DIY Home Improvement Forum banner
1 - 13 of 13 Posts

·
Registered
Joined
·
4 Posts
Discussion Starter · #1 ·
I have a subpanel that is wired with 6-3 and no ground. I understand the code changes and why its important to add the ground directly back to the main. My question is this. Can I add a SEPERATE #14 green sheathed wire back to the main or does it have to be ran with the existing 6-3. Additions have been added since this was originally done and it is not possible to run the ground next to the original wire. What is the max distance away from the supply if any that I can run the ground.
 

·
Registered
Joined
·
32 Posts
#14 is way to small. What amperage is the breaker supplying the subpanel. Is there EMT from the main panel to subpanel? If so that is a ground just make sure all connections a tight.

Sent from my XT1097 using Tapatalk
 

·
Registered
Joined
·
4 Posts
Discussion Starter · #3 ·
#14 is standard on #6 wire - see any spec sheet our your local box store. Amps don't matter as I stated it's #6 wire but it's 50 amp. #6 wire is for up to 55 amp allowing a 60 amp breaker. There is no EMT as its residential and almost never used in residential. If there was EMT I would be able to pull the wire and add the ground to it. Also using EMT as a ground is bad practice. The NEC code states the ground needs a direct path back to the main panel.

Thanks for trying to answer anyway.
 

·
Super Moderator
Joined
·
16,893 Posts
Also using EMT as a ground is bad practice. The NEC code states the ground needs a direct path back to the main panel.
Using a metallic conduit as a ground is recognized by the NEC. It is not a bad practice.

The ground in a #6 cable should be #10, not #14.
 

·
Registered
Joined
·
4 Posts
Discussion Starter · #5 ·
#14
But this still doesnt answer my question
Direct from Souther Wire
http://www.southwire.com/ProductCatalog/XTEInterfaceServlet?contentKey=prodcatsheet242

(AWG)/Number of
Conductors
Strands Ground
Wires
Insulation
Thickness
Nom.(mils)
Jacket
Thickness
(mils)
Nom.
O.D.
(mils)
Ampacity * Approx. Net
Weight Per 1000'
(lbs.)
Size Strand Grd Wire Insulation etc
14/3 19 3 x 18 30 45 379 20 ** 107
12/3 19 3 x 16 30 45 420 25 ** 149
10/3 19 3 x 14 30 45 470 30 ** 211
8/3 19 3 x 14 45 60 630 40 328
6/3 19 3 x 14 60 60 794 55 486
4/3 19 3 x 12 60 80 939 70 733
2/3 19 3 x 12 60 80 1071 95 1019
All Bus Drop Cable is constructed with stranded conductors, PVC insulation, cabled conductors, PVC jacket.
*Ampacities are from Table 310.16 in the NEC.
**Unless specifically permitted in 240.4(E) through (G) in the NEC, the overcurrent protection shall not exceed 15 amps for 14 AWG, 20 amps for 12 AWG, and 30
amps for 10 AWG after any correction factors have been applied.
B
 

·
Registered
Joined
·
32 Posts
Disagree with me all u want but the NEC says otherwise and if I remember right #8 is the smallest on #6 but if you had a larger breaker i was going to suggest a #6 which is why I was wonder what size the breaker was.

Sent from my XT1097 using Tapatalk
 

·
Electrician (Retired)
Joined
·
111 Posts
#14
But this still doesnt answer my question
Direct from Souther Wire
http://www.southwire.com/ProductCatalog/XTEInterfaceServlet?contentKey=prodcatsheet242

(AWG)/Number of
Conductors
Strands Ground
Wires
Insulation
Thickness
Nom.(mils)
Jacket
Thickness
(mils)
Nom.
O.D.
(mils)
Ampacity * Approx. Net
Weight Per 1000'
(lbs.)
Size Strand Grd Wire Insulation etc
14/3 19 3 x 18 30 45 379 20 ** 107
12/3 19 3 x 16 30 45 420 25 ** 149
10/3 19 3 x 14 30 45 470 30 ** 211
8/3 19 3 x 14 45 60 630 40 328
6/3 19 3 x 14 60 60 794 55 486
4/3 19 3 x 12 60 80 939 70 733
2/3 19 3 x 12 60 80 1071 95 1019
All Bus Drop Cable is constructed with stranded conductors, PVC insulation, cabled conductors, PVC jacket.
*Ampacities are from Table 310.16 in the NEC.
**Unless specifically permitted in 240.4(E) through (G) in the NEC, the overcurrent protection shall not exceed 15 amps for 14 AWG, 20 amps for 12 AWG, and 30
amps for 10 AWG after any correction factors have been applied.
B

My friend, the example you're giving here from Southwire is for "Bus Drop" cable not NM-B. If you look at the PDF chart for the ground wire it states 3 x 14 which means there are 3 #14 gauge conductors within the cable and when twisted together will be the equivalent of at least a #10.

I'm sure you DON'T have Bus Drop feeding your panel.

So the long and short of this is, if you need a ground for that sub #10 is the size your going to need.
 

·
Super Moderator
Joined
·
16,893 Posts
Disagree with me all u want but the NEC says otherwise and if I remember right #8 is the smallest on #6 but if you had a larger breaker i was going to suggest a #6 which is why I was wonder what size the breaker was.

Sent from my XT1097 using Tapatalk
Please cite the code article that says EMT cannot be used aa a grounding means,

I will save you the time, you will not find it.
 

·
Civil Engineer
Joined
·
5,832 Posts
This topic came up a few times before on this forum. As I recall, strict code interpretation is that the equipment ground wire has to be part of the cable assembly, and cannot be run separately. Unless you are running through conduit, in which case you can (and normally do) pull all conductors and the ground separately. Unfortunately I cannot cite the code section, and I am not certain if there are exceptions, hopefully one of the electricians knows the answer.
 

·
Electrician (Retired)
Joined
·
111 Posts
EMT is very well noted as being a grounding means. Providing it is a complete system derived from the source. The most important thing is making sure all your fittings are tightened securely for the integrity of the system being installed. Although I have installed systems this way my preference is to pull a ground wire with the circuit. That will pretty much alleviate any failure of integrity of the system.
 

·
Registered
Joined
·
4 Posts
Discussion Starter · #12 · (Edited)
My friend, the example you're giving here from Southwire is for "Bus Drop" cable not NM-B. If you look at the PDF chart for the ground wire it states 3 x 14 which means there are 3 #14 gauge conductors within the cable and when twisted together will be the equivalent of at least a #10.

I'm sure you DON'T have Bus Drop feeding your panel.

So the long and short of this is, if you need a ground for that sub #10 is the size your going to need.
It DO HAVE bus drop feeding my panel. I can supply a picture if needed.
Correct 3-#14 guage
Thank you for your answer
 
1 - 13 of 13 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top