Original poster: Don Murray <don@xxxxxxxxxxxxxxx>
Justin,
What the Y means is that if you are going to connect that
transformer to a 12470 volt system you must connect it Y. Each end of
that Y is one phase of a 12470 volt system and each leg of the Y
would be one 7200 volt coil. On a delta system each corner of the
triangle is one phase of a 7200 volt system and each side would be a
7200 volt coil. Draw it out and you will see. What determines if we Y
or delta the high side is coil rating and primary voltage, if they
are the same it will be delta, if primary is higher it will be Y or
star as they are the same. And what determines if you get a delta or
Y low side is the service voltage you want. If you want 120/240 it
will be delta, if you want 120/208 it will be Y.
On the high side of a Y connected bank of transformers you don't
always ground it. Some times you let it float. And you don't always
have to have 3 transformers, you can have open delta and open Y with
2 transformers.
I have some transformer connections on my web page that I put up for
a discussion on a usenet group, thought they might help some. The
Scott connection at the bottom of the page is for 3 phase to 2 phase.
They take special transformers and are pretty rare.
http://murrayranch.com/Electricity.htm
Don
Tesla list wrote:
>Original poster: Justin <rocketfuel@xxxxxxxxxxxxx>
>
>Hi All,
>Just an update, here are the specs on the pig:
>15KVA
>Rated Volts: 7200/12470Y 120/240
>2.2% impedence
>Orto Filled
>http://jay.g-cipher.net/pig2.jpg
>http://jay.g-cipher.net/pig1.jpg
>
>I'm curious what the Y means in the "12470Y"...any ideas?
>
>Thanks as always!
>Justin
Snip>