Re: Now, How does a coil really work??
In a message dated 1/26/99 5:22:19 PM Pacific Standard Time, tesla-at-pupman-dot-com
> I agree, it was a good question and a good answer. So many times I've
> coilers using static gaps but they always assume 120bps (60hz) or
> 100(50Hz). Most
> really don't know and assume this. I'm curious how often we can fire the
> during a cycle? Is there a major limitation beyond electrical or
> stresses? My first thought at this I came up with 4 x main freq., but
> more I
> think about this, I bet the gap could be fired quite a few times during
> Not sure what you mean by "how often can we fire the gap....", but the
> answer is many times per half-cycle of the line frequency if you set the
> gap small enough. On the other hand, if you set the gap wide enough (and
> your transformer doesn't short), or if you reduce the primary voltage to
> your transformer, you can get the gap to fire once every few cycles if
> the capacitor is series resonant with the transformer leakage
> inductance. (This is sometimes called "the matched capacitor". You can
> get all sorts of chaoatic behavior too.
> I've run a number of simulations which produce results which agree very
> well with my observations, considering the simplifications involved.
> Should collect some of the predicted waveforms and have them ready to
> send to anyone who is interested.
Another consideration is quenching. If you start out with say 12 kv at 60 ma
for a power supply, then steadily add increased current capacity, you will get
to a point where a static gap will fire at a higher and higher rate (bps) and
then will not quench - it will stay fired. Then you can add vacuum or air
blast and go up to a new higher current limit and finally that gap will not
quench either. Then you finally will need to go to a rotary gap. And, if you
continue this saga, I suppose the rotary will need to get larger (contact size
and wheel size) as more current yet is added.