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Potential Gradient During Fault to Ground

Potential Gradient During Fault to Ground

Potential Gradient During Fault to Ground

I'm looking for a few drawings that clearly indicate the potential gradient along the earth during a fault to ground. I've come across a few on Google Images, but nothing that's really clear.

I hope to find something that shows a phase conductor contacting the Earth and the voltage gradient from this point back to the transformer neutral. A vertical section view of the earth at depth would be helpful.

Also, what does the gradient look like if a live wire is submerged in water? For example, if a conductor falls into a lake and someone is in the lake, is the gradient across that person's body sufficient to cause death? If the water is conductive, does it energize the entire body of water at a similar potential with the major gradient beginning on land back towards the transformer neutral direction?

RE: Potential Gradient During Fault to Ground

Live wire in water? Would expect "water" gradient to have a similar slope to ground gradient that, if I understand it correctly, would have some water resistance factor related to conductivity multiplied by log n with the fault obviously being the point of origin...but I could be wrong, too, as math isn't my strongest suit.

I do have an anecdote about that, though...

Once while at my brother's cottage, went swimming in the lake toward a neighbour's private dock where, as I approached it, I noticed the owner had tie-wrapped a submersible pump to one of the dock's legs.

Only as I got closer did I notice a half-decomposed dead snake coiled tightly around the body of the pump, and my alarm bells had only just begun going off when there must have been a demand for water; I heard the pump start and simultaneously became extremely uncomfortable. Too bad I instinctively tried to swim away, as the low-magnitude fault current flowing through my body half-paralyzed my legs, these being closest to the point of origin; thankfully my arms were not as profoundly affected and I was by the grace of God able to eventually get clear of the gradient field...it is not inconceivable that had it been otherwise my family members would have eventually discovered my corpse when I failed to return in due time.

I don't ever, ever want to go through that again...and believe me, you don't want to either.

Nobody was staying at that cottage at the time, so I told my brother what had happened and asked him to pass the word to the owner the next time he saw him...never heard what came of it.


"As iron sharpens iron, so one person sharpens another." [Proverbs 27:17, NIV]

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