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

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

Reply
 
Thread Tools Search this Thread Display Modes
Old 02-17-2011, 01:26 PM   #1
him
Newbie
 
Join Date: Feb 2011
Location: Pittsburgh, PA
Posts: 7
Share |
Default

Yet Another 3-Pronged Dilemma


I hate two-prong outlets. I have one in a box that is cemented in the wall with no access to the type AC (armored cable) feeding it. (It used to be a fireplace.) Among the thousands of threads I have read it was said that one should not depend on the armor as a ground conductor. However NEC 2011 250.118(8) seems to indicate that it is acceptable. But maybe the cable I have is not up to current standards. Comments?

Let's assume the armor is unacceptable and I can somehow run a ground wire up and into to box. Is it acceptable to run this wire (green insulated 12 gauge) to any other adequately sized (i.e. in this case 15A) ground? Or does that ground wire have to follow the supply circuit back to the subpanel for termination?

him is offline   Reply With Quote
Old 02-17-2011, 04:46 PM   #2
Member
 
Join Date: Nov 2007
Location: Nashua, NH, USA
Posts: 6,864
Default

Yet Another 3-Pronged Dilemma


The ground wire from your newly to-be grounded receptacle must go back to the panel more or less following the route of the supply circuit cable. But if the new ground wire should reach the fat ground wire (grounding electrode conductor) between the panel and the entering cold water pipe (or a ground rod) first then the ground wire can stop there.

__________________
Stop wasting time re-adjusting the pattern. Have several lawn sprinklers, one for each pattern.

Last edited by AllanJ; 02-17-2011 at 04:52 PM.
AllanJ is offline   Reply With Quote
Old 02-17-2011, 07:56 PM   #3
Member
 
Join Date: Jul 2008
Location: Canada (s/w ON.)
Posts: 2,294
Default

Yet Another 3-Pronged Dilemma


It depends on the jurisdiction! In my area the ground can be picked up from a water pipe.
Wildie is offline   Reply With Quote
Old 02-18-2011, 11:24 PM   #4
him
Newbie
 
Join Date: Feb 2011
Location: Pittsburgh, PA
Posts: 7
Default

Yet Another 3-Pronged Dilemma


My municipality has adopted the Uniform Construction Code of PA. I don't know if that has anything to do with wiring.

I was happy to be able to read the NEC online simply by signing up with the NFPA. Allan, just for my edification, can you site the approximate location in the code where it says follow the supply circuit cable? I couldn't find anything about it.

Thanks to all for your replies.
him is offline   Reply With Quote
Old 02-19-2011, 07:09 AM   #5
Member
 
Join Date: Nov 2007
Location: Nashua, NH, USA
Posts: 6,864
Default

Yet Another 3-Pronged Dilemma


Quote:
Originally Posted by him View Post
Allan, just for my edification, can you site the approximate location in the code where it says follow the supply circuit cable? I couldn't find anything about it.
It doesn't have to follow exactly; for example if you don't want to break open the walls and the outlet is on an exterior wall then you could drill a small hole to the outside and run the ground wire under the edge of a clapboard and at an appropriate location, down and into a small hole in a rim joist.

I don't have the code chapter and verse handy but that has been paraphrased more than once on this forum including such things as "to a point on the grounding electrode system".

The grounding electrode system consists of three parts: (1) a ground rod, or an underground metal water pipe entering the building, (2) a continuous (nonstop; home run) copper wire of minimum specified size (#6 for 100 amp or smaller services) and (3) the connection point of #2 to the service neutral including an appurtenant terminal strip or bus bar, in the panel.

Specifically mentioned was the panel (could be a subpanel) where the corresponding circuit cable enters.

Local codes may define additional points, such as water pipes going upstairs, to which something may be connected to and then be considered bonded for grounding purposes.
__________________
Stop wasting time re-adjusting the pattern. Have several lawn sprinklers, one for each pattern.

Last edited by AllanJ; 02-19-2011 at 07:25 AM.
AllanJ is offline   Reply With Quote
Old 02-19-2011, 11:07 AM   #6
Scared Electrician
 
Saturday Cowboy's Avatar
 
Join Date: Nov 2009
Location: Colorado
Posts: 715
Default

Yet Another 3-Pronged Dilemma


see code sections 250.130 (c) and 406.3(D)
__________________
Ragged Trousered Philanthropist


Please follow the code - its there for your safety no matter how inconvenient.
Saturday Cowboy is offline   Reply With Quote
Old 02-19-2011, 07:48 PM   #7
Newbie
 
Join Date: Feb 2011
Posts: 18
Default

Yet Another 3-Pronged Dilemma


you can connect to any other ground wire of at least the same size.
jadbad2004 is offline   Reply With Quote
Old 02-19-2011, 08:43 PM   #8
UAW SKILLED TRADES
 
Stubbie's Avatar
 
Join Date: Jan 2007
Location: Kansas
Posts: 4,875
Default

Yet Another 3-Pronged Dilemma


Quote:
Originally Posted by jadbad2004 View Post
you can connect to any other ground wire of at least the same size.
No you cannot connect to just any ole 'ground wire' of the same size. The NEC is specific about the points where an added egc may terminate. None of which is another ground wire of the same size.

The code articles were given by Saturday Cowboy.
__________________
" One nice thing about the NEC articles ... you have lots of choices"

Stubbie
Stubbie is offline   Reply With Quote
Old 02-19-2011, 08:56 PM   #9
Newbie
 
Join Date: Feb 2011
Posts: 18
Default

Yet Another 3-Pronged Dilemma


Quote:
Originally Posted by Stubbie View Post
No you cannot connect to just any ole 'ground wire' of the same size. The NEC is specific about the points where an added egc may terminate. None of which is another ground wire of the same size.

