Listing for conductors

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roger

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Last sentence in 334.30 - "Sections of cable protected from physical damage by raceway shall not be required to be secured within the raceway"
And now we look at the definition of raceway.

Roger
 

iwire

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I think this is one of those rules where it was meant as an example. It would make no sense otherwise. I have never seen an inspector who would only allow that type of install in a basement

I think what Don is saying, and how I feel as well is that the requirement for the sheath to extend into the box only applies to a box on the wall of a unfinished basement and not every time NM is running a raceway.

Crazy but that is how the NEC evolved.
 

infinity

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some people will interpret the end of that "protective sleeve" to be the equivalent of a box cabinet or fitting and require securing it within 12 inches per 334.30. I do find error in that drawing by calling it a raceway when it should be called a "protective sleeve" or something similar. It may be made out of something that is listed as a raceway but it is not used in accordance to raceway articles in this case. 300.18(A) tells us that raceways "shall be installed complete between outlet, junction, or splicing points prior to the installation of conductors".

I agree, I fail to see how that is complete.
 

roger

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I agree, I fail to see how that is complete.
Ok, if it makes everybody feel better let's just apply 300.12 Exception No 1 for this scenario. Take note that it uses the term " short sections of raceways"

Roger
 

kwired

Electron manager
Location
NE Nebraska
Ok, if it makes everybody feel better let's just apply 300.12 Exception No 1 for this scenario. Take note that it uses the term " short sections of raceways"

Roger


That exception does allow for a short section of raceway to provide physical protection including a short section that does not have an enclosure attached to one end like what we have been primarily talking about. There is no mentioning of just what length is considered short either.
 

Dennis Alwon

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I think what Don is saying, and how I feel as well is that the requirement for the sheath to extend into the box only applies to a box on the wall of a unfinished basement and not every time NM is running a raceway.

Crazy but that is how the NEC evolved.

I understood that but I have no idea why it was written that way. I can only say it was an error in thought or something. Who knows ... We are also allowed to sleeve into panelboards under certain conditions. Maybe that want the sleeve to be accessible for some reason. I have done it often inside finished walls but perhaps there is some reason that it should not be done. If I remember I will write a proposal on that and see where it goes.
 

GoldDigger

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some people will interpret the end of that "protective sleeve" to be the equivalent of a box cabinet or fitting and require securing it within 12 inches per 334.30. I do find error in that drawing by calling it a raceway when it should be called a "protective sleeve" or something similar. It may be made out of something that is listed as a raceway but it is not used in accordance to raceway articles in this case. 300.18(A) tells us that raceways "shall be installed complete between outlet, junction, or splicing points prior to the installation of conductors".
In the illustration, it looks like the NM is stapled within 12" of the point where it enters the raceway, although there is no dimension callout for that distance.
And there is some kind of protective bushing where the NM enters the cut end of the conduit.
 

iwire

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Massachusetts
I agree, I fail to see how that is complete.

If you do an NEC search for 'sleeve' every time it is used it appears clear it is just an isolated section of raceway not connected to any enclosure.


On the other hand if we look at 312.4(C) it calls the conduits that are open on one end raceways.

(C) Cables. Where cable is used, each cable shall be secured to the cabinet, cutout box, or meter socket enclosure.

Exception: Cables with entirely nonmetallic sheaths shall be permitted to enter the top of a surface-mounted enclosure through one or more nonflexible raceways not less than 450 mm (18 in.) and not more than 3.0 m (10 ft) in length, provided all of the following conditions are met:

(a) Each cable is fastened within 300 mm (12 in.), measured along the sheath, of the outer end of the raceway.

(b) The raceway extends directly above the enclosure and does not penetrate a structural ceiling.

(c) A fitting is provided on each end of the raceway to protect the cable(s) from abrasion and the fittings remain accessible after installation.

(d) The raceway is sealed or plugged at the outer end using approved means so as to prevent access to the enclo-sure through the raceway.

(e) The cable sheath is continuous through the race-way and extends into the enclosure beyond the fitting not less than 6 mm (1?4 in.).

(f) The raceway is fastened at its outer end and at other points in accordance with the applicable article.

