Re: static "sucker" gap / cap stress

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

Original poster: "Christoph Bohr by way of Terry Fritz <teslalist-at-qwest-dot-net>" <cb-at-luebke-lands.de>

Hi Terry.

That's good to know, I already feared that this behaviour is normal under
such stress for the cap.
Ich checked the spec sheet for my cap and it says the cap is rated for 500
beats continous, I probably go much higher.
Unfortunately there is no information on what the dielectric layers are made
of, only that the oil is PCB-free
Like in CPU cooling the bad thing is that the outside tempareature is not
really a good indicator for what is giong on deep inside....;-)
Maybe I will be able to buy another of these caps and by adding capacitance
reducing the number of shots per second or in series to reduce voltage
stress.
I already limit the output current of the supply with the 4 MOT-caps i got
from the MO's but it still seems far too much for the cap.
I think I will try to lower the current, although I might drop the output
voltage to a point where effective operation is impossible...will see.

Thaks for the information!

Christoph



----- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Wednesday, April 23, 2003 9:03 PM
Subject: Re: static "sucker" gap / cap stress


 > Original poster: "Terry Fritz" <teslalist-at-qwest-dot-net>
 >
 > Hi Christoph,
 >
 > At 07:50 PM 4/23/2003 +0200, you wrote:
 > >
 > >Questions to be solved: Cap heating.....is it bad or not......dont want
to
 > >destroy it as its my only professional pulse cap.
 > >
 >
 > Significant cap heating is always a worry.  If it is polypropylene, it
will
 > melt when any part of it (deep inside the winding) gets to 85 to 105C.  If
 > it is paper, the losses will be high which makes it get hot fast and can
 > possibly blow the oil out of it.  So let it cool between runs and watch
 > that it's temperature never gets too high.
 >
 > Cheers,
 >
 >          Terry
 >
 >
 >
 >