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Re: breaking in caps (fwd)





---------- Forwarded message ----------
Date: Thu, 23 Apr 1998 22:52:53 -0600
From: "D.C. Cox" <DR.RESONANCE-at-next-wave-dot-net>
To: Tesla List <tesla-at-pupman-dot-com>
Subject: Re: breaking in caps (fwd)

to: Bob

Don't run your system without the sec. coil in place.  The increased Q
factor will damage your xmfr or caps or both.  The mechanical analogy would
be racing a car engine to high RPM with the transmission in neutral, ie, no
load.  The system needs to "see" the load offered by the sec coil to
operate properly.  It's best to break in the caps by adding a hv rectifier
and running them on DC for a series of 6-8 cycles and slowly increasing the
variac setting on each cycle.  A 1-2 hour time period per cycle usually
works fine.  DC is a lot easier on homebrew caps for breakin period than
AC.  Do not connect your primary circuit or anything to the caps -- just
run them off the xmfr without a load during this procedure.

Your 4 x 9 toroid will offer a nice match to your system for tuning.  Use
approx 20 turns of scrap house wiring supported on pieces of cardboard on
edge for initial tuning experiments.  Replace later with a nice looking
primary after you have found the tuning range required for your system. 
Usually an additional 4 turns is good as it allows for other loads such as
action-reaction spinners, etc., to be added later and you still have a few
more notches of primary to retune with.

DR.RESONANCE-at-next-wave-dot-net
  

----------
> From: Tesla List <tesla-at-pupman-dot-com>
> To: tesla-at-pupman-dot-com
> Subject: Re: breaking in caps (fwd)
> Date: Wednesday, April 22, 1998 11:09 PM
> 
> 
> 
> ---------- Forwarded message ----------
> Date: Tue, 21 Apr 1998 15:34:09 EDT
> From: Esondrmn <Esondrmn-at-aol-dot-com>
> To: tesla-at-pupman-dot-com
> Subject: Re: breaking in caps
> 
> In a message dated 98-04-21 02:48:41 EDT, you write:
> 
> << Subject:  breaking in caps
>  
>  hi all
>        I am almost ready to start thinking about putting all my bits
together.
>  The primary is finished ,so is the spark gap. The caps should be ready
in a
> few
>  days, havent wound the secondary yet . I was going to do that while
waiting
> for
>  the caps to settle in. My question is about breaking in the caps.  Is it
ok
> to
>  run the system without the secondary? . what I was planning to do was
run the
>  system up slowly to help break in the caps. I know shorted turns are  a
> definate
>  no no but what about  no load conditions? Also what about  RFI from this
set
> up.
>  Do I need to do it away from any electronics/ computers. Also I have
found a
>  cake tin which would make a great toroid. The only problem is it's only
9"
>  diameter by 4" deep. would this do as a first top load to tune my coil? 
coil
>  details secondary  4" x 24" 800 turns 22AWG :  9Kv 50mA neon : 0.0177 uF
cap
>  :10 turns 3/8" primary : RQ spark gap. I havent come across this
question in
> the
>  archives so hope it 's not to obvious. Many thanks
>  
>  bob golding  lightning without rain
>  
>  bob yubba-at-clara-dot-net
>   >>
> Bob,
> 
> Sounds like a nice project.  I would not run the primary without the
secondary
> in place more than a few seconds.  I would complete the whole system then
run
> it at low power for a while for tuning and to break the caps in.  Then,
> gradually increase the voltage until you get the variac wide open.  Many
run
> times at less than full power will help the caps shed the trapped air.
> 
> Ed Sonderman