What is a good method of installing new light fixtures that to older wiring?

These new fixtures have instructions that say that the conductor temp rating must be of a certain caliber, and that older NM may not comply...???

Sparky: I am also curious of the reason the fixtures are limited to 90º wire. I know that the older NM cable had TW 60º wires.
I have never read the history, or reason for 60º wire not being acceptable. Many homeowners can not tell the difference. This appears to me, to be an irresponsible development.
I hope someone can give the technical reasons for this application.

Bennie, Sparky,

Let me toss in an article I found over at IAEI Website that may answer your question (They gave permission to reprint) Then let me know what you think.

https://www.electrical-contractor.net/Need_To_Know/incandescent_fixture_dangers.htm

Bill

[This message has been edited by Bill Addiss (edited 03-24-2001).]

well....
apparently it's all about captive heat affecting conductors of the feeding outlet box. The articles focus is on incandesant lighting. The article mentions 410-11.

The obvious being that a hanging, or open shade fixture will dissapate the elements heat better than a closed shade cieling mounted fixture.

It is somewhat an irresponsible develpoment Ben, being that changing out a fixture is a DIY'ers usual gig. The instructions hit the round file with little consideration.

It also makes it hard on the serious field electrician, trying to explain to customers that their house wiring is NFG for any walmart fixture mama likes. I am viewed as a "carpetbagger" in those deals....


The only "code" fix is to change the wiring to 90 NM, other threads suggest the "floater" box in the cieling. This is really two wrongs trying to add to a right.

There is no gauge or exception allowing added insulation, or displacement of conductors to a defined distance as in a larger JB with pigtails,or AFCI's, or lesser elements ( would'nt last anyway).

Why market a no-win situation?

My reading of this is that the problem arises because of the increased insulation being added to older houses. I don't think that fixture design has changed really, meaning that the existing fixtures are also a problem. I was not able to find any other mention of this problem except for that IAEI article. It seems like these warnings have crept up on all light fixtures recently and no one talks about it?

Bill

Sparky: We are in full agreement, I hope this opinion is not restricted to only us.
I would prefer to have a light fixture constructed in such a manner, that heat would be prevented from commuting to the outlet box and wiring. I am sure I can do this, and others are much more intelligent than I.
As you have stated, this appears like a liability disclaimer to prevent litigation.
In my service work days, I had a lot of creamated wire problems in fixture outlets.
This increased after the banning of asbestos.
Many were injured and had there lives shortened by asbestos exposure. This is a documented fact. How many fatalities and injuries are a result of fires in these overheated outlet boxes, that asbestos insulation would have prevented? This, we will never know.

Bill,
the article does mention construction insulation being a factor, i meant adding insulation bettween fixture & outlet box, as a means of protecting overheating of old NM.

Ben;
I'm sure heat dissapation could be addressed in a fixture. I'll never be on the dean's list, but even i could choke up an idea or two...

try this;

A 3" thick circular spacer made of non-flammable insulative material , to be installed bettween fixtures that require 90 deg wire, and old 60 deg NM. NRTL approved.

This again appears to be the old backward approach to hazard prevention, and my old pet gripe.
Dealing with the effects of a problem and not focusing on the cause.
I have some old pieces of asbestos sheets. These belonged to my father. He was a plumber, and often repaired copper water lines. He used these sheets to prevent ignition of the wood framing members, when soldering the connections.
I used these recently, and noticed that on one side the temperature was very high. The other side would not melt butter.
Unfortunately there has not been a material created that compares to this degree of heat insulation, but I know an acceptable material using proper clearance can be used to make all fixtures safe, even to compensate for higher wattage lamps being installed.
I recently watched a hanging chandelier break into flames when first turned on, the first thing ignited was the UL label, the second was the "Made in China" decal.

2 wrongs don't make a right , i stand corrected here Ben.
I would have mentioned asbestos, except it gives everybody a bad case of rectal lightning these days.

