Sleved romex with rigid pvc

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big john said:
I've already posted the article that plainly allows unsecued cables when they are fished. And fishing is how cables get pull through sleeves.

You changed your argument from first implying that the interior of a fished space was not concealed, to then saying if the ends of the sleeves were accessible the sleeve was not concealed so could not be fished through.

It seems pretty plain to me that if you can't get inside a sleeve to install straps, that is by definition "concealed" and allowed to be fished.

This is further supported by the very definition you posted that says wires in a raceway are considered concealed. Why would a sleeve be any different?
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big john said:
And, becaus I can't edit, with the exception of citing a definition for "concealed" you have not cited code substantuation for most of what you've asserted here, which goes to my original point of show me the writing and I may change my mind.
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I can't show you in writing, in Code, something that you are not willing to see... :(
 
Smart $ said:
I can't show you in writing, in Code, something that you are not willing to see... :(
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When I referred to philosophical dancing, this is exactly the type of thing I meant.

How about just admitting that despite the fact every flexible wiring method has securing requirements they also still have allowances for fishing it unsecured, and there is plainly no specific restriction prohibiting fishing through sleeves, and you were mistaken about believing Romex is different?
 
big john said:
When I referred to philosophical dancing, this is exactly the type of thing I meant.

How about just admitting that despite the fact every flexible wiring method has securing requirements they also still have allowances for fishing it unsecured, and there is plainly no specific restriction prohibiting fishing through sleeves, and you were mistaken about believing Romex is different?
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Hmm... philosophical dancing in the midst of your Jedi mind tricks??? :lol:
 
Smart $ said:
If you do not have to remove building or structure finish to get to the end of the sleeve or chase, it is NOT CONCEALED.
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This is where you go too far. Just because the ends of the sleeve are accessible does not mean the rest of the sleeve is not concealed. How much of the sleeve do you think you can access from the end? Maybe a length of one or two diameters. The rest is "inaccessible", i.e. "concealed".

Consider two different installations in a single story house over a crawlspace:

No sleeve: a hole is drilled in the top plate and bottom plate of a wall stud space and a cable is fished through from the attic to the crawl space.
Sleeve: during construction the same holes are drilled and a length of ABS pipe is run through the wall stud space but left open at both ends. At a later time a cable is fished through this pipe.

How does the presence of the ABS pipe change the applicability of 334.30(B)(1)? Both the interior of the stud space and the interior of the ABS pipe are concealed spaces.

Smart $ said:
The fish rule applies only where you have to remove some of the building or structure finished surface in order to fish the cable.
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No, only that the building finish or structure render the space through which the cable runs "concealed", i.e. "inaccessible".

Cheers, Wayne
 
Concealed. Rendered inaccessible by the structure or finish
of the building.


Informational Note: Wires in concealed raceways are considered
concealed, even though they may become accessible
by withdrawing them.

Ummmm...

(A) Type NM. Type NM cable shall be permitted as follows:
(1) For both exposed and concealed work in normally dry
locations except as prohibited in 334.10(3)

I do not see the problem with the cable itself in the raceway as Section 334 does not prohibit the act, in fact it encourages it in 334.10(5). I consider it both secured and supported in terms of meeting Section 334.30 if using the raceway for protection purposes. The rub is where it has to terminate to the enclosures and junction boxes and so on. The aspect of using a "sleeve" for the protection of the Type NM-B Cable we have no issues with, and the length (short) of this protective sleeve that is not clearly trying to be a complete run as stated in 300.18(A).

Far be it for me to be "logical" but keep in mind that the NEC does have provisions for when Type NM-B can be installed in raceways without individual securing to each cable assembly which we have previously posted in extreme detail. With that guidance we are left with the general rule to secure each cable to the enclosure or box (for brevity).

But lets assume we have a method of making that securing happen at an enclosure or junction box (brevity again)...maybe a raceway to a junction box with the ability to secure the Type NM-B as it enters into the box from a raceway ( Hey Bridgeport- Product Idea or they may have one already) at this point the raceway may or may not be used as "protection" yet it is indeed being used as a complete run which then the "lines" get blurry.

