Re: do i want a wye wye or delta pole pig?

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

Original poster: Harvey Norris <harvich-at-yahoo-dot-com> 


--- Tesla list <tesla-at-pupman-dot-com> wrote:
 > Original poster: "Crow Leader"
 > <tesla-at-lists.symmetric-dot-net>
 >
 > Unless you have three phase service, that
 > transformer is just a 5kVA unit to
 > you. Do they have something in 10kVA single phase as
 > well? That would be
 > more useful, assuming you don't have three phase
 > power.
 >
 > KEN
Check out
http://www.elec-toolbox-dot-com/usefulinfo/xfmr-3ph.htm

Three-Phase Transformer Connections:

There are only 4 possible transformer combinations:

Delta to Delta - use: industrial applications
Delta to Wye - use : most common; commercial and
industrial
Wye to Delta - use : high voltage transmissions
Wye to Wye - use : rare, don't use causes harmonics
and balancing problems.

I had a 25 dollar deal on a Step down Delta to Wye
transformer. Of course to use it as a step -up of
voltage, I had to wire it backwards. This is something
to consider if we are using our own alternator
generated 3 phase emf.  This is because every design
to my knowledge uses a internal stator wiring in wye,
simply because that combination yeilds the result of
outputing a higher stator voltage, where we are then
using two (internal)stator coils in series to obtain
that WYE output. When we hook that WYE output to the
WYE input of the transformer, to procure the Delta
step up of voltage, we are then using the 4th
combination that causes balance problems. These
aspects showed itself as different voltages coming out
on the delta outputs, as I recall this may have been
on a 1;2;3 ratio, for 100,200 and 300 volt outputs on
each of the different phases.
HDN