Not long ago, i has a job where the customer supplied the cheapest lighting he could get, all show, no go.
One such item was an IC/NON-IC recessed can, the instructions stating that if i simply scrapped off the(IC/NON-IC) sticker, it would become IC rated.
I had complained to the GC, and he said as long as the UL sticker was visible after the fire I need not worry.





[This message has been edited by sparky (edited 03-25-2001).]

Glad to see my original question was not so naive after all. There seems to be some real debate about how to best insure against heat damage with these high-temp fixtures. It is absolutely true (as Sparky said) that most homeowners would not give a second thought to putting in recessed lighting. I think there's an unfortunate sentiment that goes something like "if it wasn't safe for me to do they would sell it at Home Depot".

I don't know if this is a recent innovation or not, but most halogen fixtures do have a temperature cutoff whereby they begin to flicker and ultimately cut out when some critical temperature is reached (what that is I don't know). Perhaps this is the manufacturers response to the changes in insulation methods? In any case, it seems that the issue is not so black and white.

-TRS

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

I have a book from around 1989 that addresses this issue. It is called "Handbook of Practical Electrical Design"by Joe & Brian Mcpartland(Joe was well known back then as an authority on Electrical Systems, I wonder what became of him or Brian. Anybody?)It is common practice to splice a short piece of 90C cable, which could include "Romex" NM-B,(the suffix "-B" indicates 90C conductors. NM cable manufactured after 1985 is type NM-B) to the old cable and stick the j.b. into the ceiling(a "throw-away" or "floater")ahead of the fixture.
[This message has been edited by Redsy (edited 03-29-2001).]

[This message has been edited by Redsy (edited 03-29-2001).]

The floater concept, appears to be one solution, for a degree of protection.
Unfortunately this will not be widely known by most homeowners.
This is again, the trend to deal with the effect, and not addressing the cause.
There is many more residential occupancies that have 60º insulated wires, than 90º.
I only hope it is not an epidemic of home fire causes.
I feel the manufacturing industry can provide a solution, to preventing the cause.

While we are on the subject, the popularity of retro-fitting recessed incandescent fixtures, especially with regard DIYers, presents a few other headaches. Even with electronic stud sensors, you may not detect a pipe that is a few inches back from the ceiling until you cut your hole... oops! Then there is the issue of using the connection box to loop through to other similar fixtures on the same circuit. Some of the cheaper fixtures have the box mounted directly on top of the housing, and although I've seen it done, I dont believe you are supposed to use this box as a junction to feed other fixtures. In the absence of explicit permission printed directly on the cover to do so, along with the # of additional conductors allowed, I think this is a violation. There is also the issue of a homeowner not understanding IC designations or clearances from combustible material.

Redsy brings up an interesting question regarding these fixtures witht the box mounted on top of the fixture. These boxes really are fairly small (and close to the heat source), but there is no statement regarding how many wires it can accomodate. Assuming that Redsy is right and these fixtures cannot, by code, be daisy-chained to others, it would render these fixtures relatively useless since it is the rare circumstance that a single fixture is to be installed. I, most homeowners, and I would bet some electricians, would assume that they were designed to accept one feed in and one feed out. If this an erroneous assumption, better that I find out now than later. Any more opinions on this?

-TRS

There just does not seem to be a generic all round, good for all fix to this. It seems somewhat unfair that the manufacturing sector leaves it to the trade, or whoever actually reads the specifics. Some good suggestions and points of view here however, much appreciated.

The "Floater" solution that Redsy mentions is the only 'acceptable' method I've heard so far. Perhaps the worst part is that only a relatively few people are aware of the problem. Even though the Warning is printed on the box I've yet to find a Consumer that has actually read it.

As Sparky had mentioned, it seems to be a no-win situation for the Electrician.

Bill

I admit to using the floater approach on a couple of fixture changeouts for the few Residential service type jobs I have done [other than family and friends].

