Mike Dolt Enterprises
Mike Dolt Enterprises
User: mphillipps, Location: Henrico County, VA
Asked on: Sunday, April 3, 2011 at 5:33 pm EDT
Answered on: Tuesday, May 14, 2024 at 3:42 am EDT
Question: I'm running #4 awg 250' from a service entrance to a new sub panel. Both panels will be properly grounded and bonded. Will I need to run a ground wire the entire 250' from panel to panel or will the ground electrodes at both ends be sufficient?I've spent some trying to looking in the NEC but did not come up with anything specific.A NEC reference be great.
NEC Reference
[250.24(A)(1)](https://codes.iccsafe.org/content/NEC2020/chapter-250#25024A1)
Answer
You do not need to run a ground wire the entire 250' from panel to panel.
The ground electrodes at both ends (the service entrance and the subpanel) are sufficient to establish a grounding path. This is because the following conditions are met: The service entrance panel is properly grounded and bonded. The subpanel is properly grounded and bonded. The grounding electrodes at both ends are connected to the grounding electrode system.In this scenario, the grounding path for the grounding conductor is established through the connection between the service entrance ground electrode and the grounding electrode at the subpanel. The ground wire running the 250' between the panels is not required.However, it is important to note that the grounding conductor must still be installed per the NEC requirements for size and connection to the panel ground bars. Flag for review