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Re: It Just Stopped



Original poster: "Hydrogen18" <hydrogen18-at-bellsouth-dot-net> 

I'd contact the seller and tell him you were cheated out of the oil and want
to be reimbursed in full.

---Eric
----- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Tuesday, August 03, 2004 8:07 AM
Subject: Re: It Just Stopped


 > Original poster: Mddeming-at-aol-dot-com
 >
 > Hi Sean, All,
 >
 >      I think the cause has been found. While preparing to send it for
 > post-mortem analysis, I discovered that it contained less than a
 > teaspoonful of oil. Evidently, the eBay vendor I bought it from 2 years
ago
 > drained it before shipping, but failed to mention this fact. If it can run
 > as well as it did empty, think of what it will do when full ;-))) I
realize
 > it may be toast already, but at $55 per, it's worth a try before burying
 > it. I guess the lesson here for all is "Never assume anything on eBay is
in
 > plug-and-play condition."
 >
 > Thanks for the suggestions,
 > Matt D.
 > Old dog learning new trickery
 >
 > In a message dated 8/2/04 10:39:32 PM Eastern Daylight Time,
 > tesla-at-pupman-dot-com writes:
 > Original poster: "Sean Taylor" <sstaylor-at-uiuc.edu>
 >
 > Hi Matt,
 >
 > Assuming both the NSTs are fine past 6000 Volts (IE no internal arcing
that
 > starts at around 6,500 V :-) ), then I would guess your cap failed to a
 > short.  Even though you're measuring something at low voltage, there may
be
 > carbon tracking that is shorting the cap out.  LCR meters are typically
 > designed to measure capacitances with a series or parallel resistance so
 > it's possible a ~10 kOhm resistance is effectively shorting your cap
 > causing the meter to read approximately correctly, but the cap to
 > effectively short your transformers.  Check the DC resistance of your cap
 > (after shorting it to make sure there is no charge), and the meter should
 > go to showing and open circuit.  However, the 0.5% change you show in the
 > capacitance isn't very much and could easily be the temperature affecting
 > the meter and/or capacitor.
 >
 > I think most people would say that using that cap with a 15 kV transformer
 > (and at that current) is pushing it a bit (if that's one of the 37667 caps
 > - 35 kV, 30 nF).  I would build an MMC for that set up with 2 strings of
10
 > caps each of the 0.15uF, 2 kV CDE 942C series caps.  Unfortunately, since
 > The Geek Group is out of them right now, you'll have to find another
source
 > such as Richardson Electronics - http://www.rell-dot-com.  I haven't ordered
 > from them in quite a while, but when I did, it took about 2 months to get
 > the caps, and there was a minimum order of 27 or so caps.
 >
 > Before you order new caps though, you may want to use a string of diodes
 > and charge your cap up to 20 kV or so and see if it holds a charge, or
 > requires excessive current in to maintain that charge.
 >
 > Good luck figuring it out!
 >
 > Sean Taylor
 >
 >