RE: Converting to "Pig Power"

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

Original poster: "Randy & Lori" <rburney6-at-comcast-dot-net> 

Adam,

I have a relay rated for 75 amps per leg; is there something special
about a motor starter?  I just figured this relay would cover everything
I'll be doing for a while.

Randy

-----Original Message-----
From: Tesla list [mailto:tesla-at-pupman-dot-com]
Sent: Thursday, March 11, 2004 1:23 PM
To: tesla-at-pupman-dot-com
Subject: Re: Converting to "Pig Power"

Original poster: Yurtle Turtle <yurtle_t-at-yahoo-dot-com>

I have a number of high amperage variacs, including
two at 120 volt 45 amps, three at 540 volt 33 amps,
two at 240/280 volt 28 amps, and a pair of ganged
120/140 volt 20 amp ones, so they can easily be found.
Check for HamFest's in your area, look for scrap yards
and don't forget garage/estate sales, and eBay.

Actually, a pair of ganged 120/140 volt variacs is the
best. When using 240/280 variacs on residential
120/240, one leg is always hot, so you have to be
careful.

Variacs can be driven to twice their current ratings
for short runs if you allow them to stay cool.

You mentioned that you are using a relay. I'd be on
the lookout for a real motor starter, sometimes
referred to as a contactor. You need big contacts to
handle big amps, especially if you want to make or
break during high power.

And finally, if you are limited to a single 120 volt
variac, you can always wire it up vary from 120 volts
to 240 volts, giving you some control.

Adam

--- Tesla list <tesla-at-pupman-dot-com> wrote:
  > Original poster: "Hydrogen18"
  > <hydrogen18-at-hydrogen18-dot-com>
  >
  > Depending on your pole pigs power, you need a variac
  > rated to at least that
  > current. I.E. a 10 KVA pig needs a 10 KVA variac
  > driving it. A 10 kva is
  > both physically and financially illogical(from a
  > producers view). Therefore
  > you might 4x 2.5 KVA variacs with a common shaft and
  > in paralell to make a
  > 10 KVA variac.
  >
  > ---Eric
  > ----- Original Message -----
  > From: "Tesla list" <tesla-at-pupman-dot-com>
  > To: <tesla-at-pupman-dot-com>
  > Sent: Wednesday, March 10, 2004 6:08 PM
  > Subject: RE: Converting to "Pig Power"
  >
  >
  >  > Original poster: "Randy & Lori"
  > <rburney6-at-comcast-dot-net>
  >  >
  >  > I have one large variac (ebay special, No plate)
  > ,but it weighs about 33
  >  > pounds.  I was looking for something on the list
  > that pertains to using
  >  > variacs as inductors, but haven't had a whole lot
  > of luck.  I even read
  >  > where someone has cut the torrid to prevent the
  > current from running
  >  > away.  I'm not crazy about chopping up a
  > perfectly good variac.  I do
  >  > have a question though; why would I need two
  > variacs?  If my primary on
  >  > the pig is run by 240VAC, wouldn't the current
  > through one phase be the
  >  > same as the other phase?
  >  >
  >  > Randy
  >  >
  >  > -----Original Message-----
  >  > From: Tesla list [mailto:tesla-at-pupman-dot-com]
  >  > Sent: Wednesday, March 10, 2004 8:54 AM
  >  > To: tesla-at-pupman-dot-com
  >  > Subject: Re: Converting to "Pig Power"
  >  >
  >  > Original poster: BunnyKiller
  > <bunikllr-at-bellsouth-dot-net>
  >  >
  >  >
  >  > there is one thing missing...    BIG Variacs...
  > at least  2 1256D
  >  > Powerstats  in paralell...
  >  >
  >  > Scot D
  >  >
  >  >
  >
  >