CFL Ballast Fire

yuandrew

Flashlight Enthusiast
Joined
Apr 12, 2003
Messages
1,323
Location
Chino Hills, CA
This just happened to a friend of mine on the Air Raid Sirens forum a few days ago. He lives on a ranch and was checking on some things in the barn after dark when he noticed that there was no light at one end of the building. When he went to check the bulb, he found this and a blackened fixture.

BurntBulb3.jpg
 

65535

Flashlight Enthusiast
Joined
Dec 13, 2006
Messages
3,320
Location
*Out There* (Irvine, CA)
Probably and old cheap magnetic ballast that shorted out due to old age, luckily now days failure is quite uncommon (at least failure that results in damage).
 

Illum

Flashaholic
Joined
Apr 29, 2006
Messages
13,053
Location
Central Florida, USA
something tells me the flickering/zapping tube I have beside my bed needs to be replaced:ohgeez:
Should it decide to burn, the assembly will fall squarely onto my lithium stash :eek:
 

SafetyBob

Enlightened
Joined
Oct 20, 2007
Messages
766
Location
Yukon, Oklahoma
Just for the record, every CFL I have purchased over the past 6 to 8 years and that has failed....around 5 or so, have failed similar to this one, but not as bad.

The last one in a bedroom had me in a panic because there was a definate smell of burning electrical in the air. As yours fail, you will notice that at the bottom on at least one tube, the plastic will be melted and you should also see discoloration. This has happened with most of the brands that I have purchased (inside the house and outside). That includes Sylvania, the store no-name brand from Home Depot, and GE brands all made in China. All of the failed units to repeat were over 3 years old with most being 4 years or older.

TCP brand from 1000bulbs that are now also 4 years old or older have not failed nor have the Microbrite brand which are 3 years old.

Bob E.
 

PhotonWrangler

Flashaholic
Joined
Oct 19, 2003
Messages
14,367
Location
In a handbasket
My experience with CFLs has been similar; they've all failed because of the ballast, although not as dramatically as the one in yuandrew's friend's barn. We throw away a lot of perfectly good mercury-filled glass in the name of being "green." :shakehead
 

Zelandeth

Flashlight Enthusiast
Joined
Nov 28, 2002
Messages
1,194
Location
Northeast Scotland (Aberdeenshire)
Looks to me like a ballast failure there.

Magnetic ballasts tended (at least in the UK where they're simple due to our 230V mains - in the US, you'd need autotransformers to step the voltage up...so they're probably more complex and I imagine somewhat more temperamental), to be very reliable. The only failure mode was occasionally through overheating, which tended to lead to them going open circuit in a somewhat smelly but otherwise utterly undramatic manner.

Two problem failure modes in modern electronic CFL's.

Firstly being the ballast, which runs so hot (especially when run base up and/or in enclosed fixtures) that it usually ends up cooking one or more cheap electrolytic capacitors which aren't designed to take the heat - what happens then is hard to predict, varying from a dead lamp, to a flickering lamp, to a loud bang and potential flames. Decent lamps should have a casing made of flame retardant plastic that won't burn. I've TRIED to set fire to the casing of a decent Osram CFL with a blowtorch without success. A cheapo from Tesco (which I belive to be made by GE - don't quote me on that though as it's only a theory) however did burn, though it took a fair amount of starting. This tends to be a problem either in poorly designed higher power lamps, or very compact ones where no thought has been given to ballast cooling whatsoever. It's hard to get a sense of scale from that picture, but that looks like a 20W or so lamp there from the diameter of the spiral.

The second problematic failure mode is again down to the ballast. Even when an electrode has lost its emissive coating, a lot of modern electronic ballasts have the ability to provide sufficient voltage to still maintain a discharge. However the resulting higher voltage drop at the electrode in question means that there's a ridiculous amount of power being dissipated there compared to what it was designed to deal with. The vast majority of the time this will blow the filament open circuit, shutting down the lamp in pretty short order. Sometimes however that doesn't happen, resulting in tube end temperatures sufficiently high to soften or crack the glass. Or, theoretically melt the plastic around the base, though I've never seen it actually set fire to a lamp. It can however coax a ballast (which will be pretty well aged by that point) into failing, as it will be running at a higher tube voltage than it was designed for - the imbalance in electode voltage drops will also lead to a certain amount of rectification taking place, again - not good for the ballast.

A decent ballast should be designed in such a way as to "see" electronically when the emissive coating on an electrode has been exhausted, and shut the lamp down, especially given the trend for ever narrower tube diameters these days.

It's still scary to see things like this happening though! If that had been in a house, left on unattended and it fell onto a sofa or was next to a set of curtains, or even onto someone - the results just don't bear thinking about.

I'd be getting in touch with the manufactuer of the lamp if I were you. Certain environments don't mix well with CFLs either, if the barn in question is at all damp, that could well play a part, electronics and water don't generally play well together, for that reason the lamp in my parents shed is still an incan - I got fed up of CFLs fizzling out in the winter due to condensation.
 

jufam44

Enlightened
Joined
Sep 29, 2007
Messages
291
Location
CA
It's happened to me before, we had a light blow up in use in a theater, and it burned happily for about a minute until the nice fire extinguisher put it to rest. Boy, what a pain to clean up after. Ours were running on 120v 60hz and the ballasts were all modern (I.E. 2007). Granted, these were not CFL's in the common sense, as ours were 8 compact flourescents minus ballasts in the base, and one big ballast on the top. I'll post a pic once my website starts working again.

-Max
 

jrmcferren

Enlightened
Joined
Aug 20, 2006
Messages
403
Location
Waynesboro, Pa FM19es
Update:

Well, I found out the bulb he had which caught fire turned out to be a Lights of America.

