ECN Forum Forums Photo Discussion Forums Photos for General Discussion Primaries of pole mounted transformers

That could just be open delta wired wye primary. Actually pretty normal here using 2 transformers. One of the transformers is center tapped on the secondary and off you go.
I can get a picture of that at the "shop and rob" at the end of my street.

Yah, I've seen that 2 transformer connection very often. But those transformers are usually connected to a 4 wire wye system with a grounded neutral.

I found a picture of a transformer like I was asking about:


http://www.electricalphotos.com/showphoto.php/photo/425/ppuser/28

This picture is very similar to the one I seen in that other book. Could it be a three phase unit or not?

Okay, I happened to catch one in the background of a pic I took today (yes of traffic lights).



Closeup of single transformer:


Ian A.

Re: 3 phase rectangular pole mounted transformers..
Ya usually the PoCo will use 3 separate cans for a 3 phase service drop to a large building but it is NOT uncommon to see a single 3phase transformer of 150 KVA or less on a pole. Usually I have seen them where a building is an older one and had a separate 3 phase service strictly for an elevator or other motor driven equipment.

Don't worry fellas, I am working on those pix still. I know where there is a nice brand-new installation of one of these transformers, right outside my friends 7'th floor balcony.. I will have them in the next few days!

A.D

I have never seen 2 transformers wired wye secondary. It is usually red leg delta around here.

Sorry I should have been more clear. I meant to say the Primary is wye connected.(each transformer is connected phase to neutral). Yes the secondary is open delta with a high leg.

10-4 That sounds regular here. I will try to remember my camera tomorrow.

This is the label on a 50KVA like the one at the top of this thread.

The 50 KVA up close

Here is an American open delta setup with a 3-wire (no MGN) primary. Grounding is done by local rod at the pole. This particular setup is in the high desert area in Sothern California Edison territory where I noticed that most, if not all of the local distribution, was done with no MGN and the transformers connected L-L. This would be considered unusual by US standards which is mostly MGN distribution.