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Fw: SSTC does 10 foot sparks
Original poster: "John Couture" <johncouture-at-bellsouth-dot-net>
----- Original Message -----
From: "John Couture" <johncouture-at-bellsouth-dot-net>
To: <tesla-at-tesla-coil-dot-com>
Sent: Tuesday, June 22, 2004 10:38 PM
Subject: Re: SSTC does 10 foot sparks
> A copy of this post was sent to the Tesla List
>
> John -
>
> The recommendations are so simple I can list then right here. To test any
> electrical dvice you find the energy input and the energy output. This
will
> give you the overall efficiency with the equation
> Eff = energy out/energy in. Multiply this decimal by 100 and you get the
> percent efficency. If it is an electric motor the input can be measured by
a
> wattmeter and the output by a Prony brake or dynamometer. The wattmeter
will
> give you watts per second for the energy input. The Prony brake or
> dynamometer will give you a force that can be converted into energy output
> using the proper equations.
>
> You can do a similar test with Tesla coils by making some adjustments. The
> wattmeter will also give you watts per second for the energy input. As you
> no doubt know the spark output can be a problem to relate it to an energy
> output.. Because the input energy is in watt seconds you have to relate
the
> spark output to the number of sparks per second. Because the input watts
are
> a continuous per second stream (of energy) the output sparks have to be a
> continuous equal length stream (of
> energy). This type of output is subject to controversy and subject to
change
> in the future.
>
> I tested a small TC. The input was 120 watts (to get the 1 joule per 8.25
> inch spark). The output was a
> continuous number of sparks with equal length of 8.25 inches. The input
was
> from the 60 HZ utility so the number of sparks were assumed to be 120 per
> second.
>
> This produced a very interesting number.
> How do you find the energy in a single 8.25 inch spark under controlled
> spark conditions? This is the first time that this unique quantity of
> energy has ever been determined.
> The joules of energy in a single 8.25 inch spark!
> It was found like this.
> From the above test the total energy input per second / total number of
> sparks = 1 watt second input or 1 joule input per 8.25 inch spark.
> This test can be easily duplicated with any small TC.
> You can then boast to fellow coilers that you found the true energy in a
> single
> 8.25 inch or similar spark.
>
> Of course there is a lot more but this should get you started.
>
> John Couture
>
> ----------------------------------
>
> ----- Original Message -----
> From: "john cooper" <tesla-at-tesla-coil-dot-com>
> To: <johncouture-at-bellsouth-dot-net>
> Sent: Tuesday, June 22, 2004 7:53 PM
> Subject: Re: SSTC does 10 foot sparks
>
>
> > Howdy John:
> >
> > I'd really like to read the recommendations you refer to, is there a
link
> to them, book, Tesla list? Some sort of standardization seems to me a
good
> thing. I know there are many variables; break rate, temp., co-efficient
of
> coupling, humidity, barometric pressure, heck, even an approaching thunder
> storm, but anything is better than nothing and techniques can always be
> improved upon with practice. I know that most will never bother but there
> are a few of us that will always go above and beyond what amateurs would
> consider or attempt. Hey, someone has to lead by example! Sounds like
> you've an example.
> >
> > John Cooper
> > www.tesla-coil-dot-com
> >
> >
> > ---------- Original Message ----------------------------------
> > From: "Tesla list" <tesla-at-pupman-dot-com>
> > Date: Tue, 22 Jun 2004 08:29:44 -0600
> >
> > >Original poster: "John Couture" <johncouture-at-bellsouth-dot-net>
> > >
> > >John -
> > >
> > >I have made reccomendations in the past for testing Tesla coils when
they
> > >are rated in energy rather than power units. These tests leave a lot to
> be
> > >desired and would be improved by coilers over time if they were used.
> Some
> > >coilers in the past have already performed these types and found no
major
> > >problems in using them. The tests do end up with shorter spark lengths.
> > >
> > >John Couture
> > >
> > >-----------------------------------------
> > >
> > >
> > >
> > >----- Original Message -----
> > >From: "Tesla list" <tesla-at-pupman-dot-com>
> > >To: <tesla-at-pupman-dot-com>
> > >Sent: Monday, June 21, 2004 9:03 AM
> > >Subject: Re: SSTC does 10 foot sparks
> > >
> > >
> > > > Original poster: "john cooper" <tesla-at-tesla-coil-dot-com>
> > > >
> > > > Very intersting stuff, how do we agree on a baseline or procedure
for
> > > > energy in/energy out measurements? Or am I asking too much? I'd be
> most
> > > > interested in someone describing and identifying the
> equipment/measurement
> > > > techinques necessary, then we can either follow those procedures or
> 'wave
> > > > our dix in the air' claiming whatever.
> > > > John
> > > >
> > > > ---------- Original Message ----------------------------------
> > > > From: "Tesla list" <tesla-at-pupman-dot-com>
> > > > Date: Sun, 20 Jun 2004 17:03:02 -0600
> > > >
> > > > >Original poster: Sean Taylor <sstaylor-at-uiuc.edu>
> > > > >
> > > > >John,
> > > > >
> > > > >I'm sure there will be many people replying to this, so I'll keep
it
> as
> > > > >short as possible :-)
> > > > >
> > > > >>I agree you cannot "get more average power out than what is
coming
> in".
