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

On Thu, 16 Oct 2014 20:30:12 +0200, Dimitrij Klingbeil
wrote:

On 12.10.2014 21:17, 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 manufacturer of the LED lamp has published some photometric data
(accessible via the link you posted). According to that data, the
luminary in question has a maximum output of 1165 lumens (lm).

That 1165 lm is not very much.

A normal (non-halogen) 200W incandescent lamp has a light output of 2500
lm (according to the datasheet for the Osram "Centra A CL 200"), and
that's a "mechanically rugged" type lamp with a thick filament that is
not even particularly efficient.

A 200W halogen incandescent lamp has a light output of 3500 lm (3520 lm
according to the datasheet for the Philips "Plusline Small 200W R7s 230V").


I had a halogen light there for a whlle, but the socket on one side
burned out, or got hot and crumbled. I didn't even think about
efficency when it was installed, or when I replaced it. Shame on me.

Depending on how efficient your previous lamp has been, you'll likely
need to either double or triple the LED lamp in order to match it.


I ended up getting an led fixture that rates itself twice as bright as
the url I gave in the OP. I'm not going to say what it is, because I've
learned from experience that one or more people will tell me it's no
good, and I don't want to hear that now, since I've already bought it
and may put ii in any minute now.

Regards
Dimitrij


Thanks for the informative reply. For the sake of electricity, I'm glad
I didn't get incandescent this time. Maybe no more lightbulb changing.

(I hope to go away for a few weeks next february and I didn't want to
wait until spring to fix the lights.)