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Re: Dwell time, etc

Original poster: FutureT@xxxxxxx In a message dated 3/28/06 10:45:35 PM Eastern Standard Time, tesla@xxxxxxxxxx writes: 

Dave,

After the gap fires, the cap is mostly empty of voltage.  It takes
time for the current to charge the cap to reach enough voltage
to fire across the gap again.  This is similar to how a static
gap quenches, then fires again when the voltage reaches
a high enough level to jump the gap.  In the rotary, by the time
the cap has enough voltage to jump the gap, the electrodes should
have passed out of alignment, so no spark will occur until the
next time the electrodes align.  The uncharged cap is holding
down the voltage during the initial cap charge time because the
cap is large enough in value so it takes enough time to fill.  Imagine a
bucket of water with a small hole drilled two inches away from the
bottom (on the side of the bucket).  This hole represents
the still-aligned electrodes of the
rotary.  If you start filling the bucket using a water hose, the
water will not pour out of the hole right away.  First the bucket
will need to fill to the level of the hole.  But during this time
the electrodes move out of alignment thus "closing" the hole.
Then the bucket can fill completely.

John



I'm confused -- if you are wiring the gap across the transformer, as
seems to be the optimum per current thinking, wouldn't the
transformer supply a power arc, limited only by the ballast
inductance, to the gap as long as the transformer output voltage is
high enough to jump the aligned electrodes?

Dave

After the gaps fire, the capacitor will discharge and the energy will
be used up.
When there's no longer enough voltage to jump the gap, the
gap will quench.