I have a particular device that I would like to test, which is called
a "thumper". It was made by associated research (model 8613) and is
comprised of two under-desk-refrigerator-sized pieces, about 600 lbs
For those who do not know, a thumper is a device that delivers pulses
of high voltage (up to 25 kV DC in my case) and huge currents, usually
above 1000 joules energy, to a buried high voltage cable where an
insulation fault needs to be located to find out where to dig to
splice it. The lineman walks along the cable path until he feels
"thumps" under his feet from electrical discharges in the faulty
There are warnings on my thumper that say in big letters that it must
be grounded to a ground rod. For obvious usual reasons. I do not want to
ground it to my house ground rod for safety reasons. So I went to Home
Depot and bought their 5/8" 10' "copper clad" ground rod.
What I would like is to achieve two goals with this:
First is to ground the thumper to test it.
The second is to use this rod later for lightning protection. My house
is on top of a modest hill and was already hit by lightning. See
So later on I could save some $$ on needing to install a ground rod
So, my thinking is, the second ground rod would go in the ground close
to the first rod, maybe 2-4 feet or so distance. It would be close to
where other electricals are located and would be in the area that
would be convenient for connecting to some lighting rod to be
installed in the future.
Is that a sensible plan in light of wanting to use that second rod for
How to drive this ground rod. I have a decent compressor and a cheap
"medium" air hammer. Would I be able to drive it in my clay soil? I
read somewhere a suggestion to dig a small hole and fill it with
water, which would then liquefy the soil under air hammer's
pounding. Is that really helpful? How to actually angage an air hammer
to a ground rod?
15 years ago