Pole xformer connections

[jtester]

As to what % comes back as stray

I quizzed a couple of my old prof's when I was looking into electric fields and their effect on the public. It seems that the vast majority, greater than 80%, of the return current flows in the neutral on a typical feeder, and less than 20% of the return current flows in the ground. Many times the ground percentage is much less than 20%, with a 3 phase feeder for example.

That being the case, the 3 phases and neutral together would essentially cancel out B field effects at a distance. A thought that is not often considered.

Jim T

 

[quogueelectric]

3 phase

3 phase

I quizzed a couple of my old prof's when I was looking into electric fields and their effect on the public. It seems that the vast majority, greater than 80%, of the return current flows in the neutral on a typical feeder, and less than 20% of the return current flows in the ground. Many times the ground percentage is much less than 20%, with a 3 phase feeder for example.

That being the case, the 3 phases and neutral together would essentially cancel out B field effects at a distance. A thought that is not often considered.

Jim T

Good thought This might explain to me why I sometimes see a counterpoise wire installed above and below ground on some installations it would provide a low impedance path between downgrounds on different phases to cycle between each other with a defined path rather than back to a substation in any direction