Re: Theory - primary cap duty -transformer output current

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

Original poster: "Malcolm Watts by way of Terry Fritz <twftesla-at-qwest-dot-net>" <m.j.watts-at-massey.ac.nz>

Hi Scot and all,
                 I can do no better than refer you and anyone else 
who is trying to grasp the essence of capacitor charging to Ritchie 
Burnett's two excellent posts on the subject, posted during the 
preceding couple of weeks. They should be easy to find in the list 
archives (soon if not now). Also, when discussing LC circuits of any 
sort in relation to zero-crossings, let us all know whether you are 
referring to voltage or current zero crossings. As I'm sure every 
Teslarite appreciates, the two do not coincide in LC circuits. To 
give an example - when the voltage across a capacitor hooked to a 
neon sign (or ballasted) transformer coincides with the voltage 
across the terminals connected to the capacitor, the capacitor 
current must be zero. Seems obvious does it not?

Malcolm

http://www.richieburnett.co.uk/
Oops, Richie's site is down. - Terry

On 3 Jul 01, at 17:33, Tesla list wrote:

> Original poster: "BunnyKiller by way of Terry Fritz <twftesla-at-qwest-dot-net>"
<bigfoo39-at-telocity-dot-com>
> 
> Tesla list wrote:
> 
> > Original poster: "PotLuck by way of Terry Fritz <twftesla-at-qwest-dot-net>"
> <potluckutk-at-earthlink-dot-net>
> >
> > My inquiry focuses on transformer current and the primary cap.
> > My understanding is that once the primary cap is charged and the firing
spark
> > occurs that the transformer's current during the HV pulse and "ringing"
> are no
> > longer a factor, that the energy stored in the primary cap becomes the sole
> > provider of current in the tank circuit.
> 
> Snipperzz...
> 
> HiPot     ( snickerz) its a joke HiPot test ....
> 
> anyway ...   there are 2 schools of thought on cap charging and
> discharging...   some say 4 times
> per full cycle some like 2 times per cycle...
> 
> the 4 times per cycle is when you take the starting voltage at 0 degrees (
> 0 V ) and allow the first
> 90 degrees to charge the cap to a " positive " full volt rating, fire the
> gap there ( SRSG works
> great here) the full potential of the charged cap gets dumped into the
> primary at this time. From 90
> degrees to 1880 degrees the "Positive" voltage is on the down fall ( this
> is where i get lost) ((
> only thing I can think of is that the voltage from "full" to dropping does
> allow a bit of charge to
> fill the cap as it is falling, but the time it has to do it in is minimal))
> at 180 degrees the gap
> fires again, thus discharging that bit of charge in the cap. Then we swing
> into the " negative" side
> of the voltage swing ( V going negative on the sine wave) and this charges
> the cap in the reverse
> polarity ( this is why DC caps dont work with coiling ) at 270 degrees the
> gap fires again at full
> "negative" voltage. and the cycle continues .......
> 
> the other idea is that the cap gets charged to full positive voltage at 90
> degrees and cap is
> discharged at that point...  and time is allowed to let the voltage after
> the initial firing go back
> to 0 volts ( ??? ) at 180 degrees. This then reverses and the negative
> voltage begins to increase to
> the opposite potential.. and at 270 degrees the gap fires again....
> 
> Heres the clincher tho....  just after the gap fires, the primary coil and
> cap do the oscilation
> thing ( this is what allows the secondary to be matched in frequency (
> tuning the primary) This
> oscillation action removes alot of the power and voltage from the cap ((
> this must happen fast cuz
> how else does the cap get recharged ???  my turn for a question ... how
> about it you electro gurus
> got the answer for me ??  ;)  ))
> 
> another question...   when the gap misfires how does this overcharge the
> cap and blow it? where does
> this extra voltage come from??
> 
> sheeshhh  now im thinking again ;)
> 
> 
> Scot D
> 
> 
> 
> 
>