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Re: 50 KVA Power Supply

I wrote:

 > I was going to set up the Jacob's Ladder and get some good     
 > photos of the new power supply while running the rails. Since  
 > I could not I had my brother shoot the rest of the roll up on  
 > the 22890 volt pig while harnessed to the ladder. The film     
 > went up to the drugstore today, I should have scans soon.

Quoting Bert:

> The Jacobs Ladder off this beast sure looks awesome in your 
> video!

Thanks!

> Are you planning to run your new pig-pair higher than the 16 
> KVA rating of your present control box? After all, you have 200
> A service and a 100 A drop to your coil. More power, More 
> power... 

I will let you in on a little secret. I have yet a third matched
variac which will shaft mount with the pair I have already ganged
up... Yet if the load on the variacs is constant (not surging or
spiking), they will easily handle intermittent service of twice
the plate rating without complaint. Figure the cabinet will
handle ~100 - ~130 amps at 280 volts without much trouble for
runs under a minute. The fuses on the variacs need to be upgraded
for this purpose, but the existing fuses are "slo-blow" type and
I have already pegged the ammeter at 100+ amps a few times
without any indication of difficulty. Figure everything I am
building and rating meets commercial/industrial specs for
continuous duty.

Even the industrial continuous ratings are under rated: I had the
electric company out here a few months ago when an underground
cable linking my house to the pad transformer supply failed. The
failed cable had all aluminum conductors and a small cut through
the insulation allowed moisture to enter whereupon one conductor
corroded through.  We spliced in a shunting cable across the
drive and over the lawn next door as a temporary fix. The shunt
cable consisted of three conductors of #2 AWG aluminum. Off the
cuff I asked the utility electrican how much current it could
safely carry, he told me that in practice he has put up to 600
amps through the same cable without excessive heating. The same
cable caries a load rating in the book which is much smaller than
600 amps.

Richard Quick


... If all else fails... Throw another megavolt across it!
___ Blue Wave/QWK v2.12