Re: Dissecting CFLs

["Robert Green" <ROBERT_GREEN1963@xxxxxxxxx>]

"Andrew Gabriel" <andrew@xxxxxxxxxxxxxxxxxxxx> wrote in message

<stuff snipped>

> Nothing that fancy -- just a screwdriver, knife, and pliers.
> Some come apart along the seams, others are solvent welded.

Tried that, was afraid I might break the bulb.  It turned out to be rather
easy to freehand a cutoff wheel around the slot at the top of the plastic
"components bay."  A few side cuts and it popped out, although I did break
or cut one of the wires to the tube.

I was surprised to see no apparent component damage.  There's a nick in the
transformer insulation, but I think it was my doing with the Dremel.  The
can-type capacitor had a slight bulge on top, but nothing like what I've
seen in dead ones.  While this is not the old lamp from the Taiwanese
formula theft era, the capacitor looked like those that I have seen on
failed motherboards.  I'll bet those bad capacitors got around more than
anyone realizes.  It's only PC builders that regularly inspect boards
closeup that might have even noticed it enough to raise the alarm on the
web.  I really expected to see a fried component.  There's a strong smell of
overheated plastic inside, but these things run hot normally.

> I bought several of those large Ikea lamps at the time. One
> had an early electronics failure. The case quite easily unclips
> so I saved the almost new tube and chucked the rest. Of the
> remaining ones, some ~7 years later, the second one just died
> of old age (worn out tube electrodes). I uncliped and chucked
> the tube, and refitted the tube saved from the early electronics
> failure, and it works again. Don't know if I'll get another 7
> years from it -- the electronics might not last that long as it
> runs quite hot in an enclosed fitting.

I think this tube is still good.  It flickers when I hit it with a static
shock.

> >> At the time I wrote that article, low power electronic control
> >> gear was somewhere between expensive and unavailable. Now that
> >> it's more readily available, I wouldn't actually suggest reusing
> >> it from dead lamps, although the downlighters covered at the
> >> end of that article are all still running from the original
> >> 8 year old control gear from some Philips PL Electronic CFLs.
> >
> > This is just an R&D exercise.  (Rip open and Destroy, in the best
Brainiac
> > tradition. (-:  )
> >
> > From what you've written, I'm expecting to see a dead capacitor in the
GE.
>
> It could be just about any component.
> Resistors are good at smoke too. Semiconductors
> usually just go pop and crack the case if you
> look carefully. Some electronic control gear
> deliberately burns itself out when the tube
> dies so it doesn't keep trying to restart it,
> although that normally happens without any
> smoke.

I suppose I could snip and test components one by one, but this was a cheap
bulb.  I just had ANOTHER Lights of America triaxial fail with only a dim
glow in the central tube.  It would be nice if I could recover some
functionality from these things, even if I have to hardwire them into a
lamp.

Do you have any thoughts on whether the trickle current from an X-10
appliance module could cause premature failures in CFLs?  I've been
experiencing an ever-increasing failure rate.  I suppose I need to run side
by side test of a bulb switched on and off by mechanical timer v. a X-10
timed bulb, but I've already got way too many science project on the list!

--
Bobby G.