supplemental grounding electrode- bonding

[powermac36]

supplemental grounding electrode- bonding

When installing the grounding system for a 200 ampere, 120/240 v, 1-phase service can the installer run a #4 CU grounding electrode conductor through the ground rod to the main water service? I reference artice 250 part III-grounding electrode system and conductor...your help would be appreciated.

 

[johndeereman]

Re: supplemental grounding electrode- bonding

Re: supplemental grounding electrode- bonding

Yes.

 

[bphgravity]

Re: supplemental grounding electrode- bonding

Re: supplemental grounding electrode- bonding

The installtion will most likely require 2 ground rods.

 

[powermac36]

Re: supplemental grounding electrode- bonding

Re: supplemental grounding electrode- bonding

I believed that you could-but why 2-ground rods?

 

[iwire]

Re: supplemental grounding electrode- bonding

Re: supplemental grounding electrode- bonding

Originally posted by powermac36:
why 2-ground rods?

250.56 Resistance of Rod, Pipe, and Plate Electrodes.

A single electrode consisting of a rod, pipe, or plate that does not have a resistance to ground of 25 ohms or less shall be augmented by one additional electrode of any of the types specified by 250.52(A)(2) through (A)(7). Where multiple rod, pipe, or plate electrodes are installed to meet the requirements of this section, they shall not be less than 1.8 m (6 ft) apart.

You have two choices;

Prove that the one rod you install has a resistance to ground of 25 ohms or less.

Or

Install a second rod and forget about testing / proving a resistance to ground of 25 ohms or less.