Is a parking canopy a "building"

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SolarPro said:
Intent may mean nothing to some of the volume posters on this forum, but it carries a lot of water in the real world. :thumbsup:
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SolarP which thing do areas adopt? The Code, the intent or the CMP comments?

The NEC is supposed to be understandable and enforceable by using the NEC. You should not expect every installer or even inspector to be going through the intent, the CMP comments etc in order to understand the code and in this case to ignore what is written in it.

I know you are very sure you are right in your interpretation and your knowledge of the intent. Well I agree with you about the intent, I disagree with your interpretation.
 
iwire said:
SolarP which thing do areas adopt? The Code, the intent or the CMP comments?

The NEC is supposed to be understandable and enforceable by using the NEC. You should not expect every installer or even inspector to be going through the intent, the CMP comments etc in order to understand the code and in this case to ignore what is written in it.

I know you are very sure you are right in your interpretation and your knowledge of the intent. Well I agree with you about the intent, I disagree with your interpretation.
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Unfortunately the NEC is not crystal clear on some important points. There are many areas where people are coming to very different interpretations based on their reading of the code and based on what they hear other people are interpreting the code to mean. Often when there are different interpretations the PV industry settles on one that wins out over the others simply by the number of people who follow it. But sometimes there are enough people following different interpretations that it causes problems. Sometimes even just a handful of AHJs with an unusual interpretation can make things difficult depending on where they are. When there are differing interpretations it can be helpful to go into the ROP and ROC documentation and get feedback from the CMP members to see what the intent was of the wording in a specific section that is not clear.

A good example of this is in 2014 NEC 690.12(5) "Equipment that performs the rapid shutdown shall be listed and identified."

Looking at the code making process and listening to the CMP members it is very clear that the intent was that equipment used in rapid shutdown needed to be listed and identified electrical equipment but that was the extent of it. Some AHJs interpreted it to mean that the equipment needed to be listed and identified specifically for use in rapid shutdown.

Some people believe that their interpretation is correct against all odds. Even if they are the only one in the USA who interprets it that way they are right and everyone else is wrong. I have talked to these people and there is no proof you can give them that they are not interpreting the code correctly. But for others who are open to a different interpretation, showing them the basis for the NEC wording can change their mind.
 
pv_n00b said:
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Looking at the code making process and listening to the CMP members it is very clear that the intent was that equipment used in rapid shutdown needed to be listed and identified electrical equipment but that was the extent of it. Some AHJs interpreted it to mean that the equipment needed to be listed and identified specifically for use in rapid shutdown.
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Those AHJs are correct. Identified is a defined term.
 
Here's the problem: there is no product safety standard for PV rapid shutdown components or systems. That was true when 690.12 was added to the Code in 2014. It is still true today.

So if you stick with that interpretation, how do you enforce 690.12? Do you defer to 90.4 and waive the requirement? Do you disallow all rooftop PV systems?

These are not particularly compelling options.

For NEC 2017, the CMP has added a requirement that rapid shutdown components are specifically listed for PV applications. But there's a reason why the language reads differently in NEC 2014 versus NEC 2017.
 
If you view the Code as a Platonic ideal, I realize that the intent and opinion of the Code-Making Panel is irrelevant to enforcement. However, this is how the person who led the working group that originally developed 690.12 describes the difference between the listing requirements in NEC 2014 vs NEC 2017:

Labeled vs. identified. The NEC 2017 requirements for “listed and labeled” rapid-shutdown equipment meaningfully revises NEC 2014, which requires “listed and identified” equipment. Article 100 defines the term identified as “suitable for the specific purpose, function, use, environment, application, and so forth.” By contrast, the definition of labeled in Article 100 “indicates compliance with appropriate standards or performance in a specified manner.” The latter is more prescriptive and narrowly defined than the former.

In practice, this means that installers can use off-the-shelf electrical components to meet NEC 2014 rapid-shutdown requirements so long as the conditions of use are consistent with the equipment ratings. For example, under NEC 2014, you could locate a contactor combiner at the edge of a PV array and use this to meet Section 690.12 as long as the combiner was rated for the outdoor environment and the PV voltage and current characteristics. NEC 2017 will require that this contactor combiner be specifically listed to a rapid-shutdown PV array standard and labeled accordingly. Revised language in 690.12(D) states: “Equipment that performs the rapid-shutdown functions, other than initiation devices such as listed disconnect switches, circuit breakers or control switches, shall be listed and labeled for providing rapid-shutdown protection.”

This is an important distinction. Some jurisdictions— including New Jersey, New Mexico and Washington—have misinterpreted NEC 2014 requirements and asked installers and vendors to prove that rapid-shutdown solutions comply with a rapid-shutdown safety standard. As of today, no such standard exists. Until the NEC 2017 is adopted, there is no requirement that equipment used for rapid shutdown be listed and labeled specifically for the rapid shutdown of PV arrays. Installers can use any listed equipment to provide rapid shutdown, so long as they field the equipment in a manner consistent with the product listing.
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Source: NEC 2017 Updates for PV Systems
 
SolarPro said:
If you view the Code as a Platonic ideal, I realize that the intent and opinion of the Code-Making Panel is irrelevant to enforcement. However, this is how the person who led the working group that originally developed 690.12 describes the difference between the listing requirements in NEC 2014 vs NEC 2017:



Source: NEC 2017 Updates for PV Systems
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So what you're saying is that it is about to get much worse; that the misinterpretation is about to be enshrined in the code. Now the equipment will have to be listed for rapid shutdown, and there's still no standard to list it too!!
 
