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.