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Bob Engelhardt

On 10/18/2019 11:25 AM, wrote:
The top wire is 17,000 volts. The lower is the neutral. Both are tied
to a transformer that feeds my house and one across the street. The
neutral is also tied to a ground at the pole. There is at least one
pole before mine that has a wire going to ground from the neutral. And
yes, I did have 220 while the neutral wire was down.

That's pretty scary, actually. If the ground at the pole was broken, or
marginal, the primary would be grounded by your & your neighbor's
service ground rods. I.e., your service would be part of the 17,000
volt circuit. In the very worst case, if your grounds were broken, you
would have 17,000 volts on your houses' circuits, just waiting for a
path to ground.

----- 17,000 -----) (----- 240 ----
) (___.________ Neutral _____
) ( | |
X Neutral --+-) (---|--240 ---- |
|________| Gnd
|
Gnd

I am amazed that the ground could work so well. Maybe it's because the
ground here is so wet.
Eric

Part of it working so well is that most of the current in one leg
returns through the other leg. It's only the difference that returns
through the ground. E.g., if there were 10 amps of load on 1 leg and 12
on the other, only 2 amps would flow through the ground.