has anyone seen MK-R lumen per watt data?

[pepperdust]

hi guys,

I was thinking on xm-l2. then started thinking of the MK-R. I was thinking to reduce chip count, with MK-R. I know there not as efficient, but has anyone seeing any testing done on lumen per watt for the MK-R. I know someone was nice to post there findings on a XM-L2 T6? so just wanted to compare to that data to get a rough estimate what I was expecting to lose. was thinking to run the MK-R at 8 watts.


Thanks for any info

 

[A10K]

To anyone curious about comparing CREE LEDs, use their online tool: pct.cree.com
You can specify LED, brightness bin, temperature, and current range. No more drawing lines on the tiny datasheet graphs.

To your specific question, an MK-R is basically 4 XP-G2s in series. It operates at a much higher voltage/current curve than the XM-L2, and is much harder to focus due to its size. Without knowing what you are trying to make, its hard to give concrete advice.
An MK-R, because it runs at lower currents than an XM-L, will be more efficient at a given output--that is, a single XM-L2 running at the same output as a single MK-R will be less efficient. However, 4 XM-L2s in series will be more efficient/more bright than an MK-R, because each individual XM-L2 is more efficient at low currents.

 

[Hoop]

That Cree product characterization tool gives some seriously screwed up numbers. For instance I compared a XP-G2 to a XM-L2 and it says the XP-G2 produces 989 lumens at 1.5 amps and 4.7 watts whereas the XM-L2 produces 986 lumens at 3 amps and 10 watts.

 

[A10K]

Some people have reported bugs with it on their machines. I've seen issues with it taking some time to update the values in the chart, every time I've used it its given me incorrect brightness bin options, like R3 XM-Ls and U2 XP-Gs. I just tried the info you posted and am showing the XP-G2 (R5) at the proper 519lumens.... are you sure you don't have a multiplier setting, like 2 LEDs vs 1?