Lamp+CFL=melting CFL,blackened socket!

[zeddy]

We have a lamp (student desk type lamp) that is on in our basement 12 hrs a night. We had a CFL lightbulb in it because it is on so long each night. Last night it burnt out so hubby went to change it tonight. The light bulb had started to melt at the base of curly part. The lamp, which is thankfully metal, is all black on the inside near the light socket. It certainly looks like it could have started a fire. Do we contact someone? The lamp was cheap and is old and I have no idea of the brand of light bulb. I am even less of a fan of CFLs after seeing this!

[CaptSmethwick]

There were a couple of recalls years ago of defective CFL bulbs posing a fire hazard. If your bulb was purchased around 2002 or 2003, it may have been one of those. Those bulbs were 13w units sold under the "Globe" brand. If yours was one of those, consider yourself fortunate. Also, there are other recall notices from time to time - you can educate yourself on these at the underwriters laboratories website. While you're there, you could send them an e-mail asking if they're interested in your "case".

[GeneralDisaray]

simple, do not use high wattage cfl's in small enclosures that are not well ventilated. it could be a defective cfl or just burnout from the heat buildup.

most likely the socket was plastic and that WILL cause a fire being on for 12 hours a day. you need to use lamps that have ceramic socket bases.

[mrcantrell]

We have a lamp (student desk type lamp) that is on in our basement 12 hrs a night. We had a CFL lightbulb in it because it is on so long each night. Last night it burnt out so hubby went to change it tonight. The light bulb had started to melt at the base of curly part. The lamp, which is thankfully metal, is all black on the inside near the light socket. It certainly looks like it could have started a fire. Do we contact someone? The lamp was cheap and is old and I have no idea of the brand of light bulb. I am even less of a fan of CFLs after seeing this!

What wattage is the fixture rated for? CFLs generate about 1/4 of the heat that an incandecent or halogen bulb do. As mentioned I can almost guarentee that this was a cheap/junky bulb. When CFLs overheat the ballast turns yellow, not black.

It's also possible that there was a crack in the tube that caused the issue.

[mrcantrell]

most likely the socket was plastic and that WILL cause a fire being on for 12 hours a day. you need to use lamps that have ceramic socket bases.

I don't agree. If a fixture is rated for a 60 watt incandescent light bulb it should have no issue running a 13 watt CFL for any length of time.

Remember, a watt is not a measure of light output (that's a lumen) it's a measure of heat. Therefore any bulb rated at 60 watts, regardless of the technology (ie halogen, led, incandescent, CF) is going to generate the same amount of heat. If a socket or fixture is rated for 60 watts then 1/4 of the heat shouldn't be an issue.

[coolspot]

simple, do not use high wattage cfl's in small enclosures that are not well ventilated. it could be a defective cfl or just burnout from the heat buildup.

most likely the socket was plastic and that WILL cause a fire being on for 12 hours a day. you need to use lamps that have ceramic socket bases.

A 13W CFL generates a lot less heat than a 60W bulb.

Lights are rated for wattage not light output.

[Pete_Coach]

CFL failures is not an unusual problem. It is happening quite often, regardless of brand or price point. We are hearing more about it simply because there are so many more being used.
Here is a notice and forum with some photos
http://esainspection.net/pdf/Safety_Alerts/07-03-AL.pdf
http://bbs.homeshopmachinist.net/showthread.php?t=27197
The thing is that the actual light itself is not failing but the circuitry within the light. The wattage is also not relavent because it is is happening in all wattage ranges.

[tdott]

Remember, a watt is not a measure of light output (that's a lumen) it's a measure of heat.

No, It measures rate of energy consumption/conversion.

Heat is a result of the consumption/conversion, but does not related directly to it. ie all 60w devices do not produce the same amount of heat, rather they use the same amount of energy.

[t3359]

I don't agree. If a fixture is rated for a 60 watt incandescent light bulb it should have no issue running a 13 watt CFL for any length of time.

+1 A typical fixture would not be limited to the current it can supply but rather the heat it has to deal with.


Remember, a watt is not a measure of light output (that's a lumen) it's a measure of heat. Therefore any bulb rated at 60 watts, regardless of the technology (ie halogen, led, incandescent, CF) is going to generate the same amount of heat. If a socket or fixture is rated for 60 watts then 1/4 of the heat shouldn't be an issue.


No, It measures rate of energy consumption/conversion.

Heat is a result of the consumption/conversion, but does not related directly to it. ie all 60w devices do not produce the same amount of heat, rather they use the same amount of energy.

tdott is correct on this one. For a given wattage, the efficiency is the amount converted into light. The remainder would be lost mostly as heat.

bjl

[zeddy]

CFL failures is not an unusual problem. It is happening quite often, regardless of brand or price point. We are hearing more about it simply because there are so many more being used.
Here is a notice and forum with some photos
http://esainspection.net/pdf/Safety_Alerts/07-03-AL.pdf
http://bbs.homeshopmachinist.net/showthread.php?t=27197
The thing is that the actual light itself is not failing but the circuitry within the light. The wattage is also not relavent because it is is happening in all wattage ranges.

Thank you! The links were very informative.