> > > > >>However, it is very possible to get much more pulse power out
than
> > >average
> > > > >>power in.
> > > > >
> > > > >I completely agree, this is the whole thing with capacitor
> discharges,
> > >you
> > > > >can charge them at a low rate, and discharge much faster to create
> high
> > > > >peak currents. This concept is used all over the place in
> technology.
> > > > >
> > > > > With Steve's TC it appears that the average power in is about
> > > > >>4800
> > > > >>watts and the pulse power out is about 300 KW giving a power gain
> of
> > >62.5 .
> > > > >
> > > > >The concept of "power gain" is a VERY misleading one. Power is
> DEFINED
> > >as
> > > > >energy transfer per unit time, so by definition when comparing two
> > >powers,
> > > > >unless otherwise stated, you are comparing a total power transfer.
> The
> > > > >difference is when you consider peak power, which is the
> instantaneous
> > >RATE
> > > > >of energy transfer.
> > > > >
> > > > >>With a potential power output of 300 KW it is obvious that a very
> > > > >>long spark would be possible depending on the TC design. That is
> why
> > >using
> > > > >>power instead of energy units is not good for rating Tesla coils.
> It
> > >can
> > > > >>exagerate the output possibilities of a coil so you have to be
very
> > >specific
> > > > >>about the input conditions.. If you use energy units you will not
> have
> > >this
> > > > >>type of problem. The energy output units will always be less than
> the
> > >input
> > > > >>units.
> > > > >
> > > > >Not necesarily true. Energy output at a chosen time (perhaps
> between
> > > > >bangs) will be much less, about 0, than the input energy. Also,
> saying
> > > > >input or output energy entails energy transfer, implying a rate,
not
> > >just a
> > > > >quantity of energy. With any sort of energy storage device,
energy
> in
> > >and
> > > > >out can be very different from each other.
> > > > >
> > > > >
> > > > >>"Peak power out will be larger than peak power in" is another
> example
> > >of the
> > > > >>confusion caused by using power with Tesla coils.
> > > > >
> > > > >I wouldn't call this a confusion so much as a difference of
> measurement
> > > > >techniques.
> > > > >
> > > > > "Peak power out"
> > > > >>cannot be
> > > > >>larger than "peak power in" unless there is a time difference
> between
> > >the
> > > > >>two
> > > > >>stated powers.
> > > > >
> > > > >Peak power out and peak power in can be very different, and either
> one
> > >can
> > > > >be greater than the other. I think what you mean by "unless there
> is a
> > > > >time difference . . . " is that the total time that the power is
> > >measured
> > > > >over is different for the input and output. You can have a single
> spike
> > >of
> > > > >power at say 10W, and measure for however long you want, and still
> only
> > > > >have a 10W peak, the time doesn't matter. I think you are
confusing
> > > > >integrating over the two times (yielding energy) rather than
> recording
> > >the
> > > > >peak power transfer.
> > > > >
> > > > > This means bringing in time into the process which gets
> > > > >>you
> > > > >>into an energy process.
> > > > >
> > > > >Not really, depending on how you use the time. Dividing by time
> will
> > >give
> > > > >an average power transferred per time, multiplying/integrating
will
> give
> > > > >you an amount of energy transferred.
> > > > >
> > > > > It would be preferable to say that "Peak power
> > > > >>out
> > > > >>will be larger than average power in". This still requires more
> > > > >>explanation. The time period involved in the output vs the time
> period
> > > > >>involved in the input. And we are back again into energy out vs
> energy
> > >in.
> > > > >
> > > > >A peak power is an instantaneous event, there is no measurement
over
> > >time
> > > > >for the peak. It happens, and it's over with, there is no amount
of
> > >time
> > > > >that matters. The time that energy is being transferred overall
may
> be
> > > > >(and will be) different between the input and output, but this is
> not a
> > > > >concern for peak power measurements, and is the whole essence of
> power
> > > > >storage devices/pulse discharges. It's why a TC works!
> > > > >
> > > > >
> > > > >>Note that when using average power that you are adding time to
the
> > >power
> > > > >>units which brings you into the energy unit solution. This has
> caused
> > >great
> > > > >>confusion for coilers in the past. Average power is actually
energy
> > >because
> > > > >>you have to use time to find the average power.
> > > > >
> > > > >Again, see above, just because you use time doesn't mean you get
> energy.
> > > > >There is a big difference between average power and energy.
Average
> > >power
> > > > >is calcualted from W/sec, over a specified period of time yielding
> Watts
> > > > >again. Energy is just a specific quantity of energy, no time
> involved
> > > > >whatsoever.
> > > > >
> > > > > In other words when you
> > > > >>connect a wattmeter to the input of a TC you are measuring many
> > >parameters
> > > > >>depending on how you want to use them. For example the wattmeter
> gives
> > >you
> > > > >>at the TC input
> > > > >>
> > > > >> 1. wattage
> > > > >> 2. average wattage
> > > > >> 3. peak wattage
> > > > >> 4. instantaneous wattage
> > > > >> 5. volt amps
> > > > >> 6. RMS wattage ??