I tried as much as possible to put the J-Box's outlet for the change from 60 degree NM to 90 deg. NM, in a location that was not so visiable - trying to give it some degree of hiding, rather than sticking out like a sore thumb!
All the ones I did were fortunatly in an attic space, rather than something like a shallow soffit, or 1st floor ceiling, so there was some room to work around.
The end result of having the 1 gang blank cover on the J-Box was not too bad, plus these customers understood the entire reason for it.

After reading the ideas in this thread, I was also pondering some techniques for recessed Incandescent fixtures, which will limit their potentials for fires.
Asbestos, or glass braiding Insulations [both on the conductors and the fixture it's self] would be one step, but the conductor's heat sinking would be overcome with Aluminum wire.
I don't exactly like Al, but it won't heat sink like Cu or Ag [Silver].

This temperature situation has been a consern in Fluorescent lighting for quite some time [90 deg. Insulation within X inches of the ballast], so why did it take the companies so long to require the recessed fixtures this also??
I know very little of legalistic stuff - please pardon my ignorance

On a semi-related issue, I had the task of rewiring a high intensity tanning bed once, for a good customer that owned the tanning salon. I hooked up all kinds of tanning beds for him at this salon - we learned a lot from each other, too!!

The High Intensity unit had five [5] 2,000 watt HID lamps in the top [only the ballasts, capacitors, contactors, control equipment and unit subpanel was in the bottom].
The original wiring in the top used insulation similar to that used on Ballasts and Transformers [TEW, I think] - something like a max. temp. of 100 + degrees Celcius.

These conductors began to fail after 6 months of normal usage. Failure was a result of the insulation becoming "dried out" and brittle from the high levels of unfiltered UV light available, rather than just the ambient temperature it's self. When the top unit was raised / lowered as a person used the machine, it would move the conductors and create cracks in the insulation. When the lamps were first started, they were pulsed with a 2.5KV series of pulses, just as HPS lamps are. The ignitors are remote from the lamps, and in the case of this unit, they were in the lower section near the Ballasts.

Needless to say, the cracked insulation only allowed the ignition pulses to flow out through the cracked insulation.
Visible history showed that random starting was achieved over the time that the insulation's breakdown was the newest.
After repeated events, the insulation failure became too great, which kept the ignition pulses at the cracked points closest to the grounded frame. At these points, the ignition pulses would work on the conductor until there was a direct contact to the grounded frame. This would not appear as a short circuit since it was on the output of the Reactor type Ballasts.
One by one, the lamps failed to work, until they all quit. That's when I was called in.

The end results were using Glass Braided high temp silicone insulated conductors in the top part, relocating the ignitors to the top, sending the Ballasts [Reactors with intregal Autotransformers wound to the cores] out to be rewound a repotted - they had signs of overuse, resulting in charred terminals and windings.

This was an invaluable lesson to me and the client.

BTW: The company that made the unit had no knowledge of this occuring, as this was kind of a "Prototype" unit. They were so glad to be informed of this by us, that they sent reps and design engineers to the site to help with everything plus expand on the situation.

P.S. They paid for all expenses on our end!

Scott SET

Scott,

Thanks for your comments. It has been fairly well understood about reccesed lighting having an issue with heat. What is less well known is that standard ceiling mount fixtures have a problem with it too, especially where there is an Attic above.

Bill

A DIY'er over at do-it-yourself.com where i answer some Q's ( strictly a condition of my parole) actually read the instructions and asked about this!

this is redemming in that consumer advocates may eventualy catch on and send these cheapo fixtures back to tiawan
(just in time for China to invade!)

Sparky,

Have you seen fixtures without this warning?
I haven't seen any for a long time. I thought all fixtures had this warning now.

Bill

Bill,

Great point about surface mounted fixtures! That one slips my mind very often [but that's not hard for me!! - must be due to my post pubescent male menopause ].
Man, take down a surface mounted Incandescent fixture that has been driving a few 100 watt A19 lamps for years and the paint on the ceiling is Toast!! A regular Barbeque! Drywall Flambe`!! Plaster Thermador! [you get the idea ].