"The literal language of the Section 334.30(A) would require : at intervals not exceeding 1.4 m (4 1⁄2 ft) and within 300 mm (12 in.) of every outlet box, junction box, cabinet, or fitting" The implied exception to the rule is when the Type NM-B is within a raceway for protective purposes. Generally you protect it where needed, the cable then emerges from the raceway and we proceed to follow the rules of 334.30 as intended.

Now from a cable manufacturer perspective, we see no issues with heat dissipation and other aspects of the installation as long as Chapter 9, Table 1 rules are followed as well as the applicable notes. At the end of the day they are the same conductors inside the cable that would be installed without the cable sheathing for the most part. (i say most part because UL 719 allows THHN or it's Equivalent) and, as long as all other protective conditions apply, such as (310.15(B)(2) and (B)(3)) the various conditions of use adjustments and corrections, and others where applicable our cable and conductors are considered protected.

I think the literal words of the NEC make this one prime for the personal opinions and friendly debate. Now as someone always says (as if I don't actually work for a living or was an electrician for 25 years)...in the "real world" I have no problem with a cable installed in a raceway being supported and considered secure, no different than I consider a CT rated Type NM-B installed (where applicable) in a Cable Tray system which is simply a supporting system and is not considered a raceway at all. It is the AHJ that has to bring the situational awareness to the table (Common Sense) and allow creative compliance or equivalent intent.

However, the main reason I am forced to not permit Type NM-B in "complete runs" of raceways is less about 334.30(A) and more about 314.17(A) and (B) and 312.5(C), acknowledging all exceptions to the rule of course.

BTW - Happy Thanksgiving Everyone!
 
334.30(B)(1) also recognizes that there will have to be access points to get the wire into the space and by implication that the existence of access points does not make the space itself accessible.
Is fished between access points through concealed
spaces in finished buildings or structures and supporting is impracticable.
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Based on MastertheNEC statement... Yet, art. 312.5(C) specifically allows nm cable to be run in a conduit into a panelboard without having to fasten it to the box.
 
Dennis Alwon said:
Based on MastertheNEC statement... Yet, art. 312.5(C) specifically allows nm cable to be run in a conduit into a panelboard without having to fasten it to the box.
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But with a really long list of conditions....

(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 conduit or tubing systems by Table 1 of Chapter 9 of this Code and all applicable notes thereto.​
Informational Note: See Table 1 in Chapter 9, including Note 9, for allowable cable fill in circular raceways. See 310.15(B)(3)(a) for required ampacity reductions for multiple cables installed in a common raceway.
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GoldDigger said:
Note that 10' is longer than 4.5', thereby demolishing by concrete example the earlier statement about a maximum sleeve length of 4.5'.
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In fairness, I don't think this is the same thing.If a piece of conduit attaches to an enclosure, in my opinion it's no longer a sleeve and falls under the rules for a raceway. E.g.: I can legally run a bunch of Romex through a plumbing pipe sleeve. If I connect that plumbing pipe to the top of my panel, I have created a violation.
 
MasterTheNEC said:
Concealed. Rendered inaccessible by the structure or finish
of the building.


Informational Note: Wires in concealed raceways are considered
concealed, even though they may become accessible
by withdrawing them.

...I have no problem with a cable installed in a raceway being supported and considered secure, no different than I consider a CT rated Type NM-B installed (where applicable) in a Cable Tray system which is simply a supporting system and is not considered a raceway at all. It is the AHJ that has to bring the situational awareness to the table (Common Sense) and allow creative compliance or equivalent intent.

...
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Dennis Alwon said:
Based on MastertheNEC statement... Yet, art. 312.5(C) specifically allows nm cable to be run in a conduit into a panelboard without having to fasten it to the box.
Click to expand...

