[GreenKeys] Australian Power cords.

[jim at k6ccc.org]

From: "Michael Katzmann
> The curious practice by Pepco (my utility) is they run 13 kV three phase
> without neutral (three lines) on the top of the poles. They have a
> transformer on the pole for every few of houses. The transformer has a
> connection to one phase and one to an earth stake next to the pole. So the
> return is through ground. I would have thought that this would be
> unacceptably lossy but apparently not.

That does seem a bit unusual, but with a good grounding system, you would be surprised what you can do with an earth return.

Here in the western US there are two MegaVolt DC transmission systems.  One from the Los Angeles area to near Bonneville Washington, and the other from the California high desert to Delta, Utah.  Both operate normally with +500KV DC on one wire and -500KV DC on the other wire (1MV wire to wire).  These systems have capacity between 2,400 and 3,100 MegaWatts.  Both of them have the ability to operate with 700KV on one wire and use earth as the return in the event that there is a problem on one of the wires.  I will point out that the ground system is NOT a simple ground rod.

73
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Jim Walls - K6CCC
jim at k6ccc.org