So, what is "SBCFL"? Do I have to look for something specific on the package?
Also, this fixture has an option of running the bulbs at "half brightness" for 
specified periods.  Assuming I can find dimmable CFL floods, are there any 
cautions with their use?
Self-ballasted.  Kind of redundant, as all COMPACT (the "C" in CFL) 
fluorescents are self-ballasted.  No, you don't need to look for anything 
specific on the package.  Main thing is to make sure that the actual power 
draw is 30W or less (though the light output rating will probably be listed 
as much higher, like 80W or something) and that the CFL has the same type of 
base (the screw part) that your fixture is compatible with.
> Also, this fixture has an option of running the bulbs at "half brightness" 
> for specified periods.  Assuming I can find dimmable CFL floods, are there 
> any cautions with their use?
OK, don't know if dimmable CFL floods exist. I'd be surprised if they do.
I'd suggest that you NOT use the half brightness feature for CFL floods. 
First, you have nothing to gain by doing so.  CFL floods are not as bright 
as other floods to begin with.  So they are about "half brightness" right 
out of the box*.  If a dimmable version of a CFL flood existed, I'd have to 
ask WHY?!?  Also, the only reason to run the flood at half brightness would 
be to save energy.  But you are saving better than 50% of electricity just 
by using CFL floods.  (assuming you are willing to put up with decreased 
brightness, see below)
Also, the ballast in the self-ballast CFL flood will require full voltage to 
work properly.  If you reduce the input voltage to the CFL flood (by using 
the "half brightness" setting), one of two things will likely happen:
1)  Nothing (the bulb won't light)
2)  Bulb will light, but lifetime of the CFL flood bulb will be GREATLY 
reduced
*  CFL bulbs (including CFL floods) are rated according to their 
incandescent equivalent, but those ratings are greatly optimistic.  For 
example, if you get a "100W" CFL that uses 27W of power, the light output 
would be roughly equivalent to a 50W or 60W incandescent bulb, but the CFL 
manufacturers want you to believe that it is a good replacement for a 100W 
incandescent.  To truly get 100W incandescent brightness, you might need a 
"150W" or more RATED CFL, which might draw 50W or more of actual power.  So 
in the end, you might be wondering if it's even worth it to pay extra for 
the CFL?  I mean, if you get equivalent brightness, you really aren't saving 
all that much, in terms of electricity usage or money.  I prefer CFL for 
other reasons though.  I've had CFLs last for several years while similar 
incandescent bulbs are doing pretty good to last for several weeks.  Some of 
my floodlights are mounted about 20' off the ground on the side of my house 
(very hard to reach, even with a ladder).  Not to mention the ordinary 
indoor fixture at the top of the stairwell where NO ladder can reach, 
easily.  In these locations, having a bulb last several years is a GOOD 
thing, and the slight energy savings is just an added bonus.
Thanks!
> OK, don't know if dimmable CFL floods exist.  I'd be surprised if they do.
"Dimmable" CFLs exist, but I've only used a couple of them to avoid having to 
replace dimmer switches already installed.  As you noted below, they didn't last 
very long, now that you mention it...
> I'd suggest that you NOT use the half brightness feature for CFL floods.
. . .
> Also, the ballast in the self-ballast CFL flood will require full voltage to 
> work properly.  If you reduce the input voltage to the CFL flood (by using the 
> "half brightness" setting), one of two things will likely happen:
. . .
> 2)  Bulb will light, but lifetime of the CFL flood bulb will be GREATLY 
> reduced
OK. Thanks for the info.
Motion sensor floods are a bad application for CFLs.
  Cold cathode CFLs do well there (lack of starting-related wear, even 
used in marquees in Las Vegas!), unless the temperature is below 90-95 F 
(32-35 C) in which case they need time to warm up from "seriously dim" 
unless they are on a lot and have been for the previous several minutes.  
Cold cathode CFLs also mainly come in wattages around 8-9 watts or less, 
and are less efficient than the usual hot cathode ones if the wattage is 
over 4 watts.
  The cold cathode ones usualy have longer life expectancy of 20,000-or-so 
hours.
  Bottom line:  For motion sensor floods, use incandescent.  If they are 
on so much as to deserve a more energy-efficient lamp, then ditch the 
motion sensor.
  Beyond that - see if you can find an LED lamp rated for dimmers and 
electronic switching devices - then you can put an LED lamp in your motion 
sensor floodlight.  LED lamps have no need to warm up and do not 
suffer wear from starting.  Good luck finding one more than half as bright 
as about 50 watts incandescent floodlight equivalence, regardless of what 
is claimed.
Good Luck,
 - Don Klipstein (d...@misty.com)
Only true of ones with screw bases.
Most without screw bases are not self-ballasted. Major examples are:
PLC-26/F26DTT
PLC-13/F13DTT, PL-13/F13TT
PLC-9/F9DTT, PL-9/F9TT
PL-7/F7TT
PL-5/F5TT
There are a few others
  Ballastless CFLs are popular in commercial installations, especially in 
recessed ceiling fixtures - one advantage is that the ballast is separated
from the heat of the bulb!
  There are also "dimming ballasts" for nice smooth great dimming of CFLs 
- requiring ballastless compatible CFLs!  (Along often-usually with their 
own related special dimmer controls)
  There are a few pin base SBCFLs (I have yet to see any) for use in
newer construction in California that has its own energy efficiency 
mandates as well as the "known to the State of California to cause cancer"
stuff...
- Don Klipstein (d...@misty.com)
Is it the repeated on-off cycles, or something else?  If I put CFLs in the 
fixture, I plan on switching the 'on' time to the max for each cycle, which is 
20 minutes.
>  Beyond that - see if you can find an LED lamp rated for dimmers and
> electronic switching devices - then you can put an LED lamp in your motion
> sensor floodlight.  LED lamps have no need to warm up and do not
> suffer wear from starting.  Good luck finding one more than half as bright
> as about 50 watts incandescent floodlight equivalence, regardless of what
> is claimed.
I suspect we'll see an evolution from CFL to LED for "normal" lighting in the 
near future, as the cost and color issues are resolved.  I haven't seen any such 
LEDs yet, but I'll keep looking...
I've had only one problem, and that was last week-- a very heavy
rainstorm, and I came home to find the glass on the outside of the
bulb (that's the glass case, NOT the inside part that's the actual
CFL) shattered.  I assume that the bulb was a little warm and cold
rain caused it to break, although it could've been something blown
against it or a bird flying into it.
The bulb still worked, but given that the outside glass was broken I
opted to replace it.
The CFL flood bulbs I've bought are essentially a regular CFL bulb
inside a glass case/reflector.
Shaun Eli
www.BrainChampagne.com
Brain Champagne:  Clever Comedy for Smart Minds (sm)
  If you avoid a lot of starts from the long ontime, then you won't have 
too bad a life expectancy issue.  But they are unlikely to save money in 
comparison to an incandescent that has little on-time, and you will 
probably still have the warmup issue.
 - Don Klipstein (d...@misty.com)
FWIW, I tried out a couple CFL floods that I had in the house.  They 
worked, but not properly.
The lights came on well before sunset, and did not turn off very often at 
all.  When they did turn off, the warmup time when they came back on was 
excessive.
I put a pair of halogen lights in the fixture, and it's back to normal.
Oh, well, good experiment...
That makes every screw-base CFL I ever saw a SBCFL.
 - Don Klipstein (d...@misty.com)