ECN Electrical Forum - Discussion Forums for Electricians, Inspectors and Related Professionals
ECN Shout Chat
Top Posters(30 Days)
Potseal 11
Recent Posts
1913 American Electrician's Handbook
by annemarie1. 07/27/17 03:10 PM
600 KW 120/208 3 Phase Y protection
by Yooperup. 07/24/17 12:20 PM
Green House wiring
by ghost307. 07/20/17 09:10 AM
Permit Snafus...AHJs and Contractors Jump in
by HotLine1. 07/18/17 08:06 PM
New in the Gallery:
Housebilding DIY wiring
Popular Topics(Views)
239,365 Are you busy
174,822 Re: Forum
167,212 Need opinion
Who's Online Now
0 registered members (), 71 guests, and 3 spiders.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate This Thread
Page 1 of 2 1 2
#78324 - 09/09/01 11:37 PM equipment grounding conductors  
Barry  Offline
Junior Member
Joined: Jul 2001
Posts: 5
According to 250-118 emt is an acceptable grounding conductor.250-134(a) again tells me that an emt raceway is sufficient for grounding a fixed piece of equipment as long as the race raceway can safely handle the possible fault current,250-2(d).So with this all said my question is this.In what situation is a wire conductor REQUIRED for an equipment ground. From what I've read in the '99 code I would think my pipe run would satisfy the equipment grounding requirements for anything from a subpanel to a motor. This isn't the normal procedure of course but what is wrong with my thinking?
Thanks for any answers. Barry

2017 / 2014 NEC & Related Books and Study Guides

#78325 - 09/10/01 07:09 AM Re: equipment grounding conductors  
Redsy  Offline
Joined: Mar 2001
Posts: 2,056
Bucks County PA
This subject is controversial, as most of us agree that pulling a ground is always a good idea, though not required. However, bid work on larger jobs might result in the decision not to pull a ground due to cost, or the need to upsize conduits to accomodate the additional conductor.
Any instance where either an isolated ground, as in some data applications, or an insulated ground, as in health-care or swimming pool type installations would require an additional ground. See a previous post for a thread on this topic.

#78326 - 09/10/01 07:45 AM Re: equipment grounding conductors  
Glenn  Offline
Joined: Jan 2001
Posts: 75

Just my opinion.

A properly installed Metal Raceway system ( of the those permitted in 250-118 ) is adequate for an EGC.

But, I'm sure that most electricians and inspectors have seen systems where the couplings or other fittings have become pulled apart ( especially EMT systems ) or the locknuts are not properly tightened on rigid conduit systems.

I assume the design engineer(s) or the owner(s) has also seen the poorly installed metal raceway systems and do want to assure an adequate EGC system so do specify an EGC ( wire conductor ) be installed in certain metal raceway systems.

I remember seeing Code Q&A of such practices about 15 years ago in some of the "trade" magazines in which the ANSWERER did not emphasize the importance of the size of such additional EGC.

It should be sized per NEC 1999 250-122.

On two installations by the same designer, He had in the notes that all feeders in EMT over 1/0 have a number 6 AWG EGC in the raceway. In a few cases, if a properly sized EGC was to be installed the EMT size on the print(s) was not large enough. I called him and asked why he had requested a Number 6 EGC to be installed in these raceways. His answer was " In case a coupling pulls apart ". My questions to him was " What good is a Number 6 EGC in with 500 Kcmil circuit conductors if an EMT coupling pulls apart?".

My opinion again. If an (additional) EGC is specified on the prints or Spec's then it must be "full" size per 250-122.


#78327 - 09/10/01 04:35 PM Re: equipment grounding conductors  
Bill Addiss  Offline
Joined: Oct 2000
Posts: 3,878

You make a good point, it sounds reasonable to me.


#78328 - 09/10/01 11:09 PM Re: equipment grounding conductors  
Barry  Offline
Junior Member
Joined: Jul 2001
Posts: 5
Thank you for your answers. I'm asking these questions primarily to prepare for the upcoming Calif. test. Often what I'm taught to do in the field isn't necessarily required by code but is done for more practical reasons.

#78329 - 09/12/01 09:13 AM Re: equipment grounding conductors  
WARREN1  Offline
Joined: May 2001
Posts: 176
Greenville, SC, USA
We all must remember that the NEC requirements are the minimum for safety. Your test will be to see if you understand that minimum. What you do in the field should always be better than the minimum. I had an instructor say in a class one time that he didn't want to put a bunch of minimum rated electricians out there in the market place. Simply passing the test wasn't good enough. I'm sure you know to study hard and do the best you can on the test, and in your endeavor as an electrician. Wishing you the very best.

#78330 - 01/18/02 06:52 AM Re: equipment grounding conductors  

How useful would you rate the bare wire in AC for an EGC? It's a little flimsey. Is it even meant to be bonded?

#78331 - 01/18/02 07:21 AM Re: equipment grounding conductors  
George Corron  Offline
Joined: May 2001
Posts: 717
Lorton, Va USA
1999 NEC 333-19
It is not a bonding conductor, it is there to insure continuity of the outside skin. It is not landed, it is wrapped around the skin, or folded back.

#78332 - 01/18/02 07:48 AM Re: equipment grounding conductors  

Thats what I thought George, but I wasn't sure. I don't have a code book in front of me, but if I'm not mistaken, there is not even a requirement to fold it over or wrap it. It can be cut off flush with the end of the cable. Correct me if I'm wrong. I always wrap them anyway in such a way as they help hold the bushing on.

#78333 - 01/18/02 04:52 PM Re: equipment grounding conductors  
Elzappr  Offline
Joined: Dec 2001
Posts: 270
You are correct, TomBrooklyn.
Has anyone noticed lots of random breaks in the 'drain' wire. I'm just wondering if that is the norm, or perhaps I just had some factory defective cable. I wouldn't think breaks in the wire would hurt much, the fault current wouldn't necessarily loop around the spiral wrap of the armor just because there was a break in the wire..only if the break gaps were several inches apart..which wasn't the case with the cable I had been using.

Page 1 of 2 1 2

Member Spotlight
Berkley, MA
Posts: 144
Joined: March 2008
Show All Member Profiles 

2017 Master Electrician Exam Preparation Combos
2017 NEC Electrician
Exam Prep Combos:
Master / Journeyman


Shout Box
Powered by UBB.threads™ PHP Forum Software 7.6.0
Page Time: 0.024s Queries: 15 (0.004s) Memory: 0.8154 MB (Peak: 0.9879 MB) Zlib enabled. Server Time: 2017-07-27 20:47:42 UTC