Vasile Surducan wrote:
> > In my reading on this subject, rebar in concrete in contact
> > with soil was the absolute lowest ground resistance you
> > could get.
>
> If we use this methode than they shut us !
> A protective ground in Romania ( a third country on the East
> of the Europe) is something much serious than rebar in concrete.
> I believed this methode is not used anywhere...

   Romania is a Central Europe country geographically, have
a look at a map.
   It's hard to believe, Vasile, in some countries concrete
reinforcing bars use to got welded all through building
including basement. This makes perfect well grounded steel
frame.

> > The ability of a 1/2" diameter steel rod to handle
> > mega-currents is tremendous.

Actually Lawrence meant not just one steel rod, but rather
frame of rods, in my opinion.

> We haven't (yet) huge storms here. The protective ground
> here is not for lightings but to protect people when are
> using indoor home electrical devices. An 1/2 steel pipe
> connected with another one of 4 inch and all these having
> more kilometers length may handle anything you want.

Have you ever built water-supply systems, Vasya? Where did
you see pipes of kilometers length? Only hundreds of
6m pipes connected in series to each other by a drunken
worker sometimes. The resistance of a dry connection could
be very high.

"To protect people when are using indoor home electrical
devices" you have to equalize electrical potential of
a device with the potential of walls and floor(recall frame
of rods), not with the potential of some distant ground
kilometers away.

Best wishes,

Mike.

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