Re: HV power supply

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

Original poster: "Jim Lux by way of Terry Fritz <twftesla-at-qwest-dot-net>" <jimlux-at-earthlink-dot-net>

If you look at the energy actuall required to deform the metal, you'll see
that 4-5 kJ is more than enough (this is like the amount of energy stored in
lifting a 100 kg mass 5 meters in the air!).. The key is in efficiently
putting that energy to work shrinking the quarter rather than heating the
system, deforming or destroying the work coil, etc...

As a practical matter, I've shrunk quarters with less than 3 kJ..
----- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Monday, May 13, 2002 6:57 AM
Subject: Re: HV power supply


> Original poster: "Paul Marshall by way of Terry Fritz
<twftesla-at-qwest-dot-net>" <klugmann-at-hotmail-dot-com>
>
> Sorry, I see two problems here one with 10 ma youll never charge your cap.
> The energy will bleed off faster than you can apply it. The second problem
5
> Kj isn't enough to shrink quarters. You have to be above 6 and preferable
7
> Kj to get started.
>
>
>
>
> >From: "Tesla list" <tesla-at-pupman-dot-com>
> >To: tesla-at-pupman-dot-com
> >Subject: HV power supply
> >Date: Sat, 11 May 2002 20:41:47 -0600
> >
> >Original poster: "by way of Terry Fritz <twftesla-at-qwest-dot-net>"
> ><Tesla729-at-cs-dot-com>
> >
> >Hey all,
> >
> >I'm sort of looking for a decent metered, filtered HV power supply
> >without spending a  fortune. I am looking for something that
> >can put out at least say 20 kVDC at at least 10 mA. I've been
> >looking on ebay some for this but it seems hard to find exactly
> >what i'm looking for for under $300, especially when you start
> >figuring shipping. I'm needing something like this to charge my
> >(2) 100 uFD, 10 kV energy discharge caps for my quarter shrinker
> >safely within a reasonable time frame ( < 2 minutes for a 10 kJ
> >charge is what I'm aiming for). I'm no engineer, but I know that you
> >can charge a cap a lot faster if the supply voltage is considerably
> >higher than the voltage that you are trying to charge the cap to,
> >so long as you quit charging when the cap reaches its rated voltage.
> >My current charger uses (2) 15/30 NSTs full wave rectified thru (2)
> >diode sticks from an x-ray tranny to the center tap ground of the
> >NSTs. Even when fed by a variac with 140 volts, these output DC
> >voltage with the load of charging these caps dosen't get much above
> >10 kV, so I can charge the caps to say 80% of their rated voltage
> >within a couple of minutes but it takes almost forever to fully charge
> >them to 10 kV :-(
> >
> >Anyway, a nice little HV power supply like Terry has would be nice :-)
> >Anybody got an extra HV supply that they would like to sell to a good
> >home for a reasonable cost? Or can someone point me in the right
> >direction for obtaining one?
> >
> >Spark Safely,
> >David Rieben
> >
> >
> >
>
>