[TowerTalk] Another Grounding Question

[Jim Brown]

On 9/6/2012 8:44 PM, Gary "Joe" Mayfield wrote:
> There is no obvious ground rod to be seen.

Don't ignore the possibility that there is none, or that it's buried 
somewhere.  Many  electricians are better carpenters than technicians, 
and their technical training is often weak.

NEC (and good engineering practice) require that there be a ground 
connection AT THE SERVICE ENTRANCE (that is, at the first electrical 
enclosure in your home after the meter.  Grounds may be ADDED, but that 
one is required.

What usually comes from the power company through the meter to our homes 
is three wires 120-0-120. That is, both sides of center-tapped 240V 
transformer, plus the center tap, which is the Neutral.  While the 
neutral is grounded by the power company at various points in their 
distribution system, that ground is for lightning protection, and is not 
intended to carry current.  Only two sides of 120V and the neutral 
should carry current.

I've seen some real messes, including the house I bought here in 
California. The biggest goof -- there was no "ground rod," instead the 
panel was "grounded" to a hose outlet about 40 ft away from the panel, 
and that hose outlet was connected to PVC pipe.  In other words, there 
was no earth connection.

73, Jim K9YC