"Ignoramus22371" wrote in message
...
On Sat, 16 Dec 2006 02:15:56 +0000, Ian Malcolm
wrote:
I would personally want the test ground rod an order of magnitude of its
length away from the house, under ground utilities, neibouring buildings
etc. I also reccomend you wear rubber boots while testing as under high
voltage fault conditions significant potentials can be developed over a
fairly short distance at the soil surface for some soil types and
moisture levels. Unless the bulk resistivity of your soil is extremely
low, you will get significant coupling between rods seperated by one
rods length. Try 50 to 200 feet away from any structures. If you must
drive the rod near the house, disconnect all electronic appliances in
the house from all signal and power cables before you start testing.
From the specs you have given, if you are too close to it, the thumper
is easily capable of causing ground transients comparable to a nearby
lightning strike.


Ian, thanks. You gave me some good reasons to pound the rod away from
other rod. Also, I will control the thumper with something insulating,
like a dry wooden board, and will use minimal voltages (like 5 kV
instead of 25 kV). I may also stand on a plastic bucket just in case.


i

The IEEE Green Book recommends one ground rod length. That is where I got
it.