1. 680.23(B)(2)(b) requires an INSULATED #8 conductor to be run in the conduit between the forming shell of a wet niche pool light to the junction box.

Question: What is the reasoning for the #8 to be installed within the conduit and why must it be insulated?

2. 680.24(B) permits a pool light transformer enclosure to connect directly to the conduit extending to the forming shell without a listed pool light j-box. Many, including the common Intermatic transformer, are marked as suitable for direct connection to the pool light.

Question: How do the typical transformer enclosures comply with 680.24(B)(1)(1)? A standard RNC terminal adaptor and locknut isn't considered a "hub" is it?

1. The insulation provides corrosion protection. The end of the wire and the lug is also required to be "potted" using a listed compound made for the purpose.

2. I believe the "hub" language is left over from when the raceway to the light was brass.
At this point, with RNC, the only function is to be somewhat rain tight. There is no electrical connection involved.

Bryan
1. Corrosion protection.
2. You are correct that a terminal adapter is not a hub. The transformer enclosure must comply with 680.24(b). The transformer has a duel listing CSA, and UL. The listing "suitable for direct connection" is a CSA listing and does not apply in the US. Although the transformer enclosure has a UL listing, UL does not list it for direct connection. I understand that the manufacturer has a bolt on hub kit that may be field installed to comply with code.

What is the benefit of a hub if you are using RNC?
I can understand it if the raceway is the grounding path but that is the 8ga when RNC is used.
I think this is just a glitch that has not been fixed yet.

Enclosure support.

I would not accept a transformer that was only supported by two RNC raceways and cite 352.10(H).
I'm holding an Intermatic PX300 in my hand and I am not sure how it complies with 680.24(B)(1)(2) in the first place. The can is steel.
It weighs about 15 pounds so I would never accept a PVC raceway(s) alone to support it

This is an interesting question that I never really investigated but I think we have the answer. They still need a listed J box if they are using this type of transformer because of the 680.24(B)(2)(1) problem so even if they did bolt on a hub it still would not be legal. I guess that is why these things are usually hanging on the wall and piped to the J box. The ones I see that have been around a while are usually rusty too.
The low voltage severly limits the length of the run too,making it harder to keep them inside (unless you go to some fat wire).

First off 352.10(h) doesn't apply. The enclosure is not a conduit body.

314.23(e) & (f) permits it.

The new bolt on hub kits are listed by ul for the application. But you are correct if they do not use the listed kit by the manufacturer than they will need a j-box listed for the application.

Mike, that is the point. A conduit body is the only thing you can support on RNC. Certainly not a 10-15 pound transformer/enclosure. (ref the "device support post)

A listed hub kit will still not make the case of the transformer "comprised of copper, brass, suitable plastic, or other approved corrosion-resistant material".

If it is a steel enclosed transformer it can't be directly connected.

BTW the real reference is 352.12(B) but that gets you back to 352.10(H)

As I said, (2005 NEC )314.23(e) & (f) permits it. That code section permits enclosures to be supported by 2 conduits, as long as the conduit termination is with a hub or threaded entry.

Exception: One conduit for support is permitted if it is RMC or IMC and the enclosure is no more than 20lbs.

Thanks guys. I've sent off an email to Mark Ode to get his opinion on the matter, but you both have confirmed my interpretation of the issue.

Mike how do you get past 352.12(B) "Uses NOT Permitted"?
"Not permitted" sounds pretty binding to me.
We were talking about RNC, not RMC or IMC

Because that code section is for light fixtures or conduit bodies that support fixtures. RNC is not permitted to support those items. There is nothing in 352 that prohibits RNC to support a box or enclosure.

So the section in 352 does not apply to boxes or enclosures. If it did you could not permit the approved swimming pool J-box to be supported by RNC either, but that is approved all over Florida and the US every day.

The support of enclosures falls in article 314 as I said. There are specific requirements to follow and exceptions.

352.12 Uses Not Permitted.
RNC shall not be used in the following locations.
...
(B) Support of Luminaires (Fixtures). For the support of luminaires (fixtures) or other equipment not described in 352.10(H).

I read this to say you can NOT use RNC to support anything except "... nonmetallic conduit bodies not larger than the largest trade size of an entering raceway. The conduit bodies shall not contain devices or support luminaires (fixtures) or other equipment."

The article does say <TNC shall not support> "other equipment not described in 352.10(H)."

I understand they allow the J box on RNC but usually there is also a rickety board it is tied to. It is still technically illegal. I would draw the line on a 10-15 pound transformer. In a month in the sun it would be laying on the ground and the pool water would be flowing out of the can.

But I guess we are not supposed to care what happens the day after the CO.
I do and I would be prepared to defend my call. After all we are just ignoring the j box violation. I certainly am not out of line on the transformer.
At my house the j boxes are supported by the wall where they are mounted.

I stand corrected! I looked into the subject some more and you are 100% correct! I found some info in the IAEI One and Two Family Dwellings Electrical System book that supports your statement.

Since that is the case I assume that from now on the swimming pool junction box will have to be supported (not the conduit but actually the box will have to be attached to something). Man that will cause some problems!

Things like plastic bushings, fittings (TA male connectors) and such, also fall under the definition of the term equipment in article 100. Therefore if we were to sleeve a uf cable through RNC for protection as it comes out of the ground than the TA connector and plastic bushing used at the end of the RNC for protection will have to be supported in addition of the conduit, (since they are equipment), and RNC is not permitted to support equipment. Havn't figured out how we can do that yet?

We sure are in trouble!

I think we ignore the plastic J box hanging up there on the RNC because it doesn't really weigh any more than a conduit body and it seems pretty safe although I still like to see some support. Usually it ends up being a 1x3 PT "window buck" scrap they found in the dumpster.
I would certainly want some independant support for a transformer tho.
Usually this is a moot point since a regular steel cased transformer would not qualify for direct connection anyway, even if it did have a hub. I suppose there are plastic cased transformers that would meet the letter of the code and a stainless transformer can would probably get "approved". per 680.24(A)(1)(2)

How and when do we ignore the code, and permit or not permit something? If it all doesn't meet code do we not reject it all?

Think about it..if they meet the minimum requirements in the code they did the worse job they can do .....not the better.....but if they don't even meet the worse?

Opinions?

Doesn't 314.23(E) come into play here?

Well Bryan that's what I thought....please read all the other post's and give us your expert opinion.

What say you Nick?

I could be wrong but I thought xxx.12 rules of things that are not permitted uses trump the other general articles.

I've read the other posts and have had this very discussion on other forums in the past. In my opinion, sometimes the exact wording of sections creates unintended consequences that were not conceived of before the wording was finalized in the code.

In these cases, common sense and good judgment on the part of the AHJ must be made to determine what installations are suitable or not based on conflicting information provided by the code or other recognized standards.

I popped this up over on ECN and they asked how can you make RNC "wrench tight"? so 314 must only refer to IMC or RMC.
352.12(b),<shall not be used to support> also says "... or other equipment not described in 352.10(H)."
That would exclude anything BUT a conduit body.
I understand this brings up an interesting problem since there is no real way to support a "deck box" that is not in a deck. ... unless we want to call it a conduit body

Since is is not a FS, FD, "cast" or "sheet metal" that might not be to far a stretch. There is sufficient space for the splices.

Bryan I agree common sense says the J box is probably not going to be a probl;em only supported by the RNC. My original objection was to hanging the transformer up there, only supported by RNC. It was after really looking that the actual language became troublesome.