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It is really up to the inspector.

If the inspector feels that a cable would be subject to damage they may require more.
 
GerryB said:
Thanks for replies. Kept hearing no more pvc but couldn't find anything.

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No problem but still up to the inspector, if the inspector feels the PVC is 'in areas of physical damage' then the inspector could prohibit the use of standard schedule 40 PVC.

352.10(F) Exposed. PVC conduit shall be permitted for exposed
work. PVC conduit used exposed in areas of physical damage
shall be identified for the use.

Informational Note: PVC Conduit, Type Schedule 80, is
identified for areas of physical damage.
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PVC also has to be suitable for the temperature in the location used, which may be an issue on a rooftop. PVC on rooftops for solar is not a good practice in my opinion, although with the right PVC it may be technically code compliant.
 
jaggedben said:
PVC also has to be suitable for the temperature in the location used, which may be an issue on a rooftop. PVC on rooftops for solar is not a good practice in my opinion, although with the right PVC it may be technically code compliant.
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CPVC would be OK for temperatures, but I don't know if any is out there listed for electrical and UV-stabilized.
 
Per UL white book it sounds like only sch 80 is listed to be used when subject to physical damage.

The marking ‘‘Schedule 80 PVC’’ identifies conduit suitable for use where exposed to physical damage and for installation on poles in accordance with the NEC.
 
electrofelon said:
I see it, potentially, a bit differently. Being that this question is in the PV forum, we should ask if this installation is covered in 690.31(G). IF so, PVC would be specifically disallowed.
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The OP did say 'up the outside of a house', or else I would have brought that up.
 
electrofelon said:
Is your take that only the raceway portion inside a building is subject to the metal raceway requirement in (G)? I see it as confusing and unclear since they added the "on or" words in the title.......
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I'll be back to check after ten or twenty pages on the subject to find out what gets determined, this is interesting to me. Enjoy the hashing out . I have a granddaughter now, I am baby sitting this evening.
 
electrofelon said:
Is your take that only the raceway portion inside a building is subject to the metal raceway requirement in (G)? I see it as confusing and unclear since they added the "on or" words in the title.......
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The title 'in or on' applies variously to different parts of the whole section, notably subsections (1), (3) and (4). (Section 2 implicitly applies only inside buildings.) The metal raceway requirement is contained in a sentence that says only 'inside a building'.

I would agree the organization of the section is confusing. The first paragraph probably ought to have been subsection (1). But I don't think the language of the metal raceway requirement is unclear. The sentence begins with 'Where' and doesn't say 'on.'
 
jaggedben said:
The title 'in or on' applies variously to different parts of the whole section, notably subsections (1), (3) and (4). (Section 2 implicitly applies only inside buildings.) The metal raceway requirement is contained in a sentence that says only 'inside a building'.

I would agree the organization of the section is confusing. The first paragraph probably ought to have been subsection (1). But I don't think the language of the metal raceway requirement is unclear. The sentence begins with 'Where' and doesn't say 'on.'
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Ok I see. Yes it should be organized differently. To me, the Bold title should be separate and the "inside conduit must be metal" phrasing should be in a
(new) numbered subcategory. Otherwise, the "on or" qualifier carries over to the next sentence. I am no English major, but that is my take :)
 
electrofelon said:
Ok I see. Yes it should be organized differently. To me, the Bold title should be separate and the "inside conduit must be metal" phrasing should be in a
(new) numbered subcategory. Otherwise, the "on or" qualifier carries over to the next sentence. I am no English major, but that is my take :)
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Actually, there is no logical problem with a set of rules that as a group covers two different situations and yet contains one or more rules that explicitly apply to only one of the two.

Example:
"I am going to talk about A and B.
When you have A or B do this.
When you have just A, also do that.
When you have just B, also do some other thing."


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Yes, I think that "on or " is where the confusion is coming from. We just went from the 2011 to the 2014 here in Ct. on Oct 1. What I have seen is some installers, like SolarCity, run all EMT. Others do a combination, but some were saying after Oct 1, no more pvc. A quick reading of 690.31(G) would seem to say that, but I agree it actually doesn't, which makes you wonder why they even added those "two little words".
 
GoldDigger said:
Actually, there is no logical problem with a set of rules that as a group covers two different situations and yet contains one or more rules that explicitly apply to only one of the two.

Example:
"I am going to talk about A and B.
When you have A or B do this.
When you have just A, also do that.
When you have just B, also do some other thing."


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Sure, but I find (G) not laid out in a logical format like your example is. They lay out some requirements, and then lay out some more requirements that is grouped in organized numbered lists.
 
GerryB said:
Yes, I think that "on or " is where the confusion is coming from. We just went from the 2011 to the 2014 here in Ct. on Oct 1. What I have seen is some installers, like SolarCity, run all EMT. Others do a combination, but some were saying after Oct 1, no more pvc. A quick reading of 690.31(G) would seem to say that, but I agree it actually doesn't, which makes you wonder why they even added those "two little words".
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Yes, the way I read it the first few times was kinda like this: "if a DC PV circuit enters a building, the circuit shall be contained in metal raceway." I agree with careful reading, and in particular reading ALL of (G) and realizing why the "on or" is there, we can conclude that only the inside portion needs a metal raceway.
 
jaggedben said:
The title 'in or on' applies variously to different parts of the whole section, notably subsections (1), (3) and (4). (Section 2 implicitly applies only inside buildings.) The metal raceway requirement is contained in a sentence that says only 'inside a building'.

I would agree the organization of the section is confusing. The first paragraph probably ought to have been subsection (1). But I don't think the language of the metal raceway requirement is unclear. The sentence begins with 'Where' and doesn't say 'on.'
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Agreed. For many cycles now, the Code has required metal raceways and similar for dc PV circuits inside a building, largely to protect these conductors against inadvertent damage where their path is not visible. (Say when a firefighter is ventilating a roof.) That is also the logic for marking where these conductors are embedded in building surfaces.

But exposed outside the building, those circuits are easy to trace. So the metal only requirements do not apply. The obvious example is where you have exposed single-conductor cables in free air. PVC is most common in rooftop applications in coastal environments, where metal conduit simply won't last. But you can use it more generally. (I wouldn't use it on the outside of my house, but I'm getting ready to put a bunch of it underground and it sure is cost effective.)

The title of 690.31(G) may have changes in NEC 2014, but the intent hasn't changed in so far as where metal is or isn't required. It is required specifically where dc PV circuits are run inside a building or structure. jaggedben is reading this correctly.
 
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