Desk lamps power limitation (floor, Lowes, heat, insulating)

[snowmountains]

Perhaps all the desk lamps I have had had a caution warning to the effect that, to avoid fire, please use only max 25 (or 40) watt. I can understand it if it has a vulnerable shade material, but even with metal shade it has such warning. What makes it more dangerous with, say, 60w or 75w than a ceiling light?

[harry chickpea]

These are now being made cheap. 18 gauge zip cord used to be the standard, the cords on these have considerably thinner conductors. Sockets and switches are similarly being made of less massive material.

[Ohiogirl81]

Originally Posted by ssww

What makes it more dangerous with, say, 60w or 75w than a ceiling light?

Because the fixture isn't wired to handle increased wattage?

But go right ahead and test it out if you like. Have a fire extinguisher and the 911 operator handy.

[Pruzhany]

Originally Posted by ssww

Perhaps all the desk lamps I have had had a caution warning to the effect that, to avoid fire, please use only max 25 (or 40) watt. I can understand it if it has a vulnerable shade material, but even with metal shade it has such warning. What makes it more dangerous with, say, 60w or 75w than a ceiling light?

Keep in mind that these numbers are for incandescent light bulbs and not CFLs or LEDs.

[snowmountains]

Originally Posted by harry chickpea

18 gauge zip cord used to be the standard, the cords on these have considerably thinner conductors. Sockets and switches are similarly being made of less massive material.

Originally Posted by Ohiogirl81

Because the fixture isn't wired to handle increased wattage?

Ok I see.

Originally Posted by Pruzhany

Keep in mind that these numbers are for incandescent light bulbs and not CFLs or LEDs.

Yes I am aware of that. For CFL max is like 13w.

[MidValleyDad]

Originally Posted by ssww

Ok I see.



Yes I am aware of that. For CFL max is like 13w.

Is it? I have had a hard time getting a direct answer if a fixture labeled for a 60 watt bulb is limited to a CFL that puts out the EQUIVILANT of 60 watt or if it means an actual power usage of 60 watt (Which would allow a larger CFL bulb) And I have not seen a fixture labeled for a max of a 13w CFL (But I am mainly dealing with fixtures that came out before CFLs)

[chet everett]

Try and track down one of those multi-hundred watt halogen portable lamps? Know why they are all gone? Curtains, linens, pile of clothes too close and WHOOOSH -- FIRE! CPSC and Industry Announce Corrective Action to Improve Safety of Halogen Torchiere Floor Lamps | CPSC.gov

Why are there are still 100w+ chandliers? Not much chance of something being close enough to burn...

[RayinAK]

Originally Posted by ssww

Perhaps all the desk lamps I have had had a caution warning to the effect that, to avoid fire, please use only max 25 (or 40) watt. I can understand it if it has a vulnerable shade material, but even with metal shade it has such warning. What makes it more dangerous with, say, 60w or 75w than a ceiling light?

Ceiling lights usually have a layer of insulating material on the top surface between the ceiling and the light assembly. Most times the insulating material is made of fiberglass. Also, ceiling lights usually have a warning notice relating to the maximum light wattage.

Incandescent or halogen light bulbs produce a lot of heat, and the higher the wattage the more heat they produce. Halogen lights are notorious for producing high heat, and incandescent are next. Anyway, just keep in mind that regardless of light bulb or tube used, the lowest the wattage the lower the heat dissipated.

Just choose light bulbs, or tubes, or spiral (whatever) that produce the amount of light you want, but that are of the lowest wattage possible. LED lights seem to produce less heat than CFLs of the same wattage, and in general CFLs and LED lights produce the same light output of incandescent and halogen lights, but use little power. That's why they run cooler.

Summary: high watt = high heat. Low watt = low heat

[rational1]

Two issues here- (1) current-carrying capacity of the conductors and (2) heat.

Both are reduced for any resonable CFL bulb compared to incandescent.

I would not hesitate to use a CFL rated less than the maximum power draw (not equivalent light output!). Provided, of course, that it fits well mechanically.