Earth contact resistance

Lee Lumpkin
Wed, 3 May 2000 19:39:59 -0400

Although I don't have an earth mat, I do have 3 widely spaced 3/4 inch
copper ground pipes.  They have 2 small 'weep' holes about every 6
inches along their length, drilled before I drove them down into 1/2
inch holes created by conduit.  The information that I used in setting
this up recommended epsom salts, which I pour into the open top of the
pipe, followed by water.  I cap the pipes between treatments.  (I
forget the chemical makeup, and I'm away from that location for a
year, so can't find or check the reference.  A little voice in my head
keeps whispering 'magnesium salts' as an ingredient.)  The solution
seeps out through the holes in the pipe and creates (theoretically) a
better ground.  I have not done any measurements to test the results.
A chemist may want to comment on this.

My source indicated that epsom salts are harmless to plants, and I've
seen them recommended (and used them) as an additive to lawn
fertilizer for 'greening up' a lawn.  If you're doing a wider area
'earth mat', a fertilizer spreader of the hand cranked style would
work, and you could even mix in some fertilizer while you're at it.


----- Original Message -----
From: Andre' Kesteloot <>
To: lf-amrad <>; AMRAD Tacos <>
Sent: Wednesday, May 03, 2000 7:35 AM
Subject: Earth contact resistance

> Alan Melia wrote:
> > Hi all, I have noted again from Peter's description of the Tesla
> > at the Museum, and from John's Earth Wireless web site, that the
addition of
> > several pounds (or kgms) of common salt (and water) seems to be a
usual way
> > of improving the contact resistance beween earth rods and the
> > ground. It occurs to me that those with an enviromental approach
or just
> > those who are keen gardeners (I note the reluctant pruning near
> > aerials!) might not wish to blight their garden with large
quantities of
> > sodium chloride. I have seen somewhere in radio literature that
Gypsum is
> > almost as good in the electrical parameters and is actually
> > horticulturally. It is much less soluble than salt and for the
same effect
> > will not need quite so many repeated treatments (It may not yield
quite such
> > a low resistance). I suspect its worth a try as Gypsum ( Calcuim
> > is available from most Garden Centres.
> >
> > "I am just top dressing the lawn dear...."      when decreasing
> > resistance of the earth-mat you surreptitiously buried under
> > it.............. It could just be worth an extra helping of
chocolate fudge!
> >
> > Cheers de Alan G3NYK
> >
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