Pole Pig Question
Hey. In my search for a distribution transformer, a couple of questions
came to my mind. First of all, I have observed that single-phase
transformers only have one high voltage terminal, while triple-phase
transformers have two. Aside from that, what are differences? (I guess
I'm asking for the theory behind the different phases of AC current.)
Also, some of the transformers have primary voltages that I can understand.
For example, 12470 volts. Others have weird things like 7200/12470Y, or
12470GY/7200. Could you please explain this to me also? I have a feeling
it has to do with the 1-phase and 3-phase thing, but I don't know.