Sleved romex with rigid pvc

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Jack Hass

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Location
NY
Is it permissible to run (2) 6/3nmb in a 2" pvc conduit for a distance of 8'? This would be in an interior wall.
 
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Jack Hass

Member
Location
NY
The sleeved romex would be in an interior wall between floors. The wire run is about 80'. Only sleeved for protection 8' between the 1st and 2nd floor
 
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Jack Hass

Member
Location
NY
I was trying to figure out the conduit fill for the (2) 6/3nmb's. On another thread 6/3nmb is listed as .3318 diameter. How exactly do I do the calculation for the conduit fill?
 

Carultch

Senior Member
Location
Massachusetts
I was trying to figure out the conduit fill for the (2) 6/3nmb's. On another thread 6/3nmb is listed as .3318 diameter. How exactly do I do the calculation for the conduit fill?

The rule for using non-circular cable assemblies in conduit fill calculations, is to take the largest possible diameter that can encircle the cable, and treat the cable as if it were a circle of that diameter. If you intend to use SCH80 PVC, be sure to anticipate that its interior area is smaller than that of the same trade size of SCH40 PVC.

The example I've worked with is #6-6-6 SEU cable, which has a "diameter" of 0.67 inches. I treated it as if it were #2/0 RHW-2 when using my conduit sizing spreadsheet.
 

don_resqcapt19

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Location
Illinois
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retired electrician
Yes, provided it's electrical PVC and not plumbing or air-vac (which are not listed for the purpose).
While I see requirements for conduits to be listed products, I am not aware of any requirements that a sleeve be made from listed conduit.
 

infinity

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New Jersey
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Journeyman Electrician
While I see requirements for conduits to be listed products, I am not aware of any requirements that a sleeve be made from listed conduit.


I agree and there is no maximum fill for sleeves. Chapter 9, Table 1, Note 2:

(2) Table 1 applies only to complete conduit or tubing systems
and is not intended to apply to sections of conduit or tubing
used to protect exposed wiring from physical damage.
 

GoldDigger

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Placerville, CA, USA
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Retired PV System Designer
This is not true. It's the outside diameter of the pipe that differs.
You are trying to tell me that SCH40 pipe and SCH80 fittings will not interchange? I do not think so!

Schedule 40 PVC fittings have a thinner wall than the Schedule 80 PVC fittings. It is important to know that Sch 40 & 80 fittings will have the same inside diameters but different outside diameters. However, the opposite is true for PVC pipe in which the outside diameters are the same.
http://www.sprinklerwarehouse.com/PVC-Fittings-Sch-40-vs-Sch-80-s/7615.htm
 

JFletcher

Senior Member
Location
Williamsburg, VA
While I see requirements for conduits to be listed products, I am not aware of any requirements that a sleeve be made from listed conduit.

The NEC doesnt define a sleeve, however if the sleeve doesnt have to be of a listed conduit, one could get pretty crazy with sleeve materials. A straight piece of plumbing PVC, maybe okay... now add a plumbing 90 on each end.. still 8' long...still compliant? What If I have no conduit, but take a stick of straight 2" bamboo and hollow it out perfectly; still okay? Muffler pipe? Can I run a short section of garden hose to protect UF cable from house above grade penetration to trench depth? I say no, because none of those are "listed" per its chapter 1 definition.

or am I completely on the wrong line with that train of thought?
 

infinity

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Location
New Jersey
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The NEC doesnt define a sleeve, however if the sleeve doesnt have to be of a listed conduit, one could get pretty crazy with sleeve materials. A straight piece of plumbing PVC, maybe okay... now add a plumbing 90 on each end.. still 8' long...still compliant? What If I have no conduit, but take a stick of straight 2" bamboo and hollow it out perfectly; still okay? Muffler pipe? Can I run a short section of garden hose to protect UF cable from house above grade penetration to trench depth? I say no, because none of those are "listed" per its chapter 1 definition.

or am I completely on the wrong line with that train of thought?

A sleeve can be made with just about anything. You can pull NM cable through holes in wood so running the same cable through a piece of plumbing pipe would not be a problem.

From Chapter 9:

1" Sch80 nominal internal diameter: 0.936

1" Sch40 nominal internal diameter: 1.029
 

JFletcher

Senior Member
Location
Williamsburg, VA
From infinity's nested quote:

" sections of conduit or tubing used to protect exposed wiring from physical damage."

Is a sleeve, yes? Do the words "sections of conduit or tubing" mean "sections of conduit or tubing [as defined/listed in the NEC]" or "sections of conduit or tubing [or anything similar, that meet any definition of either word]"? Technically, plumbing PVC is piping, not conduit or tubing.

Bored holes in wood are mentioned several times in chapter 3 and building codes.

Not trying to be argumentative here, I just dont see where, say, plumbing PVC is allowable as a sleeve, chase, riser (in OP's case; it's penetrating multiple floors). Wouldnt 352.2 definition and 352.6 disallow such an install?
 

don_resqcapt19

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Location
Illinois
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retired electrician
...

Not trying to be argumentative here, I just dont see where, say, plumbing PVC is allowable as a sleeve, chase, riser (in OP's case; it's penetrating multiple floors). Wouldnt 352.2 definition and 352.6 disallow such an install?
And I don't see anything that says plumbing PVC is not allowable as a sleeve.
I don't see anything in 352 applying to sleeves.
 

iwire

Moderator
Staff member
Location
Massachusetts
Not trying to be argumentative here, I just dont see where, say, plumbing PVC is allowable as a sleeve, chase, riser (in OP's case; it's penetrating multiple floors). Wouldnt 352.2 definition and 352.6 disallow such an install?

I agree with Don and Rob, sleeves can be made out of anything you want. There is no requirement that a sleeve be made of listed conduit.
 
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