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30 BPS, 60 BPS tests



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From:  John H. Couture [SMTP:couturejh-at-worldnet.att-dot-net]
Sent:  Monday, March 09, 1998 11:22 PM
To:  Tesla List
Subject:  Re: 30 BPS, 60 BPS tests


  John F. -

  Your tests again brings up the question of how should a Tesla coil be
properly metered when using only random sparks as the output. When
continuous sparks are used metering the continuous input watts is the
correct method to use. However, this is not an accurate way to measure the
input for a TC with random spark length output.

  Because the TC system contains capacitors it has the ability to store
electrical energy over more than one spark gap operation. This means the
electrical energy can build up in the secondary circuit and provide one
extra long random spark. This type of operation is obvious because the
random sparks emitted from the secondary terminal are not of the same length
indicating different amounts of voltage and energy on the secondary terminal.

  Note that the charge on the secondary would not be returned to the primary
with a properly designed TC. This is because the gap quenches after the
energy leaves the primary and the energy is in the secondary. If the energy
returns to the primary the gap is not quenching properly.

  Because of the random spark output the input metering must be different
than with continuous sparks. The main problem is that the input wattage for
random sparks is not an RMS condition (sorry Antonio). This means that
several parameters must be metered at the same time to obtain correct
results. The parameters include volts, amps, wattage, power factor, and
intervals of time. This  combination of parameters is required to determine
exactly the amount of energy associated with a particular random spark length.

  To my knowledge no one has ever shown the details of how this metering for
random sparks should be done.

  Coments welcomed.

  John Couture

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

At 11:02 PM 3/6/98 -0600, you wrote:
>
>----------
>From:  FutureT [SMTP:FutureT-at-aol-dot-com]
>Sent:  Friday, March 06, 1998 8:04 AM
>To:  tesla-at-pupman-dot-com
>Subject:  30 BPS, 60 BPS tests
>
>All,
>
>I did some more tests with the sync gap TC at 60 BPS.  At 400 watts
>it gave 31" sparks, at 480 watts it gave 36" sparks, and at 640 watts
>it produces 46" sparks.  At 600 watts it gives 45" sparks.  Below 400 
>watts it runs very weakly.  For the 400 watt test, I had to replace the
>5" x 20" toroid with a 4" x 17" toroid to obtain adequate break out.
>These are some of my best results so far.  I don't know how accurate
>the wattmeter is when only one polarity of the AC is loaded in this way.
>Perhaps I'll set up the thermocouple ammeter to see what gives.  The
>sparks have a nice way of surging out to long lengths in this coil, I'll
>discuss this surging in another post.
>
>I also tried 30 BPS, but results were poor.  The sparks emitted from all
>around the toroid and were very short. This low break-rate seemed
>unable to maintain a properly ionized streamer with this coil 
>configuration, both with the original sized capacitor, and when the
>cap size was doubled.  It produced an interesting sound however.
>
>The coil was powered in all tests by a 14.4kV, 1.5kVA potential
>transformer with an adjustable inductive ballast.
>
>John Freau
>
>
>