Wireway U pulls

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M, its always for the good of all to keep up on the requirements, i don't remember alot either and have to go back and refresh also.
Attached is an example of what i think 314.28(A)2 is saying. Existing conduits in left hand side of box meet the opposite wall requirement of 12". The conduits on the right were added and a barrier was installed to keep the box without changing it.
Rick

View attachment 3160
 
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Gus and Rick,

Thanks again for your help,

Since I am a morning person and early AM is when I am at my best understanding level, and since it has been rumored that I may utilize certain pharmaceutical enhancements to assist with my difficult times of Code understanding :) (which I would be unable to share with you :) at any time) ?

I will again in the AM attempt to re-understand what I thought I previously understood, but maybe never did? I am in the meantime posting my e-mail discourse (Wait ... I hope I said what I meant to say... :) with NFPA staff for your review:

(? staff names omitted to protect the helpful :) ?)



Topic: NFPA 70-05 Section 366.58(B) Auxiliary Gutters Used as Pullboxes, Section 376.23(B) and Section 378.23(B) ? Wireways used as Pullboxes

Statement:
Within Section 366.58(B) Auxiliary Gutters Used as Pullboxes, the Document NFPA 70-05 informs that (paraphrasing) where insulated conductors of #4 AWG and larger are pulled through an auxiliary gutter, the distance between raceway entries enclosing the same conductor is not permitted to be less than that required for straight pulls, found in Section 314.28(A)(1), and angle pulls, found in Section 314.28(A)(2). This requirement is duplicated for metallic wireway (Article 376) and nonmetallic wireway (Article 386).

My initial understanding from reading this auxiliary gutter requirement was this auxiliary gutter requirement was limited to the distance between conduit entries only. For example, limited to the diagonal requirement for angle pulls only, which is the distance between conduit entries enclosing the same conductor. My review of the request for proposals on the 2005 NEC and other interpretations I have received from other interested persons have led me to believe this requirement for auxiliary gutters used as pullboxes may include all the requirements of 314.28(A)(1) and (A)(2), which would include the required dimension to the opposite wall for angle pulls.

Question:
Do the requirements of Sections 366.58(B), 376.23(B) and 378.23(B) require compliance with all the requirements from 314.28(A)(1) and (A)(2), or only the distance between conduit entries enclosing the same conductor (which would be the diagonal requirement for angle pulls)?

NFPA Staff Response:
In the three NEC sections that you have cited (366.58(B), 376.23(B), and 378.23(B) the reference to 314.28(A)(1) and (A)(2) is for the purposes of determining the minimum distance between raceways enclosing the same conductor that enter auxiliary gutters, metal wireways and nonmetallic wireways.



Statement:
Section 366.58(B) uses the phrase ?Where insulated conductors 4 AWG or larger are pulled through an auxiliary gutter?.

Question:
Can a situation exist where conductors of #4 or larger enter an auxiliary gutter via a raceway (from equipment the gutter supplements) and Section 366.58(B) would not apply?

Question:
Can a situation exist where conductors of #4 or larger exit an auxiliary gutter via a raceway (on route to remote equipment served via the auxiliary gutter) and Section 366.58(B) would not apply?

NFPA Staff Response:
2. & 3. Yes. If the conductors enter or exit the auxiliary gutter via a raceway and are run through the gutter to connect to the terminals of equipment for which the auxiliary gutter is supplementing the wiring space, i.e. a panelboard or switchboard the requirements of 314.28(A)(1) and (A)(2) are not applicable to the installation. The requirements of 312.6(A) apply to the amount of wiring bending space at the terminals to which the conductors are connected.



This may help, or it could... make it worse :) ...

mweaver
 
NFPA Staff Response:
2. & 3. Yes. If the conductors enter or exit the auxiliary gutter via a raceway and are run through the gutter to connect to the terminals of equipment for which the auxiliary gutter is supplementing the wiring space, i.e. a panelboard or switchboard the requirements of 314.28(A)(1) and (A)(2) are not applicable to the installation. The requirements of 312.6(A) apply to the amount of wiring bending space at the terminals to which the conductors are connected.



This may help, or it could... make it worse :) ...

mweaver

The NFPA70 staff response answer to question 2 and 3 are for when a raceway comes in the top or bottom and travels horizontal to a piece of equipment. The bending radius of table 312.6A apply.The 314.28(A)2 would not. This is a different situation from the U-turn calculations.

and not so good, the statement he makes is to follow the A2 requirement.
staff said:
I have received from other interested persons have led me to believe this requirement for auxiliary gutters used as pullboxes may include all the requirements of 314.28(A)(1) and (A)(2), which would include the required dimension to the opposite wall for angle pulls.
 
