Re: Peak Primary currents (was Re: MMC bleed resistors)

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

Original poster: "Robert Jones" <alwynj48-at-earthlink-dot-net> 

Hi Mark,

----- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Saturday, March 13, 2004 9:48 PM
Subject: Peak Primary currents (was Re: MMC bleed resistors)


 > Original poster: Mark Broker <mbroker-at-thegeekgroup-dot-org>
 >
 > Actually, if there are more strings of MMCs and the same overall
 > capacitance is maintained then the current is shared more or less equally
 > amongst the strings.  So two strings will have half the current of a
single
 > string.

Assuming the charging voltage remains fixed (and frequency) as you increase
the number of strings you increase the number of caps per string to maintain
a given total capacitance..
Which is just a round about way of saying the charge voltage across each cap
is reduced.

If  for some reason small TCs are generally designed with a low charge
voltage across each cap then your statement is true.

I think a better statement for you to have made would have been the caps are
usable if used in a low frequency system (big secondary and or  more turns
than general) and or only charge them to a low voltage compared to their max
rating. This would avoid perpetuating the myth that small coils or adding
extra strings ( fixed caps per string) decrease the peak cap current. ie its
a voltage and frequency.

When I tried to design an geek cap MMC for a small coils( 8in x 1.25in) I
had have only 200v across the geek cap to keep the peak current within spec
else it would have been 5000A.

Bob