ECN Forum Forums Code Related Discussion NEC & other Code issues Fixture Temp rating...

I do not have the statistics concerning fires caused by overheated light outlets. They are available from the NFPA Records Department.
I do have the statistics of fire cause at switch and receptacle outlets, with the wood framing member being the first material ignited.
I wrote letters expressing my concern about gaps between outlet boxes and combustible material, allowing fire to be communicated to the stud. The response was; the code was changed from no gap allowed to the present allowance of 1/8 inch. To me, this was a step backwards. My understanding is, the proposals were from the sheetrock installation lobbyists, to allow router cuts.
I tried to get the State Building codes to address this issue, it was sandbagged.
The local Fire Marshall was not aware of the statistics.
Protection at light fixture outlets will be strictly a design issue and should be observed, by all the installers, in a common sense manner.
Install some form of heat shield between the lamps and the outlet boxes. Maybe we need to apply "Space Shuttle" technology.

Bennie,

I am under the impression that the solution is not as simple as a shield. If it was I think We would see them on the market right away. I think the concern involves the heat travelling up the wire (would convection be the right word) and that it may even affect wiring before or past the Jbox.

I am not familiar with the workings of UL. Is there a way We can get more info on this? I mean on the test conditions and results?
I am suspecting that this 'blanket' warning is really for worst-case situations such as areas with an attic above and covered with insulation. It would be nice to know that a location between floors with no insulation and 75C wiring is OK. Or maybe they think it's too complicated for us to remember?


Bill

Now! I think I understand. I was going the wrong direction.
I did not even consider the heat from the lampholder heating the wires. That is very resonable, and conceivable.
This does put a new spin on the problem. It appears that no incandescent light fixture would be safe with 60º insulation.
Most of my fixtures are flourescent, even though I have replaced all the old wire in my house.

I ran off some rough calculations in sizing heat sinks for SCR's. It is within our technology to install the lampholder in a heat sink, and limit the temperature of the conductors to an acceptable level.
The down side is, it would be the ugliest fixture in the world.
I have no figures as to cost. Maybe some interior designer could develop a creation that includes the heat sinks, for cosmetic considerations.

better off ugly & safe....

i was messin round with an IC can today and got to wondering if that little thermal cutout could be used as an isolated sort of "device" to be stashed in an old 60 deg NM box.???

Does anyone know of any 'Approved' methods of dealing with this until your new products hit the market?

Or any info on the how fixtures are tested?

Bill

Bill;
i'm at a loss as to who to ask...



sorry!

One remedy may be to throw away all incandescant lamps, replace with the modular flourescent units.
Home Base Stores are all closing in Oregon, and Washington. I am going to the liquidation sale and stock up on these units.
The two items that have never changed, in our manufacturing system, since the beginning, is the Edison base lamp, and the oil level dip stick in my car. A Rolls Royce has the same design of dip stick as my '79 Pinto.

Bennie,

If those (going out of business) Building Supply Stores are operated like the few locally, TAKE LOTS OF MONEY WITH YOU .

They seem to jack up the price and then post 50% to 70% off signs all over the place.

But just go down the street to the store still in business and the price of the same item is less than the 50% to 70% off price.

Glenn