ECN Electrical Forum - Discussion Forums for Electricians, Inspectors and Related Professionals
ECN Shout Chat
ShoutChat
Recent Posts
Lowes Selling this fan
by timmp - 07/25/21 10:58 PM
How's all our Non-US folks doing?
by djk - 07/23/21 09:13 PM
Switched Receptacles -Top or Bottom?
by donles - 07/23/21 10:51 AM
Do You Travel?
by Bill Addiss - 07/20/21 04:26 PM
Backup Generator Done Right
by timmp - 07/18/21 12:20 PM
New in the Gallery:
February, North East Indiana
February, North East Indiana
by timmp, July 25
Red Green would be proud
Red Green would be proud
by timmp, July 25
Who's Online Now
0 members (), 32 guests, and 17 robots.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate Thread
Joined: Aug 2001
Posts: 459
J
Jim M Offline OP
Member
This was posted on a DIY site.

I have not read the quoted sections to see the differences.

Was this an oversight by the CMP's?

I know that this "all conductors run together" statement has been made many times, often even by me. But I am now going to begin the long tedious process of correcting this myth. It used to be true, but since the 1999 code, it no longer is. All conductors only need be run together if run in metal conduit or into metal boxes. If you are using NM-B cable and plastic boxes, and if your area is using the 1999 or 2002 NEC, then all conductors do not need to be run together.

For anyone wishing to research this further, please check out the differences in Article 300.3(B) between the 1996 and 1999 codes.

2017 / 2014 NEC & Related Books and Study Guides
Joined: Jan 2003
Posts: 4,391
I
Moderator
2002 NEC 300.3(B)
Quote
300.3(B) Conductors of the Same Circuit. All conductors of the same circuit and, where used, the grounded conductor and all equipment grounding conductors and bonding conductors shall be contained within the same raceway, auxiliary gutter, cable tray, cablebus assembly, trench, cable, or cord, unless otherwise permitted in accordance with 300.3(B)(1) through (4).

300.3(B)(3) Nonferrous Wiring Methods. Conductors in wiring methods with a nonmetallic or other nonmagnetic sheath, where run in different raceways, auxiliary gutters, cable trays, trenches, cables, or cords, shall comply with the provisions of 300.20(B). Conductors in single-conductor Type MI cable with a nonmagnetic sheath shall comply with the provisions of 332.31. Conductors of single-conductor–type MC cable with a nonmagnetic sheath shall comply with the provisions of 330.31, 330.116, and 300.20(B).

So they are correct if you follow the rules of 300.3(B)(3) and 300.20(B) you may run the conductors of a circuit separately.

You could run the 'hot' from the panel to a switch and the neutral from the panel to a light.

Why you would want to do this I have no idea unless you are running K & T.


Bob Badger
Construction & Maintenance Electrician
Massachusetts
Joined: Sep 2003
Posts: 650
W
Member
The only 'good' reason that one might want to do this is in a situation where you need more than 2 phase conductors and are limited to common ga-2 or ga-3 NM cable assemblies.

Not introducing large current loops is IMHO a good thing, but I don't see a significant problem with two NM cables running side by side, with the neutral in one cable and the corresponding phase conductors in the other.

-Jon

Joined: Jul 2004
Posts: 625
S
Member
I think I may have seen the discussion to which Jim is referring, or, at least, a similar one. Situation was for a combination bathroom fixture, with, as I remember, a light, a fan, and a heater. Power first went to the three-gang switch. The GC had screwed up before closing up the walls, and was trying to get the homeowner to go for running 2 12/2's, one with the hot and one of the switched legs, the other with other two switched legs.

I pretty much said, "No way in hell!" About ten posts later, someone came up with abovementioned references. I don't remember how it finally came out. It looks to me like it probably meets the letter of the Code, but I still think it's wrong, wrong, wrong!


Link Copied to Clipboard
Featured:

Tools for Electricians
Tools for Electricians
 

* * * * * * *

2020 Master Electrician Exam Preparation Combos
2020 NEC Electrician
Exam Prep Combos:
Master / Journeyman

 

Member Spotlight
richard
richard
L.I. New York
Posts: 99
Joined: August 2003
Top Posters(30 Days)
timmp 7
Rachel 4
djk 2
Popular Topics(Views)
281,463 Are you busy
215,101 Re: Forum
201,960 Need opinion
Powered by UBB.threads™ PHP Forum Software 7.7.5