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bz bz is offline
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Default O.T. Step Potential ...

"Arfa Daily" wrote in
:

We'll also take it that this could be largely round, and very
gentle if you were in an open field, and might be far from round and
steep in particular directions towards nearby 'good' grounds in an urban
area. Further, the gradient might be linear, and might not, depending on
ground conductivity in any direction between the point of contact, and
inert ground potential. Sound a reasonable analysis ?


Yes.

Go out in your yard and drive two screwdrivers into the ground 1 foot
apart.
Measure the resistance between them.

Picture a 40 kV line touching earth at some point.
calculate the resistance of concentric rings.

Keep in mind the fact that 'ohms per square' is a useful concept:
A square resistor of ANY dimensions, made of the same material(and same
thickness), will have the same resistance.
This may seem odd, but if you picture putting more resistors in series
(making it longer) at the same time that you put more in parallel (making
it wider), you will see why it is true.

Anyway, you should be able to calculate the voltage gradient around that 40
kV grounding to YOUR soil and then see how far apart two bare feet would
need to be for you to get electrocuted at various distance from the
grounding.





--
bz

please pardon my infinite ignorance, the set-of-things-I-do-not-know is an
infinite set.

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