> > > > >
> > > > >Strictly speaking, wattmeter doesn't give you all these things, it
> gives
> > > > >you one: average "wattage", or power. Some, with storage
> functions,
> > >will
> > > > >give you peak power, but this can be the peak over 1 cycle, or the
> peak
> > > > >instantaneous power. In an AC circuit, you have instantaneous
> power,
> > >which
> > > > >is defined as instantaneous current times instantaneous voltage,
but
> is
> > >not
> > > > >very meaningful in terms of what is actually going on because both
I
> and
> > >V
> > > > >are going positive and negative continuously. This is where
average
> > >power
> > > > >comes in - the average over one AC cycle.
> > > > >
> > > > >Because of non-resistive loads, the power transfer can be going in
> to or
> > > > >out of the "load", meaning the instantaneous power is positive
> > >sometimes,
> > > > >negative other times, so an average "power" is used to represent
> what
> > >work
> > > > >is actually being done - also know as the real power, measured in
> Watts.
> > > > >The RMS current and RMS voltage, considered without and phase
> difference
> > >is
> > > > >the "apparent power" - Volt-Amps, and often most devices are rated
> to a
> > > > >certain VA because the wire has to handle a certain amount of
> current,
> > >and
> > > > >it doesn't care if it's in phase with voltage or not, there is
still
> > >that
> > > > >amount of current to be passes. The imaginary power, measured in
VA
> > > > >reactive, is just the part of the current that is purely reactive,
> > > > >imaginary, or 90 degrees out of phase with the voltage that does
> > >absolutely
> > > > >no work whatsoever, and can't because the average power is zero -
> half
> > >the
> > > > >time energy is flowing into the load, the other half out of the
> load,
> > >the
> > > > >effective energy transfer is zero, and power is zero.
> > > > >
> > > > >>Correctly using all of these parameters can be very confusing.
You
> can
> > >avoid
> > > > >>all of the above confusion by properly using energy units to rate
> Tesla
> > > > >>coils. If the wattmeter is used as an energy meter you have to do
> some
> > >calcs
> > > > >>and you end up with different numbers compared to using it as a
> power
> > >meter.
> > > > >>For example a 100 watt wattmeter will give you 50, 100, 200, etc,
> watt
> > > > >>seconds when used as an energy meter if the times are 1/2, 1, 2,
> etc,
> > > > >>seconds.
> > > > >
> > > > >So how is this less confusing than using power? I can run my 1"
TC
> for
> > > > >days on end and claim that "consumed" more than 30 MJ. Then I'll
go
> run
> > >my
> > > > >15" 10 kVA pig coil for under an hour, and it'll "consume" the
same
> > >amount
> > > > >of energy. So what's the point? I can also tell you that one
coil
> has
> > >a
> > > > >bang energy of 2 J, and another 10 J. If the breakrate of the
first
> is
> > >600
> > > > >bps, and the second is 120 bps, they "consume" the same amount of
> energy
> > > > >per time, or use the same power. I can also tell you that the
> National
> > > > >Ignition Facility at LLNL consumes over 2 MJ in one shot, much
less
> than
> > > > >one second, while running my small TC will take over 5.5 hours to
> > >process
> > > > >the same amount of energy. So, how do you propose we use energy
to
> > >compare
> > > > >TCs? I'm not seeing how it would work.
> > > > >
> > > > >
> > > > >>There is a much more to comparing power vs energy and I find that
> in
> > >some of
> > > > >>my past posts I have used the words incorrectly. Coilers are
> correct
> > >when
> > > > >>they say that power and energy can muddy the waters.
> > > > >
> > > > >I think trying to compare energy and power is utterly useless. I
> think
> > >we
> > > > >can all agree that when we talk about power input, we are talking
> about
> > > > >average power, or just a rate of energy transfer into our coils.
> > >Steve's
> > > > >less than 4800 W input is the average power going into his coil,
and
> > >also
> > > > >must leave at the same rate, whether it be in the form of heat,
> light,
> > >or
> > > > >electricity. However, instead of entering at a (relatively)
> constant
> > >rate
> > > > >as happens on the 60 Hz line (since 60 Hz is slow compared to RF),
> the
> > > > >power is leaving in large pulses that happen as often as he
dictates
> by
> > >the
> > > > >breakrate of the coil, and while these peak powers occur at a
lower
> duty
> > > > >cycle than the input power has, there are much larger peak powers
> > >(maximum
> > > > >of instantaneous power) present on the output.
> > > > >
> > > > >Okay, so that wasn't as short as I expected, but I hope that
clears
> up
> > >some
> > > > >nomenclature questions for everbody (and maybe for myself, as I'll
> > >probably
> > > > >be corrected on some things I wrote).
> > > > >
> > > > >Sean Taylor
> > > > >Urbana, IL
> > > > >
> > > > >
> > > > >
> > > > >
> > > >
> > > >
> > > >
> > > >
> > > >
> > > >
> > >
> > >
> > >
> >
> >
> >
> >
>