Post by Peter Jason
I am decking out an old chandelier with 40W 12V halogens.
Is it true that handling these capsules shortens their lives? What
sort of glove (cotton/latex) should I wear to prevent this?
Finger grease which is left on them when they run up to operating
temperature will react with the quartz glass, leaving black marks
in the glass which can't be cleaned off. In higher power lamps
which operate at higher pressures, the black marks absorb heat
and soften the glass, and the high pressure causes it to balloon
out at that point. That's unlikely to happen in a 40W lamp though,
and if the capsule is intended to run without secondary containment,
it's probably not a high pressure capsule.
If you get finger grease on a capsule, wipe it off with alcohol
before you use the lamp (and make sure the alcohol is all evaporated!).
Latex or PVC gloves are probably best. Cotton or even a tissue will
work once or twice, but will eventually soak finger grease through.
Alternatively, you might be able to find a capsule holder, or even
just a piece of wide PVC sleeving to use to hold the capsules.
The ones I used came in a tiny plastic bag, and I left the bag on
until just after I had pushed them into the holders.
BTW, I similarly converted a chandelier some years ago. It had used
60W mains filament lamps, but was noticably brighter when converted
to use 12V 35W halogen capsules.
If you live in the EU, you should note that all these halogen lamps
are due to be banned in 2016. The EU lighting industry which originally
pushed for the ban is now back-tracking and trying to get the EU to
change its mind because it will kill their consumables business, but
the EU hasn't changed its mind yet, and the newer LED lighting
manufacturers are pushing the EU to retain the existing plans.
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