9 Watt Cree High-Efficiency Light

LEDite

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Dec 6, 2002
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Dallas, TX
It may be ugly....., but it is very efficient.

9 Watts on my wattmeter. Three Cree Q2's running @ 700 ma.

95% efficient switching power supply.

ledbulb.jpg


Easily outperforms Compact Fl. of twice the wattage in down-throw applications.

Color still in the 6000° K range.

Now back to design on my 7 Cree Q5 AC light.

Larry Cobb
 
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LEDite

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Dallas, TX
DSE;

The switching power supply is one of about 20 I tested for efficiency at at 8.5 watts output power.

It was a 12 watt max design.

Larry
 

dse93

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Jan 6, 2007
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Ledite, where are you found this power supply ? Thanks
 

Ken_McE

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Jun 16, 2003
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It is unusually ugly, yet, somehow... it's beautiful too. Any idea how many lumens you get out of those nine watts? Is that radiator big enough? Do you know how hot it runs?

/trudges back to plain old stock CFL's...
 

LEDite

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The power supply is a Chinese plug-in supply by Leader Electronics.

It tested as the most efficient @ 11 volts and 700ma.

I would estimate lumens @ 500. After 1 watt for PS, overall efficiency of 56 lumen/watt.

Temperature stabilizes at 175° F (80°C).

Larry
 
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Kinnza

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Nov 15, 2005
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Location
Spain
Im doing some maths, and something dont match. Each Cree at 700mA consume about 2,5w, three leds sum 7,5w. Up to 9w, rest 1,5w. 1,5/7.5=20% losses at the driver. Far from 95% efficiency.

The temperature cited, its of the heatsink?

Anyway, good work
 

LEDite

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Location
Dallas, TX
Kinnza;

The 95% efficiency was for the electronic switching power supply only.

The Cree's actually are running over 700 ma. I figured ~ 8 watts for the LED's.

The temperature was measured at the top surface of the LED's.

Larry
 
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