diagnosing electronic light bulb on christmas

hi folks,

i have a PLED compact floresent (well not so compact its a 6" globe) bulb in my chandelier. resembles:

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all of a suddent it is not turning on any more.i put in an incandescent bulb in that holder & it lit immediately.i put the PLED back and it still didnt light.

what is strange is then when i slowly unscrew it, it will light for a split second. this is why i am still optimistic that the PLED still works. what could be wrong?

merry christmas

Reply to
s
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Its dead ! The slight current causes an arc as you break the contact causing the tube to flick on for a second.

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Best Regards:
                      Baron.
Reply to
Baron

Sort of. It's probably got a bad solder connection and the twisting is causing intermittent contact. Unless you're skilled at eelectronics soldering, it's not worth repairing. If you are and can get the base apart non-destructively, touch up the solder connections on the PCB. There will likely be one or more with obvious cracks.

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Reply to
Sam Goldwasser

i sort of 'scalped' the bulb base to get access and be able to unplug the pcb from the twin spiral florescent tubes hidden inside the frosted glass globe.

i touched up a few of the solder joints and re assembled without glueing it together yet ,but it didnt work. what i did notice was if i flick my fingernail against the glass globe it lights up and is then able to turn on in subsequent attempts.it appears that once warmed up it doesnt need any more flicking to turn on.

what is puzzling me is that if 1 tube has some sort of fault, why isnt the other turning on? i have included a small 80k photo of the circuit parts. at this stage this is more of an educational experiment rather than a repair - i doubt i will be able to get this bulb looking neat enough to complement my chandelier.

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thanks

Reply to
s

Move to Australia.

Down here they give the fluorescent bulbs away free of charge as an energy saving method. ;-)

Reply to
grumpy

I see this sort of thing fairly often. These cheap CFLs are not particularly well built and the electronic ballasts tend to get flaky due to cracked solder joints or bad capacitors and I've seen the symptom you describe. Usually you can split open the ballast housing to access the circuit board inside if you'd like to try to repair it.

Reply to
James Sweet

Get back in there and touch up some more joints, it sounds like you're on the right track.

Reply to
James Sweet

saving method. ;-)

But still might be worth trying to keep it out of a land fill! :)

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Reply to
Sam Goldwasser

James Sweet wrote in news:%cLjh.886$Ej7.774@trnddc02:

I too have had bad luck with "no-name" CFL bulbs. I found them to be a waste of time and money. Most of the time they don´t even give enough light. A supossedly 23W no-name CFL will probably give less light than a

15W GE CFL, for example.

It´s better to spend a little more money and get CFL´s from a better brand like GE, Phillips, Osram and so on. The best CFL´s I ever get where made by Osram, followed by the ones produced by GE. Phillips is hit and miss. They use good tubes, but sometimes their electronic ballasts suffer from early failure of the starting cap.

Reply to
Luis Martino

Probably one of the filaments is O/C

--
Best Regards:
                      Baron.
Reply to
Baron

i must have found what was loose as its consistently turning on now.i think the connector btwn the pcb & tube contacts was a bit loose.i glued the case all back together and am waiting for it to dry.

i am wondering a bit about the economy of such bulbs. even though i save on energy consumption using it, i wonder how much more energy is required (compared to incandescent light production) for such a sophisticated bulb, along with all the additional toxic processes necessary to make the electronic components.

are energy saving bulbs more a case of keeping our environment clean while increasing pollution in some remote country where the bulbs are made?

Reply to
s

Hey ! Glad you got fixed. They are so cheap I no longer bother trying to fix them. Plus as you have discovered, they are a pain to get into. Dry joints, blown triacs and O/c heaters seem to be the common problems. I once made a high frequency inverter that would strike a tube with O/c heaters. The tube over about two weeks just went dim and bluish.

As far as pollution is concerned, I tend to agree with you. I would imagine that an energy analysis of the energy to make the components over energy saved would be marginal or even negative.

Certainly the energy saved comparison with an equivalent incandescent light bulb is real enough !

PS Merry Xmas.

--
Best Regards:
                      Baron.
Reply to
Baron

re CFLs

Its not a case of comparing one bulb with one, but one bulb with 8 or

10 filament bulbs. The CFLs dont create any extra junk over 8 filaments.

Also the big difference is with electricity use, and this dwarfs any materials and embodied energy differences.

I wonder if there may have been a dc component flowing? If so, turning the bulb connections round may do it.

NT

Reply to
meow2222

re CFLs

Its not a case of comparing one bulb with one, but one bulb with 8 or

10 filament bulbs. The CFLs dont create any extra junk over 8 filaments.

Also the big difference is with electricity use, and this dwarfs any materials and embodied energy differences.

I wonder if there may have been a dc component flowing? If so, turning the bulb connections round may do it.

The other option is to bypass the electrodes completely, and feed it through metal strips on the tube glass.

NT

Reply to
meow2222

I doubt it it was fed from a transformer with a capacitor in series ! Probably I just shoved too much current through it. I was just playing about and didn't take too much time and effort in getting it right. Anyway at about 100KHz or so, the thing jammed every radio device in the house. Even the TV patterned when it was on.

The tube was shaped like a trio of "U"s. I doubt that I could have put metal strips on it. Although I once did that with a four foot tube in a display so I could feed it from the bottom. The tube actually came with a metal tape bonded onto it. It was connected to the metal caps on each end.

--
Best Regards:
                      Baron.
Reply to
Baron

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