Except that now industry stakeholders are actually working on the rapid shutdown product safety standard. If that standard isn't finished before January 2017, AHJs can simply enforce the requirements from the previous code edition per 90.4. Seems simple enough.
 
gadfly56 said:
So what you're saying is that it is about to get much worse; that the misinterpretation is about to be enshrined in the code. Now the equipment will have to be listed for rapid shutdown, and there's still no standard to list it too!!
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I could've sworn that the intention is that the equipment just has to be listed in general. And not necessarily listed specifically for rapid shutdown.

So for instance, a microinverter or AC module system already would comply, with a standard AC disconnect, and without any rapid shutdown specific equipment. Shut off the building power in general, and the module energy is limited to the input of the microinverter. And this would still comply, even if you are using modules, microinverters, and AC balance of systems components that have been kicking around in a warehouse since 2008, before rapid shutdown was even a concept.
 
Carultch said:
I could've sworn that the intention is that the equipment just has to be listed in general. And not necessarily listed specifically for rapid shutdown.

So for instance, a microinverter or AC module system already would comply, with a standard AC disconnect, and without any rapid shutdown specific equipment. Shut off the building power in general, and the module energy is limited to the input of the microinverter. And this would still comply, even if you are using modules, microinverters, and AC balance of systems components that have been kicking around in a warehouse since 2008, before rapid shutdown was even a concept.
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Well if you can read this:

"Revised language in 690.12(D) states: “Equipment that performs the rapid-shutdown functions, other than initiation devices such as listed disconnect switches, circuit breakers or control switches, shall be listed and labeled for providing rapid-shutdown protection.”

as meaning something different I'm all ears as to your explanation.
 
pv_n00b said:
Some people believe that their interpretation is correct against all odds. Even if they are the only one in the USA who interprets it that way they are right and everyone else is wrong. I have talked to these people and there is no proof you can give them that they are not interpreting the code correctly. But for others who are open to a different interpretation, showing them the basis for the NEC wording can change their mind.
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But not you right? :)

Again I do not disagree with you about what the submitter's intent was.

But intent is not enforceable, only the adopted words are the code and regardless of how well you know the intent it does not change the adopted code.
 
iwire said:
But not you right? :)

Again I do not disagree with you about what the submitter's intent was.

But intent is not enforceable, only the adopted words are the code and regardless of how well you know the intent it does not change the adopted code.
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I don't think that's quite right. Let's say you and the AHJ are at loggerheads on some issue, and it's a really big-dollar issue and you want to go to the construction board of appeals. In that venue, introducing the comments or even personal correspondence with members of the CMP would be very germane in determining the outcome. These are, after all, consensus standards. It matters what the consensus makers thought they were trying to do. Even in the civil/criminal court system, the courts look to the intent of the legislature in drafting the statute(s) under review, considering the debate and commentary as an essential element in making their decision.
 
In court they would have to go with the adopted wording not the intent.

Might as well toss the code book in the trash if it is to be overuled or ignored.

If the issue is that critical the NFPA has ways to deal with it
 
The question of intent is relevant when there is ambiguity, but not when the words unambiguously go against the intent. Each AHJ has a certain amount of freedom to approve things that go against the wording but match the intent, but that approval does not change the meaning of the words.
They are not AFAIK allowed to reject something that matches the words.
 
GoldDigger said:
The question of intent is relevant when there is ambiguity, but not when the words unambiguously go against the intent. Each AHJ has a certain amount of freedom to approve things that go against the wording but match the intent, but that approval does not change the meaning of the words.
They are not AFAIK allowed to reject something that matches the words.
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That is a much better way to describe it and I agree
 
Going back to the OP. Apparently this precise topic is among the items covered in the latest Code Corner in Home Power:

Building or Structure?

The NEC definition of structure is broad: “that which is built or constructed;” a building is defined as a “structure that stands alone or that is cut off from adjoining structures by fire walls with all openings therein protected by approved fire doors.” This could be a house (a dwelling), garage, office building, factory, or retail space, but not a carport or freestanding gazebo. A building is a structure, but not all structures are buildings.

This matters because Section 690.56 requires a label identifying power sources and indicating the location of the PV system disconnecting means when PV systems are on either a building or a structure, thus applying, for example, to both a home or a carport. However, the rapid shutdown requirements of 690.12 apply only to PV systems on buildings—and thus do not apply to a carport or ground-mounted system. The 690.31(G) requirement for DC circuits to be in a metal raceway or type MC applies to circuits inside both buildings and structures. And a big change in the 2014 NEC was the removal of “on or penetrating a building” from Section 690.11, effectively extending DC arc-fault protection to all PV systems.
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I realize that this opinion won't change any minds here. But it's an unsolicited interpretation.
 
Home Power said:
. . . A building is a structure, but not all structures are buildings.
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Bad logic, as previously discussed. Under the 2014 NEC definitions, a building is part of a structure, and every structure is one or more buildings.

Cheers, Wayne
 
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