Grouonding a subpanel


Old 12-17-05, 08:23 AM
Thread Starter
Join Date: Dec 2005
Location: USA
Posts: 3,185
Received 1 Vote on 1 Post
Grouonding a subpanel

I've installed a sub panel in my detached garage. It is fed from a 60amp breaker in my house service entrance panel. The sub panel ground and neutral busses are not bonded. I drove an 8' X 5/8" copper rod into the ground and attached it to the sub panel ground bus with AWG 6 copper stranded. How can I tell if this single rod provides an adequate ground for the sub panel?
Sponsored Links
Old 12-17-05, 09:37 AM
HandyRon's Avatar
Join Date: Dec 2001
Location: New York
Posts: 1,365
Received 0 Votes on 0 Posts
You would need a special meter, that is not worth buying. The code permits you to drive a second rod and connect it, then no further integrity testing is required.
Old 12-17-05, 11:03 AM
Visiting Guest
Posts: n/a
ground loop

One thing I would check- if your main panel has its own ground (I am sure) and you are connecting the ground wire between the main and sub, and you provide a ground rod to the sub as well, you could create a ground loop condition. These are bad. In essence - if there are 2 paths to ground for an outlet, say your ground rod on the sub panel, and the ground rod on the main panel, then potential will flow.

I just installed a sub panel for my hot tub - ran 6-3 plus ground, and connected the ground the whole way. So that way there is only one path to ground - no loop.

I am not an electrician, but I used to install large battery backup systems in large datacenters, and the lengths gone to prevent ground loops was staggering. I have even seen a ground halo run around the entire room before - now that was some getup.

Make sure you dont have a possible ground loop condition - real electricians please chime in and beat me up here if I am the least bit off.

Old 12-17-05, 01:06 PM
Join Date: Feb 2002
Location: port chester n y
Posts: 2,117
Received 0 Votes on 0 Posts
The NEC requires a Grounding Electrode at a seperate, detached stucture.

Ground-path concerns arise if the Feeder does not provide an Equiptment Grounding Conductor.
Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Thread Tools
Search this Thread
Ask a Question
Question Title:
Your question will be posted in: