On Sun, 01 Jul 2007 06:05:11 GMT, Eeyore
wrote:



"Mr.T" wrote:

"Eeyore" wrote

You need at least a 23W CFL to match the output of a 100W incandescent.

Ony for a good one at the start of it's life. They get even dimmer with use
though.

The table here...
http://en.wikipedia.org/wiki/Incandescent_lamp#Power

Shows a 100W incandescent providing 1700 lumens.

In comparison some new CFLs I have claim only 1100 lumens for an 18W and
1200 lumens for a 20W.

The 11W CFLs claim 600 lumens and that makes them only slightly brighter
than a standard 40W bulb instead of equivalent to a 60W as claimed.

I do wish they wouldn't make these silly claims for them.

Me too, and those equally silly 8,000 hour claims.
Most of the CFL's I have installed make it to 9000 hours.
I mark the "in service" date on the base body. I have a few lamps that run
24/7 that repeatedly make it to rated time.
I have also had a number of DOA's (dead from the start) and a number that
failed in the first 30 days. Note: in all cases, CFL's were installed in open
fixtures and NOT on dimmers (or electronic timers).
Some long service time failures were spectacular (lots of smoke).

Non-CFL (AKA regular fluorescent) have starter failures that are more frequent
than CFL failures. These lamps are in locations that are not suitable for CFL
(Closed fixtures, High/low temperatures) , Yard lights, Bathroom fan and
Attic crawl spaces.


I haven't been counting the precise hours but the ones I've had have lasted a
long, long time.

Graham