250.52(A)(4)

[don_resqcapt19]

3. Proposal (include proposed new wording, or identification of wording to be deleted):

(4) Ground Ring (or Grounding Lateral). A ground ring encircling the building or structure, (or a grounding lateral) in direct contact with the earth, consisting of at least 6.0 m (20 ft) of bare copper conductor not smaller than 2 AWG.

4. Statement of Problem and Substantiation for Proposal:
What is the magic about a ground ring? A 20? copper conductor not smaller than 2 AWG installed as a radial or lateral will perform at least as well as the ground ring encircling the building or structure. The length of the copper in direct contact with the earth is the main factor, not the layout of the copper.

New wording in (xxx)
Don

 

[George Stolz]

Re: 250.52(A)(4)

Good call!

 

[ryan_618]

Re: 250.52(A)(4)

I don't see how the proposed language solves the issue. How about something like:

"At least 6.0 m (20 ft) of bare copper conductor not smaller than 2 AWG in direct contact with the earth."

 

[George Stolz]

Re: 250.52(A)(4)

I guess the way the sentence is structured, it could be construed that a ground ring would not have to be in direct contact with the earth. While it goes without saying, it should be said.

So, this would be more correct.

(4) Ground Ring (or Grounding Lateral). A ground ring encircling the building or structure, or a grounding lateral in any configuration, consisting of at least 6.0 m (20 ft) of bare copper conductor not smaller than 2 AWG in direct contact with the earth.

 

[jwelectric]

Re: 250.52(A)(4)

Try standing in front of 20 to 30 students and explaining how a 20 foot conductor can encircle anything much bigger than a port-a-john