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I know that this question may be off-topic here, but I'll ask it anyway since they do have electronics inside.

I've noticed that my fluorescent lamps keep dying after only couple of months of use. When they die, they die in groups of 2-3 and as far as I can see, both new and old lamps may die during such events. As far as I can see, electronics inside dead lamps look normal to me, but then again, I don't have much experience in electronics, so I could be wrong.

So I'm asking you people what could be the cause and how can I prevent it? I'm thinking about bad electricity supply, because I have frequent brown-outs, but as far as I can see, deaths of lamps aren't more frequent during times when I have brown-outs. I'm thinking about connecting lamps over a UPS or "power conditioner".

UPDATE:
I did some investigating and I think that I've found source for my problem. As I mentioned, I had brownouts. I noticed that nobody in my area had brownouts, so I the problem was probably with my installation. Then I noticed that voltage for two phases was between 220 V and 230 V, as expected, but one was between 190 V and 200 V. The main cause for that seems to be a 35 A DIAZED DIII fuse which is connected to the phase which powers my lamps. It turned out that the tip of the cartridge and fitting element of the fuse case were corroded and were sparking and overheating (the cartridge was so hot that I had difficulties removing it). It also turned out that when power company replaced my electromechanical meter with solid state meter, they installed new circuit breakers in such way that fuses are serially connected to breakers and are "downstream" from them. I talked to few electrical engineers and electricians and they all believe that since circuit breakers are installed, fuses should be removed. I'll get an electrician to remove them will report back how that effected lifetime of my lamps.

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  • \$\begingroup\$ Brownout (or, conversely, surges) could be possibilities, but you'd need to take some measurements before an EE can really make any comments. Do you have a logging DMM? \$\endgroup\$ – Kevin Vermeer Oct 27 '10 at 17:51
  • \$\begingroup\$ @reemrevnivek Unfortunately, no. I did actaully do some measurements during brownouts, but effective voltage is around 220V according to my DMM, which is what it is supposed to be in my country. I know It's a brown-out mainly because my UPS keeps switching to its internal power source and effects this makes on lights. \$\endgroup\$ – AndrejaKo Oct 27 '10 at 17:58
  • \$\begingroup\$ @reemrevnivek It could be that my DMM doesn't update screen fast enough to get a relevant reading too. \$\endgroup\$ – AndrejaKo Oct 27 '10 at 18:05
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Schematics & Photos for 17 CFLs

Failures

Common failure is broken capacitor C3. it is possible mainly at cheap lamps, where are used cheaper components for lower voltage. Whet the pipe doesn't lights up on time, there are risk of destroying transistors Q1 and Q2 and next resistors R1, R2, R3 and R5. When lamp starts, changer is very overloaded and transistors usually doesn't survive longer temperature overloading. When the pipe serve out, electronics is usually destroyed too. When the pipe is old, there can be overburned one of filaments and lamp doesn't lights up anymore. Electronics usually survives. Sometimes can be pipe broken due to internal tension and temperature difference. Most frequently lamp fails, when power on.

Reviewing

Most of these compact fluorescent lamps use same or very similar wiring. More expensive lamps use a little complicated wiring with electrode preheating and thanks to it they have longer lifetime.

LUXAR 11W

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As you said, it's going to be tricky to figure out the cause of why these bulbs die - but it could be affecting other appliances too. Have you noticed any other devices malfunctioning or breaking?

Most CFL's and the ballasts are designed to be cheaply produced; the ballast is based off a simple self-resonant circuit and thus has little protection against problems on the line.

