1. Home
  2. Electronics Down Under
  3. Compact Fluoro's - operating position?

Compact Fluoro's - operating position?

I've heard stories of CFL's that gave decent life in only the base-up position, and died prematurely if mounted base-down.

Is this behaviour anyone's experience here, and if so how can one determine which if any will happily operate base-down?

Reply to
who where
Loading thread data ...

"who where"

** What utter crap !!!

** All CFLs run fine base down.

Hot air rises you know.

..... Phil

Reply to
Phil Allison

No, you are thinking about incandescents, these should be installed base up

CFL should be installed base down where possible, though In my experience, I have had no noticeable trouble using 18w and less CFL's base up in normal household light fittings that were originally used with incandescent bulbs.

Some of the larger ones - (such as those 60w ones Bunnings had a while back) may be a problem due to the greater heat involved, but have not tried them.

Reply to
kreed

The reports I heard were CFL's, and the rationale related to the location of the mercury when the lamp is started. Whether there was any truth to it is what I'm trying to ascertain.

It wasn't a thermal issue.

Reply to
who where

"who where"

** Now you tell us .....

What failure symptom is linked to this alleged mercury V gravity issue ??

All the CFLs I see fail because the filaments go open, the electronics fail or the glass breaks - none last long enough for the light output to diminish much.

AFAIK, mercury is absorbed into the white phosphor and turns to vapour soon as the tube heats up - there is always enough vapour at room temp for the lamp to light up OK - but not so if the CFL is very cold.

Try this:

Put a CFL in the freezer for 10 minutes and then plug it in and see how dim it is.

..... Phil

Reply to
Phil Allison

ElectronDepot website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.