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RE: Unpowered NST shocks



Comment interspersed.

>Original Poster: "Reinhard Walter Buchner" <rw.buchner-at-verbund-dot-net> 

> the guy who started
>this thread shorted the NST AFTER removing power, so this
>canīt be the reason ;o)

I guess I missed that, so this may all be achedemic, though interesting...

>> However, I also tried a simple experiment on my bench.  I took a 15/30
>>NST and hooked a NE-2 bulb across the 2 HV bushings as a HV spike
>>indicator.  I also shorted the two bushings with a separate clip lead.
>>I briefly applied, then removed AC power from the primary, and within
>>1-2 seconds, removed the short from the secondary.  I repeated this
>> several dozen times, but never once saw the bulb flicker.

>In the same mail, I pointed out this is EXACTLY my comprehension
>problem. No inductor is lossless. By the time you pull the plug and
>open the short (takes several seconds at best), the stored energy
>will be lost to internal losses (and turned into heat). I DO believe
>this will work in a LTR designed coil as the inductor is shorted and
>opened many many times per second (depending on the BPS rate)
>through the spark gap.

Agreed that no real inductor is lossless, but with a value in the thousands
of Henries, it will in fact take several seconds, even with resistive losses
in the multi-kilohm range, for the current in the loop to decay. Don't
forget, the time constant for 1000 Henries and 1KOhm is one second.
MicroSim is great for showing this!  I have no explanation for why I was
unable to demonstrate this on the bench.  Perhaps the secondary inductance
is non-linear...?

<snip>

>Coiler greets from Germany,
>Reinhard

Regards, Gary Lau
Waltham, MA USA