Re: TC Secondary Electrostatic Charge
Subject: Re: TC Secondary Electrostatic Charge
From: "Malcolm Watts" <MALCOLM-at-directorate.wnp.ac.nz>
Date: Fri, 15 Mar 1996 10:31:05 +1200
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The ongoing observations of residual charge on the secondary
insulation seems to warrant an investigation into the mechanisms
involved. Something I'll commit myself to later this year.
> I found that when I move a fluorescent lamp up and down about an
> inch from th e secondary winding of my Tesla coil after it has been
> disconnected from the mains, the lamp flashes. This phenomenon
> will occur for several hours after the TC has been operated. The
> secondary coil is wound with magnet wire on a PVC tube and heavily
> insulated with styrene paint (Q dope). I suspect that this effect
> is due to residual charge stored in the secondary capacitance.
> If I let it sit for a while after having generated many flashes
> and seemingly discharged the capacitance, it recovers. Any
> theories about what is going on ?
I think you are experiencing dielectric memory. The general rule I
apply to capacitors is : _never_ assume the cap is fully discharged
just because you have discharged it. A safe capacitor is one with
a short applied to its terminals. I have been bitten more than once
like this. What seems to happen is that the stressed dielectric slowly
unstresses over a period of time.