wrote in message
...
On Sat, 18 Aug 2012 15:01:48 -0400, Bill wrote:
Tomsic wrote:
"Bill" wrote in message
...
zzzzzzzzzz wrote:
On Fri, 17 Aug 2012 15:22:28 -0400, Bill wrote:
zzzzzzzzzz wrote:
On Fri, 17 Aug 2012 12:15:41 -0400, "Stormin Mormon"
wrote:
Thanks for the follow up report. I'm pleased it all worked out.
Ceiling fans are very rough on bulbs -- they may need "rough
service"
bulbs.
If the blades are properly balanced, they're not too hard on bulbs.
In
four
years, the only ceiling fan bulbs I've lost were the ones on the
back
porch,
in a fan that's never used. Three of the four went.
Forgot to mention, that the outside fan was one of six in the house
with
lights. None of the other lights has failed in that four years.
When I used 100W bulbs in my ceiling fan which has a globe, I was
going
through them practically monthly. When I switched to 60W, I got more
normal bulb-lifetimes.
What was the rating on the fixture?
The rating of the part that held the bulb was/is quite high (I don't
recall the number, but it is greater than 100W). However, it surely
did
not take the globe into account. Evidently, it was the heat in the
globe
that was giving the bulbs a short lifespan. I am sticking with the 60w
bulbs for reasons of safety. I inherited the lamp as a home-buyer, so
I
don't know what it said "on the box" of the fan.
Heat doesn't affect bulb life unless the basing cement on the bulb
fails or
the glass melts. Shock and vibration or higher than rated voltage
kills
bulbs prematurely though.
Well, it did in my case, so it must have effected the basing cement. Is
that possible? It wasn't the vibration, becasue this phenomenon
occurred even when I didn't turn the fan on (at all).
Tomsic
Heat affects the vibration resistance of a fillament. The hotter it
is, the more fragile.
Yes, assuming you mean the temperature of the filament. A few degrees of
fixture or bulb temperature even around 100 degrees Celsius does nothing to
an incandescent filament already operating at 2427 Celsius. In addition,
the tungsten filament is self-regulating as its resistance is a function of
its temperature.
Even if the fan is off, there may be vibration in the house that gets
transmitted through the fan structure to the bulbs. I had a trouble call
once where the complaint was that the bulbs in a dining room chandelier were
burning out too fast. The bulbs were the flame-shaped candelabra type and
had long filaments with very little filament support. I couldn't find any
high-voltage problems which was my first thought; but while I was working on
the chandelier, there was a thump upstairs and the chandelier shook so hard
that the various parts rattled. It was one of the kids in his bedroom
jumping off the top of his bunk bed onto the floor. That kind of shock when
the lamp is burning will kill any lamp because it welds several of the
filament coils together and the rest of the filament gets a higher voltage.
It then burns significantly hotter and fails faster.
Tomsic