(g) Where installed as conduit or tubing, the allowable cable fill does not exceed that permitted for complete con-duit or tubing systems by Table 1 of Chapter 9 of this Code and all applicable notes thereto.

Notice it does not call these raceways sleeves.
 

Galt

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Wis.
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master electrician and refrigeration service tech.
In Wis. we have an exception in the state code allowing us to put NM in conduit one foot min. Ten foot max. Without being secured on either end.
 

don_resqcapt19

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Illinois
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I think what Don is saying, and how I feel as well is that the requirement for the sheath to extend into the box only applies to a box on the wall of a unfinished basement and not every time NM is running a raceway.

Crazy but that is how the NEC evolved.
No...I am saying, based on the code wording, the only time you can protect the NM with a conduit or tubing sleeve is when the sleeve is installed on a basement wall.
 

kwired

Electron manager
Location
NE Nebraska
Around here we sleeve with PVC and just use a pvc coupling at the top of the pipe.
If I am sleeving with PVC I have always just reamed the end of the end of the PVC and used no additional fittings.

No...I am saying, based on the code wording, the only time you can protect the NM with a conduit or tubing sleeve is when the sleeve is installed on a basement wall.

Why limited to basement walls. Install exactly same thing on same type of wall, but not in a basement, and it is wrong? More rare but not impossible would be a sleeve to something on a ceiling that is not able to be fished or concealed somehow.
 

don_resqcapt19

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Illinois
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Per the style manual the term "shall be permitted" acts as an exception. In my opinion 334.15(C) acts as an exception to 314.17(B) & (C) and to 334.30. When you install NM in a sleeve that connects to a box, you cannot comply with the rules in 314.17 or 334.30, so the exception is needed. The exception, 334.15(C), is very specific as to its application.
 

Dennis Alwon

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Per the style manual the term "shall be permitted" acts as an exception. In my opinion 334.15(C) acts as an exception to 314.17(B) & (C) and to 334.30. When you install NM in a sleeve that connects to a box, you cannot comply with the rules in 314.17 or 334.30, so the exception is needed. The exception, 334.15(C), is very specific as to its application.


I agree that 334.15(C) is very specific however there are other areas of the code that allow nm to be sleeved in a raceway. I really don't know but I have a feeling that section was not meant to be just for basements as that would make no sense at all
 

Smart $

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Ohio
I agree that 334.15(C) is very specific however there are other areas of the code that allow nm to be sleeved in a raceway. I really don't know but I have a feeling that section was not meant to be just for basements as that would make no sense at all
Just for clarification, it is not basements in general. It is even more specific: unfinished basements and crawl spaces.
 

kwired

Electron manager
Location
NE Nebraska
Just for clarification, it is not basements in general. It is even more specific: unfinished basements and crawl spaces.

Maybe I should read the section before posting. It does apply to unfinished basements and crawl spaces. I bet I have violated this many times, and inspectors have passed it many times also.
 

mwm1752

Senior Member
Location
Aspen, Colo
No...I am saying, based on the code wording, the only time you can protect the NM with a conduit or tubing sleeve is when the sleeve is installed on a basement wall.

Seems to me exposed work can be pretty much anywhere on the building and it is mandatory to protect the cable inserted in the raceway -- could be box to box -- we all know this excludes wet locations with NM

334.15 Exposed Work
In exposed work, except as provided in 300.11(A), cable shall be installed as specified in 334.15(A) through (C).
(B) Protection from Physical Damage. Cable shall be protected from physical damage where necessary by rigid metal conduit, intermediate metal conduit, electrical metallic tubing,

Here is the UL section which does rate the wire @ 90 C & ties it to table 310.16
NONMETALLIC-SHEATHED CABLE (PWVX)
USE This category covers Types NM-B and NMC-B nonmetallic-sheathed cable, rated 600 V, intended for use in accordance with Article 334 of ANSI/NFPA 70, ??National Electrical Code?? (NEC), and Listed in copper sizes 14 to 2 AWG inclusive and aluminum or copper-clad aluminum sizes 12 to 2 AWG inclusive.
This cable contains conductors rated 90?C; however, the ampacities of the cable are those of 60?C conductors as specified in Article 334 and Table 310.16 of the NEC
 
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