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Art Todesco

Don Klipstein wrote:
In ,
wrote:

On Apr 27, 2:51 pm, (Don Klipstein) wrote:

I have this sinking feeling that dimmable screw-base CFLs at least
sometimes lack provision to have their filaments maintained at a proper
temperature when they are dimmed. I would expect some compromise in life
expectancy with severe or moderately severe dimming.

One scheme mentioned a lot in some thread in sci.engr.lighting earlier
this year is to have two sets of lights in a room - one for bright
lighting and another for dim lighting.

- Don Klipstein )- Hide quoted text -
There is no filament in a CFL.

All fluorescents except cold cathode types have a filament at each end
to use as an electrode. They have a coating that gets sputtered
(effectively evaporated), and much more rapidly if they are not at the
proper temperature. When that coating is gone, the fluorescent lamp does
not work too well (often not at all) anymore.

- Don Klipstein )
Kind of a matter of semantics. CFLs
usually don't have a filament as in
the long tubes. They do have an
electrode at each end. The filaments in
the standard tubes are used as heaters
to help in starting. CFLs use a
higher voltage that don't require the
pre-heater.