[Prev][Next][Index][Thread]
Re: 2 questions on resonance
In a message dated 99-04-09 04:59:33 EDT, you write:
><< >resonant charging. The formula is:
> >
>> > C = I/(2Pi*VF)
> >
> > where: I = total sum of faceplate rating of NST bank in ma
> > V = faceplate RMS in kilovolts for NST bank
> > F = incoming line freq in hertz
>> C = microfarads
> > Pi = 3.1416
> >
> All in all, I agree. However, my question is the definition
> of "I". While Jon R.īs NST(s) didnīt seem to care about
> the shunt removal (meaning the resocap size), I found
> that I actually can tune the NST to the cap, by adjusting
> the shunt. I think it is probably better to actually
> measure the NST current (esp. if you are paralleling a
> few), then just trust the faceplate values.
I agree, but usually the acceptable range of cap sizes is quite
broad, for instance I saw absolutely no difference in output using
.006uF, and .0077uF in my coil. I see the matching as a ballpark
thing, and I often make the cap a little larger than the formula calls
for. For instance I use .0147uF where the formula calls for .011 or
so.
Concerning using resonant charging with sync gaps with unshunted
transformers, I recommend it for obtaining max efficiency from a coil.
The technique seems also seems to provide max spark output from
an NST powered TC, but I'll be doing more tests. With high break
rates, the transformer is being shorted often in weird ways,
depending on where on the sine wave, the gap fires, etc.
John Freau
> Coiler greets,
> Reinhard
>>