Steve,
Did you expect this thread to run out 30 replies?? Once again, congrads on a great discussion topic!

So, what's that DIY forum like? Are there many well informed members? Do many threads require Asbestos Keyboards / Monitors?? [thermo-nuclear wars]

Scott SET.

the warnings seem to be standard fare, i even noticed some cieling fans with warning that are displaced from the cieling.

Scott, credit must go to Bill , who gave me the idea here, it is a problem!!~!

the DIY'er forum has knowledgeable moderators and pinch-hitters for all trades and concerns, mostly repetitive explanations of where the white wire goes on the receptacle. some flamers over myserious sight-unseen diagnosis. good practice for refining the contractor-customer repore'...

.i am installing dimmable compact fluorescent recessed cans (26w) in my ceiling. the top of the fixture ( in the attic ) would only be 2.5 - 3 inches from the roof decking above. is that allowable ? NEC 410-66a sez 12" from combustables . can i flash the wood just above the fixture for heat dispersion/dissipation ? other insulators ? none of the above ?

thanks,
scott

scott57;
you need to use an IC can, then you may bury it in the insulation and 'in contact with combustibles'.

get some good IC's, usually these are viewed as an enclosure within an enclosure.

one can always tell a roof with non-IC cans in the winter around here.

scott57,

Welcome!
410-66a says 12.7mm (1/2 in.) from combustables. So it sounds like you're OK. If the cans are non-IC you have to keep the insulation 3 in. away from all parts of the fixture.


Bill

thanks for the replies. 12mm ? thats better, i thought it was 12" . i already have the fixtures and they are non-IC, and expensive, so i am going to use them ( without being dangerous ). so it sounds like if i keep the insulation >3" from the can and keep the can > 1/2" from combustibles i'm all right.

thanks,
scott

Scott57
non-IC's can be safely installed but
this may not be the best think for your roof

not the best thing for my roof ? meaning danger of fire ? no one has answered about flashing/fire barrier. i'm not holding anyone liable, just want to know what you all think.

scott

ps i live in san diego where there's never much on your roof to tell ic or non-ic. but also means nice dry tinder.

I wouldn't venture attempting to fashion some sort of heat shield. You never know the physical characteristics of homemades in actual practice. I've seen too many DIY fixes that obviously looked O.K. to someone (the installer), but made me wince. If you maintain proper clearnces, this should suffice. Otherwise try something else.(My opinion).

[This message has been edited by Redsy (edited 06-08-2001).]

it seems, on reading back through the thread, that i am in the right place. i am running all 90 C NM cable through my attic. it is a home run straight to the box. the fixtures are non ic with electronic dimmable ballasts rated at .25 amp (26w). fixture sez : maximum 8 12awg branch wires. i am daisy chaining them so the jb has 14/2 in and out ( to next fixture ) plus the 18 gauge they wired the ballast to the fixture ( 3 wires in to ballast, 4 wires out to socket ).more info for the thread.

scott

ps i got the fixtures after lots of painful back and forth at my local electrical supply house ( not home depot ). these new electronic dimmable ballasts aren't something everyone knows about. the trouble was matching the dimmer to the ballasts. conflicting opinions as to what would control which ballasts, etc. i've just hooked one up so far for a test. it dimmed beautifully and no noise or flicker. but the temperature thing i'm still pondering.

scott57;
the insulative barrier where i am up here in VT is something that should not be broken, so i suppose it's a different ball game where you are.
If you are using new 90 deg NM, then the temp rating thing is not a concern to your installation.
It is good , however, to hear a DYI'er pay close attention to detail.
The brunt of this thread deals with fixtures small diclaimers of wiring 1985 or before being suspect of lower temp ratings, thus an illeagal installation.
As the ratio of lighting fixtures manufactured VS remodels of post 85' homes has never been established we feel this is a problem.