M, its always for the good of all to keep up on the requirements, i don't remember alot either and have to go back and refresh also.
Attached is an example of what i think 314.28(A)2 is saying. Existing conduits in left hand side of box meet the opposite wall requirement of 12". The conduits on the right were added and a barrier was installed to keep the box without changing it.
Rick

View attachment 3160



Rick
What about the requirement to keep the 2 inch raceways 12 inches apart?
 
Gus and Rick,

Thanks for your continued efforts to clarify this for me.

This is obviously falling on my deaf ears and thick head this afternoon and I am plagued with my (apparently failing) memory of that conversation with NFPA staff on this very subject, which I really thought I understood, at the time...


For now I should defer to your experience and I will review those posts I had with NFPA staff (I should still have them...), which may help me again...

... This won't be the first time I was led by the hand, and still got it wrong :) ...won't be the last either, I am sure...

Regardless, thanks for your help, I do appreciate it,

mweaver
You have the code rule correct. It is my opinion that the code rule is wrong. The reason for the "opposite wall" rule is to avoid conductor insulation damage and that problem exists for both wireways and pull boxes. For some reason the code only addresses the space between the conduits for the wireway and both the space between the conduits and to the opposite wall for pull boxes.
 
I'm not sure if I'll ever be totally comfortable with these situations, but, IMHO, the part of the confusion here is wireway vs auxiliary gutter.
In the NFPA response to mweaver they specifically refer to Art 366.
Part of the definition of an auxilary gutter states:"The enclosure is designed for conductors to be laid or set in place after the enclosures have been installed as a complete system."
To me this differs form the pull box or wireway in that conductors are "laid in" and not "pulled in". My opinion is that if you are "pulling" into the enclosure (wireway, box, auxiliary gutter or whatever" then Art 314 rules apply.
If you are "laying in" conductors, say between two adjacent panelboards, then only Art 312 applies. To me 366.58 clarifies that.
But that if, of course, an opinion and I could be wrong.
 
Don 376.23B refers you to 314.28A2 for wireways.
Rick
Rick,
Yes it does, but only for the purpose of the conduit spacing, not for the opposite wall issue.
(B) Metallic Wireways Used as Pull Boxes. Where insulated conductors 4 AWG or larger are pulled through a wireway, the distance between raceway and cable entries enclosing the same conductor shall not be less than that required by 314.28(A)(1) for straight pulls and 314.28(A)(2) for angle pulls. When transposing cable size into raceway size, the minimum metric designator (trade size) raceway required for the number and size of conductors in the cable shall be used.
The words in bold limit what part of 314.28(A) you apply for wireways. You only apply the conduit spacing part. If the code would leave those words out, then all of 314.28(A) would apply, but with those words in the code rule for wireways, there opposite wall rule does not apply.
 
The words in bold limit what part of 314.28(A) you apply for wireways. You only apply the conduit spacing part. If the code would leave those words out, then all of 314.28(A) would apply, but with those words in the code rule for wireways, there opposite wall rule does not apply.

AHHH, i think the light bulb just came on!!. I thought the reference was to follow all of the 314.28 rule for wireways.
icon3.gif
 
For the benefit of everyone following this thread:

I do want to point out that the NFPA staff response is dated 03-26-07. It was addressed to staff in reference to the 2005 version of the NEC.

All Code Sections which are relevant to auxiliary gutters and wireways WHEN used as pullboxes are unchanged in the 08 NEC


...Whatever NFPA Staff responded with, in regards to the 05 NEC, should still be applicable in the exact same way for the 08 NEC? (at least as I see it...)



Important ... ...for clarity ...

at the bottom of Post #23, Rick has quoted a statement noting it as originally posted by NFPA Staff.

This is in error? this statement (also directly below) was made by mweaver directed to NFPA staff? (...although for me, that doesn't really change anything...)

statement by mweaver NOT from NFPA Staff...
...I have received from other interested persons... have led me to believe this requirement for auxiliary gutters used as pullboxes may include all the requirements of 314.28(A)(1) and (A)(2), which would include the required dimension to the opposite wall for angle pulls...


There are only two staff responses to three posed questions in my post #22?

All other text represents mweaver?s statements to staff?