The only name brand CFL I have had fail on me was a lights of America lamp. It was an A-Shaped lamp and it started flickering. At that point I determined the lamp unusable and I got a GE spiral. I was in dorm at the time and I'm glad it did not fail in the manner of the lamp above.
 

WildChild

Flashlight Enthusiast
Joined
Apr 26, 2005
Messages
1,424
Location
Québec, Canada
Here in Canada, I've had three 9W and one 13W CFLs from Globe Electric fail suddenly within 2 years of use (and less then 2000h). I'm starting to believe they are not the solution at all with this high failure rate... It will cost more to replace them prematurately than the price of the electricity + incan bulb...
 

SafetyBob

Enlightened
Joined
Oct 20, 2007
Messages
766
Location
Yukon, Oklahoma
It is truly unfortunate that there appears to be no manufacturer that can make a descent, quality CFL for a reasonably low price.

Our only solution it to keep a very close eye on the ones we own. Sooner or later, they will get very hot and give up, hopefully a fire will not ensue.

Bob E.
 

paulr

Flashaholic
Joined
Mar 29, 2003
Messages
10,832
I've had several CFL's fail and found what looked like scorch marks on them post-failure. This has been worrisome. They were the cheap bulbs subsidized by my local electric utility but they appeared to be of reasonable quality, not the REALLY awful kind found in dollar stores. I then bought an expensive CFL ($12 or something) at the hardware store which the store guy said really does last a long time. That one went away when my landlord came in and replaced all the screwbase light fixtures in my building with fluorescent fixtures, so I never got to see how long it lasted. The landlord-installed fluorescents are still running ok after I think a year or so. I haven't opened up the fixture to see what kind of bulb base is used. I can see through the fixture that they are U-shaped tubes about 6 inches long.
 

Yoda4561

Flashlight Enthusiast
Joined
Jan 22, 2007
Messages
1,265
Location
Florida, U.S.A.
Well geez now ya'll got me worried. We have all CFL replacement bulbs in our house now, about 15 of them in total. and some of them are in enclosed fixtures. Now I did make sure to only use bulbs that said they were okay for use in those fixtures but stuff will inevitably fail. I figured they would just fail in the off state with an electronic ballast, not burst into a burning and charred lump of glass and plastic.
 

JohnR66

Flashlight Enthusiast
Joined
Aug 1, 2007
Messages
1,052
Location
SW Ohio
Wow! Never seen one burn up like that. I've been using CFL's since 1991 and now have 20 some fixtures using them. The older tri U tube sylvanias I had from the mid 90s would give off an odor when they died. Autopsy revealed melted capacitors in the output (connected to the tube leads) part of the circuit.


All the newer ones that have gone out just stop working. No outwardly visible damage. Lifetime in all but a couple cases has been satisfactory.


If catastrophic failure has been an issue, you'd bet there would be recalls and reports on the evening news. The media has already attempted to bash CFLs for their mercury content even though the older linear tubes have much more raw Hg in them. CFLs have Hg stored in an amalgam that should reduce exposure if the lamp is broken.
 

lpcmidst128

Newly Enlightened
Joined
Jan 27, 2006
Messages
37
Location
San Francisco, CA
Update:

Well, I found out the bulb he had which caught fire turned out to be a Lights of America.

I had 2 Lights of America cfl that failed on me. One of them made this loud pop sound and a bit of smoke came out, good thing no fire. The other bulb just quit working after a month.
 

TPA

Enlightened
Joined
Aug 26, 2005
Messages
342
Location
Florida
The only catastrophic CFL failures I've had were Lights of America bulbs. Very shoddy parts inside them. I did have a GE dimmable fluorescent torch lamp (that I loved) shoot its ballast one night, but it was less dramatic. Just a slight transistor burning smell then it went dark permanently.

All of my other modern (electronic ballast) CFL failures have just been your typical fluorescent fail-to-arc where the bulb just doesn't come on. Not sure if this is an improvement over the old magnetic ballast fixtures where the bulb would eternally re-strike and flash over & over while the mag ballast would get up to high temperatures. Flashing bulbs tended to get replaced quickly.
 

reptiles

Enlightened
Joined
Nov 26, 2001
Messages
363
Location
Philadelphia PA
I bought a few Phillips candelabra CF units. Although they didn't actually burn like the example in this thread; one did emit the "burning electronics" smell and promptly died.

I actually followed up and sent it back to Phillips for a replacement (which they provided) but they also said it died because I must have dimming switches, three way switches, or illuminated neon switches in my house.

While I do admit to having a few neon switches, I think it was an incompatibility with an X10 switch. I don't use dimable "lamp" modules but do use on/off appliance modules on my CF lamps. Maybe they are wacky with that combo??

I should have saved all the old wall switches I upgraded years ago.

Regards,

Mark
 

jrmcferren

Enlightened
Joined
Aug 20, 2006
Messages
403
Location
Waynesboro, Pa FM19es
I bought a few Phillips candelabra CF units. Although they didn't actually burn like the example in this thread; one did emit the "burning electronics" smell and promptly died.

I actually followed up and sent it back to Phillips for a replacement (which they provided) but they also said it died because I must have dimming switches, three way switches, or illuminated neon switches in my house.

While I do admit to having a few neon switches, I think it was an incompatibility with an X10 switch. I don't use dimable "lamp" modules but do use on/off appliance modules on my CF lamps. Maybe they are wacky with that combo??

I should have saved all the old wall switches I upgraded years ago.

Regards,

Mark
Hmm, using appliance switches should not be a problem. I believe these switches use a relay to switch the load on and off, not a triac as a regular lamp module uses.
 
Top