>there's only one insulator on the top of the transformer
Yes, that is common.
>imagine what would happen if the #6 bare copper line running down the pole in to the ground was CUT! primary voltage at your finger tips.. i DOUBT this is likley.
The situation you describe is not as bad as if the poco grounded conductor were broken for a transformer primary wired to the poco grounded conductor.
I guess you are saying that the center tap (X0) of the secondary would be in series with the now otherwise ungrounded end of the primary (P2).
Cut the ground wire on the pole and it is still grounded at the service.
But for a system relying on the poco grounded conductor, the ground on the pole and at the service are presumed neglible.
The real answer is that current can't flow in two directions at the same time through the transformer.
The is no complete circuit.
First let's consider the set up with no magnetic field. In this case, X0, X1, and X2 all have the same potential. Even if that is primary voltage, it obviously has nowhere to go. So the measured voltage to ground or anything else is zero.
If it is not, then a magnetic field will arise in the primary and secondary coils. Say that the tranformer is a 16 to 1 step down.
Now look at the circuit with the magnetic fields standing. In order for energy to flow from P1 to P2, it must pass by X0. To the extent that it goes into the earth, 16 times as much current can flow between X1 and X2 at 1/16th the voltage -- as expected.
However, to get primary voltage to your finger tips, it must somehow travel from X0 to X1 or X2. Let's suppose that somehow it manages to get to X1. Where can it go next? It is already the same potential as X0, so it can't flow there. If it tries to flow to X2, it has to flow from X2 to X0. But it can't flow from and to X0 simultaneously. So the path is shaped like a "6". It's a dead end. There is no way to get primary voltage into the house through an undamaged transformer. Aren't we lucky?
>they said it faulted about once a week...
What kind of fault? A lightning strike?
That seems likely. But the kind of fault that requires dispatching a repair crew and digging up the wire seems unlikely.
Do you know who "they" are?
[This message has been edited by Dspark (edited 10-05-2001).]