To be clear, I posed this question to NFPA staff after a followup of lengthy conversations with others (who can remain nameless :) ) on this very issue which did encompass Mr. Holt?s graphic (It was a graphic in post #1 or one quite similar) depicting the application of wireways used as pullboxes. When I read new language in the 05 NEC on this issue and then looked at Mr. Holt's graphic, I just could not see where he was comming up with the opposite wall requirement, affecting the wireway vertical width for his U pull. For me, the NEC text (inside the Articles for gutters and wireways) did not include this language, and it should not be assumed that it was inclusive... For me, the pullbox language (inside the Articles for gutters and wireways) is very clearly instructing what part of Section 314.28(A)(2) should be considered (it is clearly not requiring consideration of all parts...). ...at least for me ...

My initial purpose for posing said questions to NFPA was to determine when auxiliary gutters and wireways were considered as being utilized to be pullboxes, and EXACTLY what is required when they are used as such. And also when the pullbox requirements will have NO impact on gutters and wireways?

For me, the NFPA Staff responses have acomplished this... at the time I recieved the response and now upon much later review... The NFPA Staff's second response (for me...) distinguishes (although not as clearly as I would like...) when these pullbox requirements will not apply and other requirements [the requirements of 312.6(A)] will apply... For me, there is a clear demarcation here... For me, this makes both of Mr. Holt's graphics from post #1 incorrect and not in conformance with the NFPA staff responses... and not representative of the NEC gutter and wireway pullbox requirements.

... It is definitely possible that I may have to agree to disagree with many of you on this pullbox issue, until additional clarity and language is available ...

In discussing this with several members of the enforcement branch (back in early 07 when this came to a head for me?), to determine when gutter and wireway IS supplementing the wiring space, i.e. a panelboard or switchboard, and the requirements of 314.28(A)(1) and (A)(2) are not applicable to the installation; one jurisdiction (also to remain nameless, cause I cannot remember who) provided more clarity for their local level, and established a raceway length of a certain footage (such as 6 feet). If the raceway entering or exiting the gutter or wireway is longer than 6 feet (for example) the raceway entering the gutter or wireway cannot be supplementing another enclosure. If the raceway entry is not supplementing, then it must be using (a portion of) the gutter or wireway as a pullbox and Sections 366.58(B), 376.23(B), and 378.23(B) (the pullbox requirements) will apply ONLY to the appropriate gutter or wireway portion of the installation.

In my opinion today (and at that time in 07 others agreed? not that it matters today...) wireways can supplement the wiring space (of other enclosures) just as gutters can? and while gutters and wireways are supplementing wiring space of other enclosures; portions of the same gutters and wireways can also be used as pullboxes. Only the appropriate requirements will apply to the appropriate portions of the gutter or wireway installations?


What makes all this problematic for all of us is that without clear and universal understanding of the pullbox requirements contained within the auxiliary gutter and wireway NEC Articles, enforcement is going to vary widely based upon each jurisdiction?s understanding of the requirements? One easy solution I promote is that you could all just agree with me and NFPA staff :) ? (although admittedly, more clarification from the CMP is probably going to be necessary here?)




REALLY, REALLY Important... ?for me :) ? anyway
One extremely noteworthy (and certainly the most important :) ) contribution to this thread that has caught my attention this AM, is the obvious wisdom and insight of another longtime experienced poster - moderator (who is obviously of extreme superior intelligence, and also must be an excellent judge of character :) ? A man who has the precision to cut through the muck (with the accuracy of a surgeon's scalpel) and see the Code clearly and apply it appropriately... :) ...) Don, Illinois, who has recognized (right off) that I actually had this right all along :).
(assuming I have understood him correctly :) ...)


To the OP: Twoskinsoneman... Hey, Thanks for posting this ? It leads to universal understanding of these requirements...

Mweaver (who is guessing this saga will continue on....)
 
Mweaver, i agree with your assement and Don's assement of the way 376.23 is writen now ( because of the lack of wording ), that the opposite wall requirement does not apply to wireways.

It does boggle my mind that you can pull 4/0 conductors in a 2-1/2" conduit through a 4" x 4" wireway and meet code.

Thanks for holding fast and keeping to your guns.

Rick
 
Rick, you are welcome.

I must actually extend my thanks to the entire forum membership who provides this discourse which enhances my personal understanding of some of these very difficult and perplexing issues.

I do agree wholeheartedly with your statement: ?It does boggle my mind that you can pull 4/0 conductors in a 2-1/2" conduit through a 4" x 4" wireway and meet code.?


