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Re: Coil problem



Tesla List wrote:
> 
> Subscriber: FutureT-at-aol-dot-com Sat Jan  4 21:22:55 1997
> Date: Sat, 4 Jan 1997 01:48:41 -0500
> From: FutureT-at-aol-dot-com
> To: tesla-at-pupman-dot-com
> Subject: Re: Coil problem
> 
> In a message dated 97-01-04 00:51:39 EST, you write:
> 
> <<
>  >  -- Bert --
>  >   >>
>  > I've been using motor starter capacitors for PFC on my neons,  why are
> these
>  > caps undesirable; danger of shorting out and/or blowing up?
>  >
>  > Happy coiling,
>  >
>  >    John Freau
> 
>  "John,
> 
> "> Motor starting caps tend to be rather inexpensively made, planned for
>  only intermittent usage, have higher Equivalent Series Resistance, and
>  generally tend not to be nearly as "robust" as film caps made for
>  continuous duty (and generally higher voltage). If you run motor
>  starting caps for relatively brief times during coiling, they may work
>  OK. But if you can get better ones cheaply, its probably wise to do so.
> 
>  BTW, have you noticed any heating or cap failures when using these as
>  PFC's? Since I've not to used them (for the above reasons), I don't have
> > any run-time experience with them.
> 
>  >-- Bert -- "
>   Bert,
> 
> No failures yet,  I use the ones with the black bakelite plastic tubular
> cases that have a metal toothed ring pressed into the end to hold in the evil
> guts of it.    I can't remember for sure if they got warm or not--it's
> possible they got a little warm.  I know if they got quite warm, I would have
> remembered it.  BTW, I used them on a 12 kV, 30 ma unit.  I tried both 26 uF
> and 56 uF values (not at the same time), didn't make much difference in
> current input or spark output.  But either value of course reduced the
> current compared with no PFC at all.

John,

Well, I can't argue with success! I'd always been told that these
puppies were for intermittent duty only... but heck, that's what coiling
is! I've never seen ANY change in coil performance either - just a
change on how long I can run before popping the breaker! :^)

Safe coiling to you!

-- Bert --