Re: museum capacitors?

to: Jeff

Our firm, Resonance Research, is the world's largest commercial
manufacturer of resonance transformers.  We have been in business since
1971 and have used Maxwell caps extensively.  Our machines are used daily
in musuems throughout the world (over 142 installations) with a usual daily
duty cycle of 4 forty-five minutes shows.  In the past 25 years we have had
only one cap failure --- and that occured in our lab while we were
overstressing a new design for a coil.  I have toured the Maxwell factory
and seen some of their "secrets".  The main one being the number of series
units which requires the film thickness to be around 0.5 mills (.0005 inch)
thick.  This requires special machines in a clean room to handle the
ultra-thin foils and dielectrics.  Human hands never touch the film or it
would tear.  The winders cost around $100,000 per unit and that explains
why the caps are expensive and it is impossible to duplicate these efforts
at home without the special equipment.  Their prices are very fair
considering all the special machines and staff required to make high
quality units that almost never fail under normal conditions.  


> From: Tesla List <tesla-at-pupman-dot-com>
> To: tesla-at-pupman-dot-com
> Subject: museum capacitors?
> Date: Wednesday, December 16, 1998 7:33 PM
> Original Poster: corr-at-enid-dot-com 
> With all this talk about capacitors I began to wonder :
> What do Tesla Coils used in museums use as capacitors.
> I have heard something about some of them have been there
> for thirty or fourty years.  Do the caps in them ever fail at all?
> Or are they just replaced every once in awhile, and if so, how
> long is that interval.  
> Do they know something about the construction of caps that
> we don't?
> Jeff Corr
> Oklahoma Tesla Coil Builders Assoc.
> corr-at-enid-dot-com