[TowerTalk] Peripheral ground system

[Guy L. Olinger]

Barry Kutner wrote:
> 
> On 11 Jun 98, Pete Smith <n4zr@contesting.com> wrote:
> 
> > More to the point, what does the frost line have to do with buried wire,
> > anyway?  If you don't bury radials that deep, why would you have to do so
> > with a perimeter ground wire?  For that matter, all of my feed and control
> > lines come across the lawn in two runs of PVC conduit, which is buried only
> > about 3 inches deep, and it has stayed put so far through one very hard
> > winter and two average ones.
> >
> > Am I missing something?
> >
> Good question, Pete. In theory, the idea of going below the
> frost line is to prevent heaving of whatever is buried, so it doesn't
> reappear at the surface some day, from earth movement of the
> freeze/thaw cycles. For that reason, my conduit was buried about 2 1/2
> ft (frost line abt 18 inches here).
> 

Heaving is bad, real bad.

First, if it occurs unevenly (highly probable), it can put enormous
strain on conductors and connections, breaking conductors and pulling
wires out of connectors or worse.

Second, it disturbs the contact between straps (or whatever) and ground,
making the overall result far less conductive, making the installer's
sense of security rather false.

This isn't that much of a consideration down here in eastern Nawth
Cahralina y'all, but when I lived in Putnam County, NY, we had water
pipes freeze down four feet (even though the code freeze line was three
feet).

By the way, someone was talking about putting the grounds next to (or
in?) the foundation french drain. Bad, bad, bad... Need to get out into
the good ole dirt. Often times the stuff next to the french drain is
stones, busted bricks & construction debris buried in place rather than
being hauled off, very poor conduction.

KNOW where all the stuff coming into the house is, dig up these areas
carefully by hand first until you've located them all, then get a
ditchwitch and go for it.

73, y'all.

Guy.

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