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Trevor Wilson Trevor Wilson is offline
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Default Can and LED floodlight possibly be as bright as a real floodlight?

On 13/10/2014 6:17 AM, micky wrote:
Can an LED floodlight possibly be as bright as a real floodlight?

The fixture will be mounted about 24 feet above the ground so it has to
be bright.

The people who rate the one below say it's very bright, but have they
ever looked into a 100 watt incandescent floodlight? It's probably
blinding, so I'm not sure the raters' opinions are really comparisons.

The one below at Home Depot from Lithonia Lighting says it has "2
efficient 10-watt LEDs" where the two incandescent lights would
otherwise be. The picture shows two circular devices, each divided
into 3 120-degree parts, with what looks like a small concave reflector
with an LED in the middle of each part. I guess they are saying the 3
together use 10 watts. Are there really 3 1/3 watt LEDs, and is 10
watts from an LED as much light as 100 watts incandescent?? That's what
the floodlights use now, 200 watts total per fixture.

The maker's website
http://www.lithonia.com/commercial/2....VDrPJ 1fDuM0
says "Each head contains (3) 4780K high performance LEDs. Lumen output
of 1,222 is maintained at 50,000 hour life. LED driver is 120V and
operates at 60Hz."

I like the idea of LED, because it's very difficult to change the bulb
on one of my two** double-flloodlights.***, but not if it's not going to
light up the area.

Mostly what I'm looking for is a light that won't go on because of the
wind, but will go on when a person walks by.

This one, despite the high price, $116, only has 6 LEDs (2 by HD's
counting method!).
http://www.homedepot.com/p/Lithonia-...O-BZ/202598344

The same thing with three sets of three LEDs is 150 dollars, implying
that one group of three and the holder is $34
The same thing with photocell but no motion sensor is 98 dollars,
impliying that they're only charging 18 dollars for the motion sensor
and most of the price is for the LEDs.

Thanks.


Details that the electronics guys may find boring. Hey, everyone may
find them boring!
**The other floodlight in the back of the house I put in right under my
bedroom window, so I can just lean out and change the bulb. I wired it
from the receptacle just below the window, so little effort to run the
wires, and it sure looks better than several of my neighbors' who let an
electrician or handyman run surface Romex or conduit from the back porch
light, most of whom no longer have a back porch light.

*** It's chest high when I'm in the attic, so that's about 24 feet (?,
two story house, plus attic. The first floor is about a foot above the
ground.) and I don't have a ladder that long. What I've done to adjust
the light sensor and change the bulb is to unscrew the winged folding
toggle nut inside the attic, remove the big washer, disconnect the Romex
and tie a string to the end of the wire, and lower the whole fixture to
the ground. Do my work there, and pull tthe fixture back up. The hard
parts are getting the romex through its hole, and gettting the long
screw to go though its assigned hole (which is a lot bigger than the
screw, but still not easy to find) so I can screw the toggle nut back
on. I've done this twice with no more than 10 minutes each time trying
to get the screw through, but I fear some time it will take me hours,
and it woudl be nice if it used LED's and never burned out. But at 23
feet high, the light has to be bright!!


**In general terms, halogen flood lights are capable of between 5 ~ 10
Lumens/Watt. Good quality LEDs can manage between 100 ~ 120 Lumens/Watt.
I recently purchased a cheap, Chinese 100 Watt LED + power supply.
Without a reflector, it provides superior lighting to a standard 500
Watt halogen lamp (with reflector).

I took a couple of photos and found that the camera saw things
differently to the human eye. Although the halogen was distinctly yellow
and the LED very white, the amount of illumination was similar.

--
Trevor Wilson www.rageaudio.com.au