On 26/12/2017 05:14, Iggy wrote:
replying to George Miles, Iggy wrote:
Yes, you bring unregulated and unwanted electricity into the building
and you may SEVERELY worsen your earthing.

That seems unlikely. You may make little or no improvement, but so long
as you are not disconnecting the existing electrode its not going to get
worse.

Close lightning strikes energize the
earth
and would energize your earth rod. Poor earthing conditions are dry
soil, so
being under the building's footprint could mean little to no earthing
actually
happens.

That really depends on the local soil conditions.

The 3rd rod should NOT be a replacement of the existing 2 and MUST
only be added to the existing 2 by a jumper conductor...ONLY IF
determined to
be needed or beneficial.

The benefit it sounds like the OP is aiming for is that of better
redundancy and fault tolerance, since the connection to the existing
electrode is vulnerable to damage.

(Protecting the existing main connection better would seem prudent also)

This addition or by driving your existing rods deeper, is the ONLY way to
reduce your resistance. But, what is your current resistance? If you're

Multiple rods are ok (and are commonly used in the supply side of PME
installations for example), but ideally don't want to be too close
together such that they are in overlapping resistance areas.

already at very low resistance, then you likely can't make it any better
because you're down to the conductor's own resistance. Don't do anything
unless and until you know what your resistance is. More rods IS NOT
better and

You can't say that with any certainty. More rods "may" not be better -
but then again they might. It will depend on the circumstances and local
soil conditions.

WILL only extend your reach to pick up static electricity, fallen
power-line
or lightning energy...a deeper single rod is factually best.

I suspect if you have a lightening strike or fallen power line *inside*
your property, you have other things to worry about.


--
Cheers,

John.

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