down of 23 gauge wire:
dont know and dont want to find out. However the fact that NST's outputs are
current limited this may be worth a try, but the point I am making here is
that such dangerous circuits are possible by interacting midpoint paths, and
also that a dual tesla primary made according to this principle has not yet
been done according to my understanding as a bipolar system. In that first
primitive scenario the arcing would exist in a gap between the two
primaries, that gap serving as the midpoint path, and each of those endpoint
connections of arcing attached to separate capacities. Again it seems that
since NST's are current limited, the approach of this design might be worth
a try for a bipolar tesla coil, I hope to try it sometime this spring.
> By then placing iron
> > cylinders in the cores I could derive a higher inductive reactance
value,
> > but when this new reactive value was balanced with a new capacitive
> > reactance value, it did not then conduct the full ohms law value at its
> > designated new parameter of resonance, as was the case with an air
core. To
> > give another example of the nonattainability
> > of ferromagnetic resonance take the typical 1.5 KVA power 440 volt
> > transformer. I measure 0.2 ohms on the primary, 2 ohms on the 440
secondary.
> > If I attempted to resonate the primary with the secondary open, by ohms
law
> > conduction that would mean 120/0.2= 600 Amps, a situation that is
easily
> > seen as impossible.
>
> The impedance of the winding is Xl, not Rdc.
I am speaking of the inverse of power factor correction, or a capacitor
across one leg of the input, as in series res.
>
> Likewise if we attempted a series resonance of a typical
> > ferromagmetic fan motor, and not the more familiar tank or parallel
resonant
> > circuit known as "power factor correction", we would find the motor
burning
> > up because the wires could not hold the amperage, if it were to even
> > approach its ohms law
> > conduction values supposedly always attained at resonance.
Ferromagnetic
> > coils cannot fully resonate because of the time lag of causitive
voltage and
> > amperage produced and limited by the rotation of the inertial iron
domains,
> > which then become less effective low loss reluctance paths at
frequencies
> > past 400 hz. For ferromagnetic transformers that might function
efficiently
> > these higher freq, and the superiority of a 4 phase system using a low
> > hysteresis loss transformer see 4 phase vs 3 phase/transformer without
> > hysteresis
> > at my messageboard under Searl machine HDN
>
> OK - so hysteresis losses become greater as frequency increases.
> No great surprise there I think. So too do eddy current losses. All
> can be lumped together and modelled as an effective series
> resistance or transformed to an effective parallel resistance.
Yes, thanks again for this description, I need to refresh my textbook
knowledge which is inadequate.
>
> Regards,
> Malcolm
> The great surprise to me is that a lossless transformer practically does
exist at higher freq. inputs, but the power input must be two phases at 90
degree phase angles, not 3 at 120 degrees. This patent description is at my
messageboard HDN
>
Binary Resonant System
http://www.insidetheweb-dot-com/mbs.cgi/mb124201
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