Moist soil is somewhat conductive, or else ground rods would not work. This
being so, there has to be attenuation of the electric field. If significant
fields did exist at the surface, that same conductivity would cause
electric shock to anyone walking on the surface.
The magnetic field would be attenuated a bit by the conductive soil. But
the biggest reduction would probably come about from the installation. My
guess is that all three (insulated) cables were buried in one trench,
rather than three trenches, which is possible to do due to the insulation
around the conductors. This makes for much closer spacing of the
conductors, resulting in better field cancellation and much lower magnetic
fields at reasonable distances away from the conductors.
Don Borowski
Schweitzer Engineering Labs
Pullman, WA
[email protected] wrote on 03/09/2004 09:36:03 AM:
>
>
>
> Hi Robert:
>
>
> > Later the high tension towers have been replaced with
> > underground transission lines as part of the Guadalupe
> > corridor beautification plan.
>
> Hmm. I don't believe burying transmission lines
> attenuates either the magnetic or electric fields.
> Obviously, something must be done to attenuate the
> electric field to prevent shocks above ground due
> to a body crossing too many equipotential lines.
> Attenuating the electric field may or may not also
> attenuate the magnetic field.
>
> Comments on attenuation of electric and magnetic
> fields of buried high-tension lines as compare to
> overhead lines?
>
>
> Best regards,
> Rich
>
>
>
>
>
>
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