Multiple system ground rods

I have always understood the code to mandate only one system ground at the point of first overcurrent protective device. Recently a new electrical inspector began doing our inspections. In the following example he is requiring a second ground electrode and I believe he is wrong. Please clarify and help me understand the reasoning. The installation involves a combination meter/disconnect with a main breaker. We have always grounded the system at that point and carried the ground downstream through the 4th wire. Now the new inspector has required us to add an additional ground electrode at the remote panel location. Is this correct? And if so why?
 

Little Bill

Moderator
Staff member
Location
Tennessee NEC:2017
Occupation
Electrician
I have always understood the code to mandate only one system ground at the point of first overcurrent protective device. Recently a new electrical inspector began doing our inspections. In the following example he is requiring a second ground electrode and I believe he is wrong. Please clarify and help me understand the reasoning. The installation involves a combination meter/disconnect with a main breaker. We have always grounded the system at that point and carried the ground downstream through the 4th wire. Now the new inspector has required us to add an additional ground electrode at the remote panel location. Is this correct? And if so why?
If the remote panel is on/in the same building he is incorrect.
If it is in/on a separate building/structure he is correct.
 

petersonra

Senior Member
Location
Northern illinois
Occupation
engineer
I have always understood the code to mandate only one system ground at the point of first overcurrent protective device. Recently a new electrical inspector began doing our inspections. In the following example he is requiring a second ground electrode and I believe he is wrong. Please clarify and help me understand the reasoning. The installation involves a combination meter/disconnect with a main breaker. We have always grounded the system at that point and carried the ground downstream through the 4th wire. Now the new inspector has required us to add an additional ground electrode at the remote panel location. Is this correct? And if so why?
I think he could be right. Is the meter on some kind of structure like a pole?
 

mwm1752

Senior Member
Location
Aspen, Colo
It is the Main Service to only one building
Service Equipment. The necessary equipment, usually consisting of a circuit breaker(s) or switch(es) and fuse(s) and their accessories, connected to the load end of service conductors to a building or other structure, or an otherwise designated area, and intended to constitute the main control and cutoff of the supply.
Service Conductors. The conductors from the service point to the service disconnecting means.

So is the first point of disconnect for the service not on the structure of the remote panel ?
 

mwm1752

Senior Member
Location
Aspen, Colo
The combination meter/disconnect is mounted on a 6x6 stub pole and is remote from the only building it feeds. The utility feed comes in underground, feeds the meter/disconnect, then the 4 wire feed goes out to a single panel in the building.
Inspector is correct on a separate grounding system for structure which will bond to non current carrying metal & conductors only.
 
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