LED Calculations

Triple Cree XRE Q5 at 1000ma

Min 107 x 2.25 x 3 x 0.92 = 664.47

Max 114 x 2.25 x 3 x 0.92 = 707.94

 

Triple Cree XRE R2 at 1000ma

Min 114 x 2.25 x 3 x 0.92 = 707.94

Max 121 x 2.25 x 3 x 0.92 = 751.41

 

Quad Cree XRE R2 at 1000ma

Min 114 x 2.25 x 4 x 0.92 = 943.92

Max 121 x 2.25 x 4 x 0.92 = 1001.88

 

Explanation.

Cree XRE R2 LED generates 114-121 Lumens.

The LED lumen output is not linear and slightly decreases as the current increases thus 2.25@1000ma not 2.86 as I previously thought.

Multiply by the number of LEDs

0.92 is the efficiency of the optic. (92% transmission)

 

 

Lumen8r-10W ~550 Lumens	Lumen8r-LED Triple Cree R2 ~720 Lumens	Prototype Quad Cree R2 ~1000 lumens