Re: Needed 240v to 480v Transformer.

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

Original poster: "J. Aaron Holmes" <jaholmes-at-silicon-arcana-dot-com> 

If that were local to me, it would have been mine, but
when you buy transformers off eBay, the shipping is
often most of the final cost.  I almost bought a pole
pig off eBay some time ago, but the shipping would
have been around $200!  Nuts!  For a 5kVA pig!!
Ultimately I found a local source, saved hundreds, and
got a bigger unit.  If it were me, I'd still do a
little looking at the 480V pig before resigning myself
to having *two* big transformers on my coil.  Then
again, there is something strangely addicting about
collecting large objects that hum at 60Hz when fed
power.   ...and that your spouse frequently questions
your need for :)

Aaron

--- Tesla list <tesla-at-pupman-dot-com> wrote:
 > Original poster: "Hydrogen18"
 > <hydrogen18-at-bellsouth-dot-net>
 >
 > I have seen 15 KVA units of this type go for as
 > little as $3.
 >
 > ---Eric
 > ----- Original Message -----
 > From: "Tesla list" <tesla-at-pupman-dot-com>
 > To: <tesla-at-pupman-dot-com>
 > Sent: Tuesday, July 13, 2004 4:50 PM
 > Subject: Re: Needed 240v to 480v Transformer.
 >
 >
 >  > Original poster: "J. Aaron Holmes"
 > <jaholmes-at-silicon-arcana-dot-com>
 >  >
 >  > 480V dry-type distribution transformers are
 > absolutely
 >  > everywhere on eBay.  Restrict the search to your
 >  > locality and you may even find one you can go
 > pick up
 >  > today!  ...but they're often expensive, often
 >  > three-phase, and often MUCH larger than 10kVA.
 >  >
 >  > However, there is a 10kVA unit on eBay right now:
 >  >
 >
http://cgi.ebay-dot-com/ws/eBayISAPI.dll?ViewItem&category=42881&item=3827440387&rd=1
 >  >
 >  > ...but is your transformer LV side center-tapped?
 >  I
 >  > don't know about 480V pigs (that's what you have,
 >  > yes?), but most 240V pigs actually have two
 > separate
 >  > 120V windings that are placed in series to
 > achieve the
 >  > 240V (so "center-tapped" is not really
 > descriptive of
 >  > reality).  These can easily be reconfigured with
 > the
 >  > 120V windings in *parallel* to allow for a single
 > 120V
 >  > connection without derating the power.  The
 > nameplate
 >  > will generally show the different configurations
 > of
 >  > the LV leads if this is possible.  Even if you
 > just
 >  > have 480V output, you may take a look inside (if
 > you
 >  > haven't already) to see how the windings are
 >  > connected.  Perhaps you would still find two 240V
 >  > windings soldered together in series.  Even in
 > that
 >  > case, I'd prefer breaking the connection and
 > doing a
 >  > little of my own soldering to dealing with *two*
 > big
 >  > transformers at once!
 >  >
 >  > Regards,
 >  > Aaron
 >  >
 >  > --- Tesla list <tesla-at-pupman-dot-com> wrote:
 >  >  > Original poster: "Paul Marshall"
 >  >  > <klugmann-at-hotmail-dot-com>
 >  >  >
 >  >  > I hve a new power transformer for my coil but
 > it has
 >  >  > a 480v Primary. Does
 >  >  > anyone on the list know where I can get a 240v
 > to
 >  >  > 480v power transformer. I
 >  >  > need at least 10kVA.
 >  >  >
 >  >  > Thanks,
 >  >  >
 >  >  >
 >  >  >
 >  >  > Paul S. Marshall
 >  >  >
 >  >  > _
 >
 >
 >