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When a live/hot wire touches the Earth ground, it creates step voltage and so it's dangerous to walk on ground during this fault. But in a single-wire earth-return system, we use earth/soil as conductor. So why isn't a SWER system dangerous? Even Wikipedia says that "Power engineers experienced with both SWER and conventional power lines rate SWER as equally safe".

I think this question is closely related to the following: In the US split-phase system used in homes, why isn't it dangerous to walk on ground, if a live/hot wire is grounded (and so now it's called the grounded/neutral wire) and thus there should exist a step voltage.

Is it because in order to have a step voltage, we need both wires to be grounded?

(Note: I don't know much nor I have experience with SWER systems and step voltages, so I may be thinking incorrectly something.)

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Naively calculated: The Step-Voltage is basically voltage-difference divided by the distance of the two connection points to earth multiplied by your step with.

So we're normally talking quite big distances and quite low voltage differentials. Additionally, we have a lot of stuff that's better conducting than your skin. Like metallic water pipes in the ground, wet soil and other stuff. So in a working SWER system there is not much danger to humans.

But SWER systems (like they are often used on electric roadcars and railways) can be bad for water pipes. Especially if the systems run on DC. Than you can get corrosion from the current on metallic pipes.

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