To be connected to 90 deg c wire only

[Fred B]

A lighting fixture marked "To be connected to 90^o C wire only". House wired with old NM 60^o C cable. I understand the immediate concern of heat generated at the fixture can compromise the wire integrity, but is there additional concern up/down stream from fixture of the use of the older NM with this fixture? There is easy access locally to the fixture box to add a jbox and splice a line of a NM-B wire into the fixture box replacing a short section of wire, would that be an appropriate fix? Or are there other considerations? My understanding is the NM-B wire is 90^o C even though conductors are not marked individually as such NEC 334.112.

 

[infinity]

I've done many of those over the years where the old AC or NM cable was dried out. If there was an attic above cut back 2' of the AC cable, install a box and run NM to the ceiling outlet. If there was no access from above we would ask if they wanted a medallion above the fixture then we would cut in and hide the new box behind the medallion.

 

[don_resqcapt19]

There is no additional concern once you are away from the heat produced by the light.

 

[roger]

In reality it's simply a CYA for the fixture manufacturer more than the older wiring being an actual problem.

Roger

 

[Fred B]

In reality it's simply a CYA for the fixture manufacturer more than the older wiring is an actual problem.

Roger

I have seen extreme degradation of an older wire from fixture heat, either over sized bulb, or thermal barrier being damaged or removed on a light fixture. New fixture has no thermal barrier.
Additional question would be, what effect on AFCI requirements would splicing in a section of NM-B have, would an AFCI need to be added or exempt as long as I limit the added wire length?

 

[LarryFine]

If the light says to "connect only to 90-deg wire," and not "install only on boxes containing 90-deg wire," why wouldn't using pigtails made with 90-deg wire be technically compliant?

 

[roger]

I have seen extreme degradation of an older wire from fixture heat, either over sized bulb, or thermal barrier being damaged or removed on a light fixture.

As we all have, but a chandelier or any hanging type fixture will not be an issue with heat from a lamp yet most have the same wording. The problem with older brittle insulation is the same whether you are hanging a new fixture or trying to splice new conductors to it.

Roger

 

[roger]

If the light says to "connect only to 90-deg wire," and not "install only on boxes containing 90-deg wire," why wouldn't using pigtails made with 90-deg wire be technically compliant?

It would be.

Roger

 

[LarryFine]

It would be.

Seems silly because I'm sure most heat in the box comes from the light, but not through the wire.

I have replaced brittle insulation with insulation stripped from scrap wire; sometimes up one size.

 

[winnie]

I have replaced brittle insulation with insulation stripped from scrap wire; sometimes up one size.

DIY report but I like this material for that use:

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Jon