ECN Forum Forums Code Related Discussion NEC & other Code issues Conductors rated 125C

Mil-spec shipboard cable can easily handle those temperatures and conditions. Unfortunately, NEC is silent so far as allowing them in structures, but they exceed code in every way and I'd bet your local local building inspectors would allow use if you ask up-front.

I think you need to talk to the manufacturer for as clarification on the instructions. I looked on the web site and I am not sure which light you have but the 125c part can't be far from the ballast. You should be able to use THWN for the circuit conductor beyond the hot spot.

Thanks for the feedback gfretwell.

I have contacted Hadco for tech assistance and they haven't an answer for me yet...in 3 days mind you...

You see...I don't see a answer myself.

These inground 175 MH fixtures feed directly into the fixture beneath the ballast...so where am I supposed to transition to THWN?

If I were to have a handhole 2 feet away...what would I use underground for the supply conductors from the fixture to the handhole?

There is NOT a conductor listed for the wet location except MI at above 90C in table 310.13...?

shortcircuit

The distance that the supply conductors need to be rated 125°C will still be an issue.
The PVC conduit is rated at 90°C, isn't it?

Short:
Another ltg mfg provides a 'shield' /'sleeve' to slip over your supply conductors entering the ballast compartment area.

Kind of looks like a mini chineese finger that you slip over your THHN. We also had to use it on some conductors for some machines that I worked on.

IF anybody has it now, probably McMaster Carr.

John

Thanks for the ideas guys. I'll talk to the manufacturer about the sleeves today Hotline1...

I am feeding the fixtures underground with PVC and changing to K-flex (LFNC) within 3ft for flexibility. I didn't want to install a handhole.

The label on the fixture only states the supply conductors need to be rated 125C electure.

The conduit entry into the fixture has to be sealed with a sealing compound that is provided with the fixture (3M 8882 encapsulant)

shortcircuit

Could you close nipple an FS box to the fixture and transition there?

Can I bury a FS box in the ground?

I guess it depends on the box. It this point we are just shooting in the dark. I think you need Hadco to tell you just exactly how you are supposed to install these things. It is their labelling that got us here in the first place. As in inspector I would certainly try to find a solution that didn't require you to come up with a spool of "Unobtainium" wire.

This thread raises an interesting question about a wet location rating.

Normally any underground location is considered a wet location.

But if you have a heat source that can actually heat the wire up to 125C, then it is quite unlikely that the wire will actually be wet In essence, the wire will be baked dry by the light.

So is this a wet location or not? It might very well be wet when the light is off, but dry by the time the temperature exceeds the wet rating of the wire

-Jon