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Re: Odd numbers

Hi Marc, 

Tesla list wrote: 
>
> Original poster: "Metlicka Marc" <mystuffs-at-orwell-dot-net> 
>
> bart, 
> this may all come down to the analogy that voltage is the size of a 
> river and current is the speed of the river. since speed\distance and 
> time are all interrelated, the 28\120 pt has more winding length for the 
> induced v too travel, the three nst's have 6 windings all working as 
> one, but the unit winding length is short. even if the electron travels 
> at the speed of light (actually a little less due to resistance, causing 
> heat) it still takes time? 
> marc

Time is directly related. It's the transformer impedance defining the charge
time when the cap size is unchanged and the Vrms/Irms is identifying the
impedance. It's just ohms law really. Increase voltage and you increase
impedance which directly effects charge time. To increase charge time, the
current needs to be increased OR the capacitance decreased. BTW, cap charge
times are not linear. A cap will charge to 63% in 1 time constant (RC) but the
cap will not charge to full charge (99.9%) until 5 time constants have gone by
(5RC). 

In "my" Ed Sonderman Excel rendition (the spreadsheet), I always look at Vp
(for RSG's only) at the cap by what the "standard" charge time is for the
system and then look at the BPS time to find just what the actual Vp is at the
cap at the time of conduction, which works ok for a 120BPS, but what is really
needed is to know at what point along the AC 1/2 cycle the break is occuring.
This identifies Vp and Ip and therefore cap watts. As you can imagine, at
faster break rates this task gets ugly (in Excel) - now PSpice modeling has no
problem identifying this information. But again, PSpice has the unique ability
to show just how complicated TC's are where ALL math calcs can do the basics,
but there's no way a math calc can identify points in time without software
such as ORCAD, where electrical occurances are sampled at extremely small
points of time. 

Take care, 
Bart