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  • \$\begingroup\$ Well it could be. A TV's power supply died suddenly and my air conditioning device keeps acting strangely. One time several power supplies with voltage auto-detection died, but I think that main reason for that is the fact that power company's technicians working at my power meter at that moment connected two phases together instead of a phase and zero. \$\endgroup\$ – AndrejaKo Oct 27 '10 at 18:03
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    \$\begingroup\$ I'd have it checked out by an electrician (in fact, as it's the power companies' equipment that usually affects the voltage the power co. may do it for free.) \$\endgroup\$ – Thomas O Oct 27 '10 at 18:17
  • \$\begingroup\$ When you say the A/C acts strangely, what do you mean? \$\endgroup\$ – Thomas O Oct 27 '10 at 18:17
  • \$\begingroup\$ I wish I could give you more than one up-vote for mentioning electrician. \$\endgroup\$ – AndrejaKo Nov 1 '10 at 11:27
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Off the top of my head: Vibration from ceiling fans, many on/off cycles, heat, bad power format, cheap CFL.

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  • \$\begingroup\$ I've been using CFLs in trouble lamps for a while - they're much more resistant to vibration than even heavy-duty incandescents. \$\endgroup\$ – Kevin Vermeer Oct 27 '10 at 19:45
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If your CFLs are in enclosed fixtures and are not specifically rated for such, I'd say that's the problem. Most are designed to be used in open fixtures with the base down so the heat can rise away from the electronics. To keep costs down, they have electronics designed on the hairy edge. The heat can easily dramatically shorten their life

I started recording lifespans and found that in an enclosed fixture, my CFLs had a typical life of one to three months. Used as designed, open, vertical and base down, they tend to not die.

I'd suggest either going back to incandescent in your closed fixtures or paying extra and purchasing CFLs specifically rated for enclosed fixtures.

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    \$\begingroup\$ Interesting answer! The problem here is that so far I haven't actually seen CFL on whose box was printed if it was rated to be used in enclosed fixture or not. \$\endgroup\$ – AndrejaKo Nov 2 '10 at 8:07
  • \$\begingroup\$ candlepowerforums mentions a few enclosed rated CFLs a b "rated for use in totally enclosed fixtures". \$\endgroup\$ – davidcary Jan 18 '12 at 13:12
  • \$\begingroup\$ another CFL c "for totally enclosed fixtures". \$\endgroup\$ – davidcary Jan 21 '12 at 12:49
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Funny you mention that your CFLs have a short life. In this month's Silicon Chip magazine, page 7, a reader wrote in with the same complaint. It turns out that Philips would not offer a warranty on their CFLs if used in an enclosed fixture. However no explanation to why was offered by Philips or discussed in the article. I would scan the page to show you the letter but I don't need Leo Simpson getting cranky with me.

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    \$\begingroup\$ That's very interesting. The lamps which are problematic are all in enclosed fixtures. \$\endgroup\$ – AndrejaKo Oct 28 '10 at 7:41
  • \$\begingroup\$ I thought I read the heat caused by the lamps in the enclosed area damaged the ballast, but I don't have any references to back it up. \$\endgroup\$ – pfyon Oct 28 '10 at 12:32
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    \$\begingroup\$ I've seen the same repeated early failures on lamps that are not enclosed, and have enclosed ones that do not suffer these early failures. At least in my case heat does not appear to be the root cause. Still searching. Could get real pricy continually blowing out expensive CFLs every month once we're forced to use only those (currently I just switched the offending locations back to incandescent which are lasting fine). \$\endgroup\$ – Brian Knoblauch Oct 28 '10 at 13:41
  • \$\begingroup\$ Might be time to start stocking up on incandescent lamps... \$\endgroup\$ – user1307 Oct 31 '10 at 0:04
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seems the new bulbs are made in bulk with cost saving strategy. Not a novelty any more. We will have to figure out what brands are lasting and what brands are blowing early. I have had 9 of these bulbs blow in 4 months. However, I have larger ones that have lasted over 6 years now. Seems the compact ones are the problem. I have them enclosed and open.

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  • \$\begingroup\$ Welcome to EE.SE. This doesn't really attempt to answer the question and would be better as a comment. Once you have earned 50 reputation you will be able to comment everywhere. \$\endgroup\$ – Null Nov 21 '14 at 1:33

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