The code articles were given by Saturday Cowboy.
you are correct, it must be of the same branch circiut, I stand corrected on that but you can connect to any ole ground wire on the same branch circiut.
jadbad2004 is offline   Reply With Quote
Old 02-19-2011, 09:04 PM   #10
" Euro " electrician
 
frenchelectrican's Avatar
 
Join Date: Apr 2006
Location: WI & France { in France for now }
Posts: 5,369
Default

Yet Another 3-Pronged Dilemma


Quote:
Originally Posted by jadbad2004 View Post
you are correct, it must be of the same branch circiut, I stand corrected on that but you can connect to any ole ground wire on the same branch circiut.
That part is true however for olÚ grounding conductour it will depending on how well it is before you can make a judgement call on this one.

Merci.
Marc
__________________
The answer will be based on NEC ( National Electrical code ) or CEC ( Cananda Electrical code ) or ECF ( Electrique Code France )
frenchelectrican is offline   Reply With Quote
Old 02-19-2011, 09:13 PM   #11
Newbie
 
Join Date: Feb 2011
Posts: 18
Default

Yet Another 3-Pronged Dilemma


Quote:
Originally Posted by frenchelectrican View Post
That part is true however for olÚ grounding conductour it will depending on how well it is before you can make a judgement call on this one.

Merci.
Marc
AS i said ealier in simple terms, same size wire or lager. NEC says grounding con ductor must be able towithstand the entire circiut load ie 20 amp breaker = ground wire must be sized to handle that much current.. There is no judgement call if it is on the same branch circiut because the overload/short circiut protection will be one in the same as the groungind conductor you tap. And something for all of us to remember is that the NEC is the bare minimum of what we are permitted to do. With that said an unbroken ground from point of use to the grounding bad is always the best but usually not practical.

Last edited by jadbad2004; 02-19-2011 at 09:18 PM.
jadbad2004 is offline   Reply With Quote
Old 02-19-2011, 09:22 PM   #12
" Euro " electrician
 
frenchelectrican's Avatar
 
Join Date: Apr 2006
Location: WI & France { in France for now }
Posts: 5,369
Default

Yet Another 3-Pronged Dilemma


Jadbad.,

I understand what you are refering to this however did you see old style NM cable with reduced grounding conductor size in there before ??

Few of us in this forum allready see it before. { I have see in both North Americian and European verison so I did see both ways }

Merci.
Marc
__________________
The answer will be based on NEC ( National Electrical code ) or CEC ( Cananda Electrical code ) or ECF ( Electrique Code France )
frenchelectrican is offline   Reply With Quote
Old 02-19-2011, 09:29 PM   #13
Newbie
 
Join Date: Feb 2011
Posts: 18
Default

Yet Another 3-Pronged Dilemma


Quote:
Originally Posted by frenchelectrican View Post
Jadbad.,

I understand what you are refering to this however did you see old style NM cable with reduced grounding conductor size in there before ??

Few of us in this forum allready see it before. { I have see in both North Americian and European verison so I did see both ways }

Merci.
Marc
Yes I have seen smaller ground conductor which is common and acceptable refer to NEC talble 250.122 and that is also why I said ground conductor needs to be same size or larger than the one being tapped. (assuming original calculations on existing system was correct)
jadbad2004 is offline   Reply With Quote
Old 02-19-2011, 09:33 PM   #14
UAW SKILLED TRADES
 
Stubbie's Avatar
 
Join Date: Jan 2007
Location: Kansas
Posts: 4,875
Default

Yet Another 3-Pronged Dilemma


Quote:
Originally Posted by jadbad2004 View Post
you are correct, it must be of the same branch circiut, I stand corrected on that but you can connect to any ole ground wire on the same branch circiut.
HUH?

How can you connect to the equipment ground wire on the same branch circuit when there isn't one? The op is asking if he doesn't have an egc in the branch circuit can he run a seperate ground wire.

To answer the op's question you would refer to the code articles Saturday Cowboy posted. You can run an egc to any of those places any how you want to get there...or you can install a gfci receptacle.
__________________
" One nice thing about the NEC articles ... you have lots of choices"

Stubbie
Stubbie is offline   Reply With Quote
Old 02-20-2011, 08:44 AM   #15
A "Handy Husband"
 
rjniles's Avatar
 
Join Date: Feb 2007
Location: South Carolina Low Country
Posts: 3,939
Default

Yet Another 3-Pronged Dilemma


Not sure of the OP's statement that he hates 2 wire receptacles, is he worried about personnel safety or does he need to plug in a 3 wire plug?

If the ground is not needed for electronic equipment protection, why not install a GFCI? This would give personnel protection and allow the use of 3 wire plugs without an adapter.

__________________
Location:
Coastal South Carolina
rjniles is offline   Reply With Quote
Reply

Tags
armored cable, ground wire


Thread Tools Search this Thread
Search this Thread:

Advanced Search
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
33║ vs 35║ Nails Dilemma banzaitoyota Tools 1 12-28-2010 06:44 AM
My Dilemma: To Hire a contractor to do Everything, or Hire individual tradesmen; Headhunting55 Off Topic 4 08-26-2010 10:06 PM
Your thoughts on my staining dilemma? (Another sucker that fell for Behr) mklang Painting 3 08-05-2010 09:03 AM
Interesting flooring dilemma ply Flooring 1 09-23-2009 02:26 PM
help settling porch posts - a dilemma. wombosi Carpentry 9 10-10-2008 12:01 AM




Top of Page | View New Posts

Copyright © 2003-2014 Escalate Media. All Rights Reserved.