[TowerTalk] Ground system

[Jim Lux]

At 01:43 PM 4/30/2004 -0400, K8fu at aol.com wrote:
>Well the unanimous opinion was that horizontal installation of ground rod is
>right up there with trying to get pet rocks to generate offspring.


Except that the regulatory agencies, who do actually analyze this stuff, 
think that horizontal ground rods are just fine.

For instance, page 131 of IEEE Std-142(1991) "IEEE Recommended Practice for 
Grounding of Industrial and Commercial Power Systems" has a table showing 
ground resistances for a variety of configurations, including "buried 
horizontal wire". Later, on pages 133-135, it discusses the advantanges of 
horizontal cable grounds, particularly where the soil is hard and/or of low 
conductivity. Mention is made that several short horizontal conductors may 
be better than a single deep rod because the inductance is lower.

NBS (now NIST) did tests which indicated that the resistance decreased only 
5% when changing burial depth of horizontal rods and strips from 18 inches 
to 36 inches.

There are some recommendations as to depth of burial in places where it 
freezes.

Consider that  UFER ground ("Concrete Encased Electrode) is considered 
fine, and has almost no vertical penetration.


Jim, W6RMK