at my house....

there is one transformer that one high voltage (9kv around here) input and 3 120v outputs - the outputs are wound/wired so that they are out of phase with
each other (how far - not sure, the 180* number seems most correct but flies in the face of what I see behind my house)

Each house only get 2 of these 3 phases. (incl mine)
Now sure how this makes my dryer and A/C work, but they do.

let me look outside and be sure...

Yep, 1 xfmr, 1 lead in, 3 leads out. the 3 leads run the length of the road and each house gets 2 of the 3 leads.

I can see that making 3-phase lets them power a 3 phase business with it somewhere.

This also lets your transformer "lose a phase" which causes some houses to lose power and some not.

The only memory of failure I have is when a tree fell on the 9kv line and we lost the whole block.

not sure.

-John

__________________
2009 Kia Sedona
2009 Honda Odyssey EX-L
12006 Jetta Pumpe Duse
(insert Mercedes here)

Husband, Father, sometimes friend =)