250.122A

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Greg1707

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Alexandria, VA
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Business owner Electrical contractor
In the second paragraph of this section it states: "EGC shall be permitted to be sectioned within a multi conductor cable, provided the combined circular mil area complies with Table 250.122.

What does this mean in plain english?
 

iwire

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Location
Massachusetts
In the second paragraph of this section it states: "EGC shall be permitted to be sectioned within a multi conductor cable, provided the combined circular mil area complies with Table 250.122.

What does this mean in plain english?

Some larger cables do not have a single EGC in them, some of them use two or three EGCs that are combined at each end to make the size comply with 250.122
 

iwire

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Massachusetts
Common example may be the bare concentric strands that are in a type SE cable or other similar designed cables.

I may be mistaken but I am pretty sure that concentric strands predate that code section by decades.

If I recall correctly that code section has to do with types of MC cables that have two or more distinct EGCs in them that are intended to be terminated together at both ends.
 

iwire

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Staff member
Location
Massachusetts
Something like this.



teck90.jpg
 

kwired

Electron manager
Location
NE Nebraska
I may be mistaken but I am pretty sure that concentric strands predate that code section by decades.

If I recall correctly that code section has to do with types of MC cables that have two or more distinct EGCs in them that are intended to be terminated together at both ends.

Could be. What is reasoning to make cable that way? Can't say I have ever run into such a thing.

Ultimately you are still using all the strands to make up the entire EGC just like you would with a concentric type conductor.

If this section only applies to that type of cable they are just reinforcing what should otherwise be part of the listing instructions.
 

iwire

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Staff member
Location
Massachusetts
Could be. What is reasoning to make cable that way? Can't say I have ever run into such a thing.

Ultimately you are still using all the strands to make up the entire EGC just like you would with a concentric type conductor.

If this section only applies to that type of cable they are just reinforcing what should otherwise be part of the listing instructions.

Some of your questions answered here:

From the 2011 ROP

5-285 Log #1645 NEC-P05 Final Action: Accept
(250.122(A))
_______________________________________________________________
Submitter:
James M. Daly, Upper Saddle River, NJ

Recommendation: Add a second paragraph:
“Equipment grounding conductors shall be permitted to be sectioned within a
multiconductor cable, provided the combined circular mil area complies with
Table 250.122.”

Substantiation: Addition of this additional paragraph will correlate with 310.13 and the multiconductor cable product standards and is more
appropriately located in 250.122. A single equipment grounding conductor
frequently will not fit in the interstice between the insulated conductors in a multiconductor cable and is required to be sectioned for manufacturing
purposes. The product standards already permit sectioned conductors. The use of a positive code rule rather than an exception is in accordance with 3.1.4 of the NEC Style Manual.

Panel Meeting Action: Accept

Number Eligible to Vote: 16

Ballot Results: Affirmative: 16
___________________________


As far as SE with concentric conductors the difference I see is those are made to be twisted together and form one single conductor that would be landed on one terminal.

The MC has two or more EGCs made of twisted strands, each one of these EGCs is a separate conductor and must be landed on sperate terminals or an appropriately listed terminal etc and under those conditions I could see an inspector questioning it without the NEC spelling it out.
 
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