?But a cautionary note to all:
This may be compliant in Peculiar MO ? But it may NOT be compliant in Poughkeepsie NY? :) ?
(We, as an industry, gotta get this language pinned down so whatever it is, it will be compliant in EVERY jurisdiction? because we all understand it the very same way...)

mweaver
 
Clarification for 2011 probably won't happen

Clarification for 2011 probably won't happen

Please pardon my response to my own post which bumps this to the top again, but I did want to add here....


Just in case anyone was wondering if the 2011 Code cycle will offer any relief, clarity or understanding to the pullbox requirements for auxiliary gutter and wireways?

I have already checked and there appear to be ZERO proposals to Sections 366.58(B), 376.23(B) and 378.23(B). (...meaning the text should be identical for the 2011 cycle...)


My understanding is that:

This means that for those who are interested in developing language to clarify these issues will be able to polish said language for their 2014 proposals :) ?


mweaver
 
well..now that the issue is settled :) ...let me add a note I just received from my mentor, a CMP member(ret)}:
The current requirements come from a revision to the 2002 NEC on proposals by Wayne Lilly and Phil Cox, Proposals 8-410 and 8-411 in the 2001 ROP. At that time these requirements were in 362-6 of the 1999 NEC but was moved to new Article 376 in the 2002 NEC as metal and nonmetallic raceways were separated into their own NEC Articles and this was reflected in the 2002 NEC as 362-6 became 376.23 (A) and (B) with the issue at hand being in (B). Also "-" became "." in the 2002 NEC in section numbers and small subsection letters such as (a) became (A). At that time, Wayne Lilly's proposal was accepted and Phil Cox's proposal was Accepted in Principle with both stating the same objectives.

Wayne Lilly's substantiation that is part of the panel acceptance stated "The addition of (a) to 376-6 is a specific reference. A reference to the entire 373-6 is confusing because we don't know whether to use 373-6(a) or 376-6(b). Also, where possible, we are to provide a specific reference. Metallic wireways, by definition, are for use with conductors which 'are laid in place after the wireway has been installed as a complete system.' The requirements for deflection of conductors in 362-6 are intended to be utilized with conductors which are 'laid in place.' In today's installations wireways are also being used as pull boxes. Where wireways are being used as pull boxes the dimensional requirements for pull boxes should apply." The substantiation is as much a part of the proposal as the proposal and CMP-8 accepted both the proposal and substantiation.

I have also attached Proposals 8-410 and 8-411 from the ROP report so you can read them for yourself.

Therefore, it is my opinion that the reference currently in 376.23(B) of that Section references the entire requirements of current 314.28(A)(1) and (A)(2).

*********************************************************

The ROP's he attached were too big to upload here. If any one desires a copy, message me and I will forward.
 
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...
Therefore, it is my opinion that the reference currently in 376.23(B) of that Section references the entire requirements of current 314.28(A)(1) and (A)(2).

*********************************************************

The ROP's he attached were too big to upload here. If any one desires a copy, message me and I will forward.
Gus,
I haven't gone back and looked at the ROPs and that may have been the intent, but if it was, once again the intent does not match the code wording. The wording clearly limits the application of 314.(A) to the spacing between the raceways and does not apply the "opposite wall" rule.
(B) Metallic Wireways Used as Pull Boxes. Where insulated conductors 4 AWG or larger are pulled through a wireway, the distance between raceway and cable entries enclosing the same conductor shall not be less than that required by 314.28(A)(1) for straight pulls and 314.28(A)(2) for angle pulls. When transposing cable size into raceway size, the minimum metric designator (trade size) raceway required for the number and size of conductors in the cable shall be used.

Maybe you could ask John to look in on this thread or forward this post for his comment.
 
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Which language should actually prevail ??

Which language should actually prevail ??

Gus,
While I would (in spirit) agree with the statement of your opinion in post # 36 (due to the original submitter's "apparent intent"...), (in my opinion :) ) your expressed opinion does not appear to reflect the NFPA staff interpretation (who had access to the same substantiation materials...) I have provided in post #32.


In addition, as Don stated in post #37:

...The wording clearly limits the application of 314.28(A) to the spacing between the raceways and does not apply the "opposite wall" rule...



The pullbox requirements for auxiliary gutter and wireway may need future modification to meet the requirements of the original submitter's intent.
However, the language which currently exists is enforceable and the opposite wall requirement clearly does not apply.



Not to open another can of worms, but ...
When Code language is found to be in opposition to the intent of the original submitter, I (personally) believe the actual Code language, which is adopted by jurisdictions as a legal, enforceable, and regulatory instrument should prevail... ...Which language should actually prevail?

mweaver
 
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