Brian Posted September 11, 2011 Share Posted September 11, 2011 I've just been sent this. Given how often we talk about LED lamps for replacing filament lamps in 'domestic' settings it makes an interesting read. LED teardown.pdf Link to comment Share on other sites More sharing options...
dbuckley Posted September 11, 2011 Share Posted September 11, 2011 It notes in the article that "For all the claims of CFL longevity, I have yet to see them reach their expected lifetime" I had a CFL fail a couple of days ago, in the hallway, a pair of CFLs that burn long hours, this one being installed 21/12/05. The lamp is rated at 15,000 hours, and I reckon a got conservatively 17,000 from it, and maybe a goodly bit more. Having had an almost-all-CFL house for some years, there are definitely differences in quality, and so far, the Ecobulb (Kiwi web site, also available in Oz, UK and USA) is the hands down winner, with Phillips (in particular, their Tornado) being a distant second. Link to comment Share on other sites More sharing options...
musht Posted September 12, 2011 Share Posted September 12, 2011 I had a CFL fail a couple of days ago, in the hallway, a pair of CFLs that burn long hours, this one being installed 21/12/05. The lamp is rated at 15,000 hours, and I reckon a got conservatively 17,000 from it, and maybe a goodly bit more. Lumen maintaintenace is the figure missing, how much light is a CFL producing after 15K hours if the ballast hasn`t gone pfft at about 1.5K hours ;-) Its also missing from the report, 50-60 l/W what should be able to get, good halogen is getting near 40 l/W, but thats initial brightness whats it like after 500 and 5000 hours, 50K hours is usually projected 70% figure under ideal conditions and depreciation ain`t a straight line. Again the weak point does look like the cramtronics going on in the base... Link to comment Share on other sites More sharing options...
dbuckley Posted September 12, 2011 Share Posted September 12, 2011 Again the weak point does look like the cramtronics going on in the base... Cramtronics - like that! Yeah, this winds me up too; the very first CFLs had a separate replaceable lamp and a base, albeit the base was nothing more than a mag ballast back then, and the CFL had an integrated starter. Ok, there are still examples (PL4s and 2Ds) that don't have the onboard electronics, but its not a popular approach compared to the el cheapo all in one lamps. As to how bright the CFL was at failure after 17K on the clock? Sufficiently. Can't be more scientific than that, I'm afraid. E2A: And from the wicked irony department; the aforementioned failed CFL; it was in a horrible fitting, so a decision was taken to replace fitting as well as lamp. Job completed, apply power, and brand new (GE) CFL flickered and died!!!! Link to comment Share on other sites More sharing options...
timsabre Posted September 12, 2011 Share Posted September 12, 2011 CFLs fare best when on all the time (or not turned on and off very much).Standard domestic use when they are on and off all the time, they don't like it much. I suspect LED will be the same, a lot of the LED drivers give out a pulse of current when turned on which will not be good for the LEDs. Link to comment Share on other sites More sharing options...
Jivemaster Posted September 12, 2011 Share Posted September 12, 2011 While these are made as "prototype" size batches on a world market scale, they may have fair performance, once production gets outsourced to the cheapest bidder in the world will they ever achieve their life or lumen maintenance figures of the current examples. I remember a rumpus a while ago, 2D lamp replacements were retailing at £4 each and there were some copies at £2 BUT the copies were not the same as the prime manufactured ones and were poor value in terms of light output and quality and lamplife. Link to comment Share on other sites More sharing options...
boatman Posted September 23, 2011 Share Posted September 23, 2011 Here's a fairly recent announcement from Osram which may be of interest: http://www.osram.com/osram_com/News/Trade_Press/LED_OptoSemiconductor/2011/110916_LED_Spot.html Link to comment Share on other sites More sharing options...
musht Posted September 23, 2011 Share Posted September 23, 2011 Here's a fairly recent announcement from Osram which may be of interest: http://www.osram.com/osram_com/News/Trade_Press/LED_OptoSemiconductor/2011/110916_LED_Spot.html 60W 4075 Lumens, about 67 lumens a watt, pretty good, the candela game is slightly insincere though. Sample 60W MH lamps http://www.venturelighting.com/lampshtmldocuments/Uni-Form_60W_lamps.html 62892 MHL 60W 4800lumens 40,000Hrs lamp life 38822 MHC 60W 6900lumens 20,000Hrs lamp life Ceramic Metal halide need a CRI of 90+ 95060 MP 60W 4100lumens 20000hrs So LED is getting better but so are other sources. Link to comment Share on other sites More sharing options...
bigclive Posted September 23, 2011 Share Posted September 23, 2011 Having had an almost-all-CFL house for some years, there are definitely differences in quality, and so far, the Ecobulb (Kiwi web site, also available in Oz, UK and USA) is the hands down winner, with Phillips (in particular, their Tornado) being a distant second. Here in the UK a prominent CFL lamp is the Philips Geni, which is also one of the least reliable with the shortest life of any of the CFLs I've used. I think it's just the cheapest Chinese tat they could get, rebadged and used to cash in on the "funding" available to artificially make CFLs "affordable" at the tax payers expense. On the other hand, some of the generic cheapo brands have actually been quite good. Either way you have to keep in mind that the intensity fall-off over the life of a CFL is considerable, so it's worth changing them before they fail. Otherwise you are using just as much electricity for half the intensity or less. Link to comment Share on other sites More sharing options...
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