parallel conductors and grounding conductor

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480sparky

480sparky

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Iowegia
Pierre C Belarge said:
Ken
read the first sentence of my post before yours.
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This part?

Pierre C Belarge said:
I believe what is being asked, is can the EGC itself be paralleled..........
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The first sentence of 250.122(F) requires them to be paralleled.

Pierre C Belarge said:
Also, the 2-1 AWG have the same current carrying capacity as 1 250 kcmil.
What is the issue you have with this?
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The second paragraph requires them to be sized to the OCD in T250.122. So if I have a 2000a breaker/fuse, I need a 250 EGC in each raceway.

M. D. said:
but you could run two 250s in each
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You could, but I'd fire you for doing that.
 
ohmhead

ohmhead

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ORLANDO FLA
Well thanks to everyone who had a input on this the way i see it and the way we have been doing it is Kens way for years .

One full sized grounding conductor in each parallel raceway.

Since ive been in the trade ive never seen it done any other way.

I have to get the 2008 code book to see if it says grounding conductor in 310.4 .

But iam thinking its also a unsafe practice meaning if you parallel in one conduit a EGC what would happen in the event of a fault that did not hit or connect both EGC but just one a burn out of one could cause a major fault and also effect the trip of the ocp ? comments is this safe ?
 
don_resqcapt19

don_resqcapt19

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Location
Illinois
Occupation
retired electrician
chris kennedy said:
The 08 is new and improved. 08 change in red.
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Chris,
What about 310.4(A)?
A) General. Aluminum, copper-clad aluminum, or copper conductors of size 1/0 AWG and larger, comprising each phase, polarity, neutral, or grounded circuit conductor shall be permitted to be connected in parallel (electrically joined at both ends).
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Per the CMP the words "shall be permitted" act to prohibit any other conductors in parallel. Something that I do not agree with, but that is the position of the CMP. It is my opinion that the current code wording does not prohibit paralleling conductors of any size or type as there is no way that you can read the words "shall be permitted" as prohibiting everything else.
 
don_resqcapt19

don_resqcapt19

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Location
Illinois
Occupation
retired electrician
LarryFine said:
Interesting that grounding conductor isn't listed.
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Larry,
That is my point and based on the CMP statement to my proposal, the paralleling of EGCs is not permitted.
6-8 Log #2235 NEC-P06
Final Action: Reject​

(310.4)​

____________________________________________________________

Submitter: ​






Donald A. Ganiere, Ottawa, IL​

Recommendation: ​


Revise as follows:​

310.4 Conductors in Parallel. Aluminum, coper-clad aluminum, or copper​

conductors of size 1/0 AWG and larger size #1 AWG and smaller , comprising

each phase, polarity, neutral, or grounded circuit conductor, shall be permitted
to not be connected in parallel (electrically joined at both ends).
Substantiation: ​




There is no code rule that prevents the installation of​

conductors smaller than 1/0 AWG in parallel in the current code. The existing​

rule just specifically permits the use of conductors 1/0 and larger in parallel,

but does not prohibit smaller conductors from being paralleled.
Panel Meeting Action: Reject
Panel Statement: The present language meets the requirements of Section
3.1.3 of the NEC Style Manual. Article 310.4 permits conductors 1/0 or larger
to be installed in parallel. The general rule is that conductors sized smaller than
1/0 are not permitted to be run in parallel.
Number Eligible to Vote: 11
Ballot Results: Affirmative: 11​






____________________________________________________________
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6-5 Log #2258 NEC-P06 ​





Final Action: Reject​


(310.4)

____________________________________________________________

Submitter: Donald A. Ganiere, Ottawa, IL
Comment on Proposal No: 6-8​


​





Recommendation: ​






This proposal should be accepted.​


Substantiation: ​






The panel rejected this proposal with the comment that the​


current wording complies with section 3.1.3 of the NEC Style Manual. Based

on the online version of this document, I think the panel meant to say section

3.1.2. This section says that the use of the words ?shall be permitted? are to be
used to ?indicate allowed optional or alternate methods.?
That would indicate that there must be some rule that says that conductors
cannot be installed in parallel. I am not aware of any such rule. Using the
current wording of ?shall be permitted? in no way limits the use of smaller
conductors installed in parallel. The rule should be changed to the wording in
the proposal to provide a valid restriction on the use of conductors smaller than
1/0 in parallel.
Panel Meeting Action: Reject
Panel Statement: The submitter is correct that the NEC Style Manual
reference in the panel statement on Proposal 6-8 should have been 3.1.2,
Permissive Rules. The parenthetical sentence immediately following the
referenced text states, ?(Note that these are still mandatory language and
constitute rules.)? Also, Item 4 under 3.3.1, Writing Style General Guidelines,
in the NEC Style Manual states, ?Use positive language, rather than negative,
wherever possible.? Section 250.118 defines the types of equipment grounding
conductors and uses the singular of ?conductor? except in 250.118(10). Section
310.4 deals with conductors that are run in parallel. The language specifically
allows conductors 1/0 or larger to be run in parallel, which means conductors
smaller than 1/0 in general are not permitted to be run in parallel.
Number Eligible to Vote: 11
Ballot Results: Affirmative: 11​


​






____________________________________________________________​
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I do not agree that the act of specifically permitting something also automatically prohibits something else.
 
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