Grounding Conductor For Service Must Be # 4 Copper Wire - Electrical - DIY Chatroom Home Improvement Forum
Advertisement


Go Back   DIY Chatroom Home Improvement Forum > Home Improvement > Electrical

CLICK HERE AND JOIN OUR COMMUNITY TODAY...IT'S FREE!

Like Tree1Likes
  • 1 Post By brric
Reply
 
Thread Tools
Display Modes
Old 04-21-2019, 08:27 PM   #1
Member
 
Join Date: Dec 2015
Posts: 267
Rewards Points: 534
Default

Grounding conductor for service must be # 4 copper wire


This the note that the inspector left when came to inspect the electrical installation on a double wide mobile home.

Can someone please correct me if I am wrong, but I thought # 4 should be for aluminum wire and for copper wire should be # 6 - according to the code book correct?

This is for residential installations.
form8829 is offline   Reply With Quote
Sponsored Links
Advertisement
 
Old 04-21-2019, 09:39 PM   #2
Master Electrician
 
Join Date: Mar 2010
Location: Indiana
Posts: 4,327
Rewards Points: 4,910
Default

Re: Grounding conductor for service must be # 4 copper wire


Service size and type of grounding determines conductor sizing. NEC never requires larger than #6 copper to grounding rods. Local requirements may differ. Never use aluminum conductors for grounding if they are at or below grade.
brric is offline   Reply With Quote
Sponsored Links
Advertisement
 
Old 04-22-2019, 09:43 AM   #3
Member
 
Join Date: Dec 2015
Posts: 267
Rewards Points: 534
Default

Re: Grounding conductor for service must be # 4 copper wire


I guess my other question will be, is the inspector referring to the main conductors from the outside panel to the inside?
form8829 is offline   Reply With Quote
Sponsored Links
Advertisement
 
Old 04-22-2019, 08:36 PM   #4
Member
 
Join Date: Nov 2007
Location: Nashua, NH, USA
Posts: 8,562
Rewards Points: 2,730
Default

Re: Grounding conductor for service must be # 4 copper wire


What was the inspector saying (words verbatim, not asking you to read his mind) when you thought he might be referring to the main conductors from the outside panel to the inside?

Incidentally if there is a panel or box with a whole house shutoff outside under the meter then there must be 4 conductors -- two hots, neutral, and ground -- running from there to any inside panel which may be large and may be the primary panel for the house branch circuits.
__________________
Heat went off in the dead of winter? Excellent idea to be late or absent for work and to spend the day winterizing your house to keep pipes from freezing. Every house is different. For those of you not hit yet, think of what things you need to do.

Last edited by AllanJ; 04-22-2019 at 08:41 PM.
AllanJ is offline   Reply With Quote
Old 04-23-2019, 01:04 AM   #5
Licensed electrician
 
Join Date: Sep 2007
Location: Maryland
Posts: 12,314
Rewards Points: 3,592
Default


What size is the service you are installing? Is the grounding for a metallic water.line or to a rod?
__________________
Answers based on the National Electrical Code. Local amendments may apply. Check with your local building officials.
Jim Port is offline   Reply With Quote
Old 04-23-2019, 05:49 PM   #6
Member
 
Join Date: Dec 2015
Posts: 267
Rewards Points: 534
Default

Re: Grounding conductor for service must be # 4 copper wire


he actually was referring to the conductor that goes to the grounding rods.
form8829 is offline   Reply With Quote
Old 04-23-2019, 08:33 PM   #7
Member
 
Join Date: Nov 2018
Posts: 287
Rewards Points: 58
Default


The ground from the 1st means of disconnect past your meter needs to be #4 copper if it is a 200 amp service (2/0 or 3/0 hot conductors).
Wiredindallas is offline   Reply With Quote
Old 04-23-2019, 09:07 PM   #8
Master Electrician
 
Join Date: Mar 2010
Location: Indiana
Posts: 4,327
Rewards Points: 4,910
Default

Re: Grounding conductor for service must be # 4 copper wire


Quote:
Originally Posted by Wiredindallas View Post
The ground from the 1st means of disconnect past your meter needs to be #4 copper if it is a 200 amp service (2/0 or 3/0 hot conductors).
Not to grounding rods per NEC.
jhil likes this.
brric is offline   Reply With Quote
Old 04-25-2019, 02:36 PM   #9
Member
 
Join Date: Jan 2019
Posts: 183
Rewards Points: 362
Default

Re: Grounding conductor for service must be # 4 copper wire


Quote:
Originally Posted by brric View Post
Not to grounding rods per NEC.

Per the NEC it depends on the size of the service-entrance conductor. Safer to go with 4 AWG wire as the cost difference is trivial at less than 40 cents a foot in savings.

Where I use 6-gauge is when I need to bridge a valve or water filter put in a jumper wire to maintain the ground continuity of copper pipe.
Calson is offline   Reply With Quote
Old 04-25-2019, 05:21 PM   #10
Master Electrician
 
Join Date: Mar 2010
Location: Indiana
Posts: 4,327
Rewards Points: 4,910
Default

Re: Grounding conductor for service must be # 4 copper wire


Quote:
Originally Posted by Calson View Post
Per the NEC it depends on the size of the service-entrance conductor. Safer to go with 4 AWG wire as the cost difference is trivial at less than 40 cents a foot in savings.

Where I use 6-gauge is when I need to bridge a valve or water filter put in a jumper wire to maintain the ground continuity of copper pipe.
Another incorrect statement. The NEC does not require larger than #6 copper to grounding rods, regardless of the service size. Upsizing provides no additional protection.

Last edited by brric; 04-25-2019 at 05:24 PM.
brric is offline   Reply With Quote
Old 04-25-2019, 09:59 PM   #11
Licensed electrician
 
Join Date: Sep 2007
Location: Maryland
Posts: 12,314
Rewards Points: 3,592
Default


Quote:
Originally Posted by Calson View Post
Quote:
Originally Posted by brric View Post
Not to grounding rods per NEC.

Per the NEC it depends on the size of the service-entrance conductor. Safer to go with 4 AWG wire as the cost difference is trivial at less than 40 cents a foot in savings.

Where I use 6-gauge is when I need to bridge a valve or water filter put in a jumper wire to maintain the ground continuity of copper pipe.
The #6 to bond over a meter is not large enough on a water line ground.

The NEC never requires anything larger than #6 to a ground rod. You are not getting any additional safety by using #4.
__________________
Answers based on the National Electrical Code. Local amendments may apply. Check with your local building officials.
Jim Port is offline   Reply With Quote
Sponsored Links
Advertisement
 
Reply


Thread Tools
Display Modes

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


Similar Threads
Thread Thread Starter Forum Replies Last Post
Digitial Timer in 3 Gang box with (2) 3way switches and 1 single pole..confused. BCS Electrical 33 03-20-2016 11:30 PM
House grounding wire near/touching gas pipe. Safe? CardCoder502 Electrical 20 01-10-2014 05:03 PM
yet another 3 wire range hookup question - grounding receptacle plate/box? rkg Electrical 7 04-03-2012 01:02 AM
Need to know if my grounds and neutrals are connected right dorlow Electrical 185 01-15-2012 02:54 PM
hooking up dryer....bronx ny code SURFBUG Appliances 6 10-14-2008 09:41 PM




Top of Page | View New Posts