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CAPS IN SERIES

 > pierson-at-cimcad.enet.dec-dot-com
 > Subject: Caps in Series


 dwp> In addition to previous points re resistors to force 
 dwp> voltaeg division:

 dwp> 1) AC voltage should divide equally IF the caps are equal.  
 dwp> Usually caps are +/- 10% so even equal caps aren't.

I guess I must be the exception to this rule. I measure my capacitors,
each and every time I hook them up to fire. This goes twice for home-
made capacitors which have a tendency to drift in value. This drift is
especially notable during break in (where a 10% drift is normal in the 
first three days), and after both; hard runs, or prolonged dormancy.

 > 2) Especially in cases like this, a safety gap across _each_ is 
 > a good idea. Nothing elaborate, just some bits of wire far enough 
 > apart to not normally arc over. (IMO, safety gaps across everything 
 > with voltage across it are not a bad idea, saving "rapid disassembly" 
 > if the power gets to the wrong place....) 

Now we are talking. This is a first rate idea, and I agree 100%. I will
add my own little complexity... Put a grounded center tap between the
two hot electrodes of the safety gaps across the capacitors, and if things
go "high order" (pure entropy), the available energy for destruction of 
valuable components will be partly dumped, not just returned to the other
side of an already stressed capacitor dielectric. This is both safe,
effective, and high Q; as opposed to using megaohm resistors across 
pulsing caps.

 dwp> (and it can be properly said that this is just one more
 dwp> complexification that can be avoided by using, if need be 
 dwp> building, the right thing in the first place.) > regards dwp

I have heard much wisdom today, and wisdom such as this never tires me.

Richard Quick

... If all else fails... Throw another megavolt across it!
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