Min. 90C Supply Conductors

[DBoone]

Multi-part question

1.) is this a requirement because of the heat that the light puts off

2.) is the insulation that comes with some fixtures (between the top of the housing and the ceiling) there to help protect the junction box wires from the full effects of the heat from the light.

3.) do LEDs take away the risk of overheating and degrading supply conductor insulation

4.) what code section lists the length one must cut back and splice on a 90C cable

 

[Buck Parrish]

1) yes
2)yes, Every body that has worked on a older rental home has probably seen insulation on wires get brittle due to the heat.
3)NS
4)NS

 

[user 100]

4.) what code section lists the length one must cut back and splice on a 90C cable

See 410.117(C) in the '17

 

[JFletcher]

See 410.117(C) in the '17

For those that do not have the 2017 NEC could you list the distance please?

As for the original posters question number 3, no LEDs do not take away the risk... Not completely anyway

 

[user 100]

See 410.117(C) in the '17

For those that do not have the 2017 NEC could you list the distance please?

410.117(C)

Tap Conductors:

"Tap conductors suitable of a type for the temperature encountered shall be permitted
to run from the luminaire terminal connection to an outlet box placed at least 300mm (1ft) from the luminaire.
Such tap conductors shall be in suitable raceway or type AC or MC cable of at least 450mm (18 in.) but not more than 1.8 m (6 ft) in length."

 

[infinity]

4.) what code section lists the length one must cut back and splice on a 90C cable

Since these are branch circuit conductors there really is no minimum distance in the NEC. If you're using tap conductors then 410.117(C) would apply. 410.117(C) might be a good guideline to follow when extending the branch circuit.

 

[user 100]

Since these are branch circuit conductors there really is no minimum distance in the NEC. If you're using tap conductors then 410.117(C) would apply. 410.117(C) might be a good guideline to follow when extending the branch circuit.

^^^^^^
This

I should have clarified that point for the op- that is just about the only thing that comes close when running into this issue, and
is only a template- there is no such req for BC conductors.

OP: Generally speaking, the new piece of nmb is app 24" long- the new jbox is about a foot away from the light, with 6" of the new wire in jbox and
6" in existing ceiling box.

 

[Dennis Alwon]

There is no distance to worry about, as long as the wires going to the jb for the fixture are rated 90C

 

[DBoone]

Thanks everyone.