GoldDigger said:
But with a really long list of conditions....
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GoldDigger said:
Note that 10' is longer than 4.5', thereby demolishing by concrete example the earlier statement about a maximum sleeve length of 4.5'.
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Please note I did not say a sleeve cannot be longer than 4.5', only that such a sleeve, according to existing Code text, must be listed conduit or tubing. It seems everyone keeps leaving this major distinction out of the discussion.

big john said:
In fairness, I don't think this is the same thing.If a piece of conduit attaches to an enclosure, in my opinion it's no longer a sleeve and falls under the rules for a raceway....
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That's absolutely correct. This is a special condition where Code considers the open-ended conduit a complete run. You also run into a similar condition quite often when transitioning in or out of cable tray.
 
wwhitney said:
This is where you go too far. Just because the ends of the sleeve are accessible does not mean the rest of the sleeve is not concealed. How much of the sleeve do you think you can access from the end? Maybe a length of one or two diameters. The rest is "inaccessible", i.e. "concealed".

Consider two different installations in a single story house over a crawlspace:

No sleeve: a hole is drilled in the top plate and bottom plate of a wall stud space and a cable is fished through from the attic to the crawl space.
Sleeve: during construction the same holes are drilled and a length of ABS pipe is run through the wall stud space but left open at both ends. At a later time a cable is fished through this pipe.

How does the presence of the ABS pipe change the applicability of 334.30(B)(1)? Both the interior of the stud space and the interior of the ABS pipe are concealed spaces.


No, only that the building finish or structure render the space through which the cable runs "concealed", i.e. "inaccessible".

Cheers, Wayne
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Forget about that rule for now...

Let's go back to the general statement....
334.30 Securing and Supporting. Nonmetallic-sheathed
cable shall be supported and secured by staples, cable ties,
straps, hangers, or similar fittings designed and installed so
as not to damage the cable, at intervals not exceeding 1.4 m
(41⁄2 ft) and within 300 mm (12 in.) of every outlet box,
junction box, cabinet, or fitting. Flat cables shall not be
stapled on edge.


Sections of cable protected from physical damage by raceway
shall not be required to be secured within the raceway.
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Now let's examine the fish rule thereunder...
(B) Unsupported Cables. Nonmetallic-sheathed cable shall
be permitted to be unsupported where the cable:
(1) Is fished between access points through concealed
spaces in finished buildings or structures and supporting
is impracticable.
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This rule only covers supporting of the cable. It does not cover the securing requirement of the general statement.
 
Smart $ said:
This rule only covers supporting of the cable. It does not cover the securing requirement of the general statement.
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By that logic, NM cable can never be fished more than 4.5 feet, unless you can secure it inside the concealed space, or you fish it through a raceway. Given that fishing NM cable through building cavities is an industry standard practice, I conclude that 334.30(B) is implicitly exempting fished cable from securing as well as supporting. If the exact wording doesn't support that, it is a technical error in the wording and should be corrected for the 2020 edition.

Cheers, Wayne
 
wwhitney said:
By that logic, NM cable can never be fished more than 4.5 feet, unless you can secure it inside the concealed space, or you fish it through a raceway. Given that fishing NM cable through building cavities is an industry standard practice, I conclude that 334.30(B) is implicitly exempting fished cable from securing as well as supporting. If the exact wording doesn't support that, it is a technical error in the wording and should be corrected for the 2020 edition.

Cheers, Wayne
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Feel free to submit a Public Input.
 
Smart $ said:
Please note I did not say a sleeve cannot be longer than 4.5', only that such a sleeve, according to existing Code text, must be listed conduit or tubing. It seems everyone keeps leaving this major distinction out of the discussion.
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Not everyone... I believe that was what I posted way back in post 52
 
Smart $ said:
...Now let's examine the fish rule thereunder...This rule only covers supporting of the cable. It does not cover the securing requirement of the general statement.
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Because it's literally impossible to secure a cable without simultaneously supporting it, so it goes without saying that if a cable is permitted to be unsupported it is always also going to be unsecured.
 
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