Re: Sync Gap Timing (phase angle considerations)

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

Original poster: "Peter Komen by way of Terry Fritz <twftesla-at-qwest-dot-net>" <pkomen-at-zianet-dot-com>

----- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Sunday, November 17, 2002 5:30 PM
Subject: Re: Sync Gap Timing (phase angle considerations)


 > Original poster: "harvey norris by way of Terry Fritz
<twftesla-at-qwest-dot-net>" <harvich-at-yahoo-dot-com>
 >
 >
 > With an inductive reactance it is commonly stated that
 > the resultant amperage lags the impressed voltage by
 > 90 degrees on the AC cycle. This may not be entirely
 > true as it should lag the impressed voltage by the
 > phase angle that inductor makes by plotting out its
 > resistance and its inductive reactance with y and x
 > axis', but here we are only concerned with how the
 > amperage in time from the displacement current on the
 > capacity will act with respect to its voltage input.
 > It does the opposite effect as the inductor, so it is
 > said that the voltage across the cap will LEAD the
 > impressed voltage by ninety degrees. We can ask the
 > question, when in  the time of the AC current through
 > a capacity  does the capacity contain the greatest
 > voltage? Obviously in this case the greatest voltage
 > across the cap concurrently occurs with the point when
 > greatest amperage is occuring across the cap. But IT
 > IS THAT AMPERAGE WITH RESPECT TO THE INPUT VOLTAGE
 > THAT IS ITSELF 90 degrees out of phase with the input.
 >
Harvey,

For a capacitor across an AC voltage source, the voltage on the cap must
match the voltage source.  There cannot be different voltages at the same
point in the circuit.  The current in the cap is proportional to the rate of
change of the voltage.  The slope of the voltage curve gives the current.
The greatest slope is at the zero crossing of the voltage.  For a TC primary
circuit, the primary coil is such a low inductance that it can be ignored at
60 Hz

  For a TC (especially one using a NST), caps are chosen to use the maximum
energy that can be extracted from the transformer.  Resonant sized caps or
LTR caps give the maximum capacitance and maximum voltage and therefore the
most energy storage.  Smaller caps don't use all the current capability;
larger caps don't use all the voltage capability of the current limited
transformer.  Given the secondary current and voltage and the supply
frequency, the resonant cap size can be calculated.  The gap should be
fired when the capacitor contains the most energy which is at the voltage
peak (the trough is just a negative voltage peak.) or a little after the
peak  When the current stops in the cap, that is the maximum voltage (unless
it's discharged to zero).

I don't have time for more detail right now.

Regards,

Pete Komen