Old LEDs

[Bolek]

I still use old lights with P4 Cree led, sometimes eaven luxeon. There are not as bright as my new ones, but how is the efficiecy of old Cree ?

 

[yellow]

same current --> less bright --> efficiency worse
;)

the XR-E still is said to be the easiest to focus
(that whole construction should be "promoted" with the new emitter plates)

 

[xpitxbullx]

I still use my Surefire E2L Outdoorsman. Single stage KL1 head with a Luxeon III. 60 lumens OTF.

I am looking to upgrade it to an XPG soon, though.

Jeff

 

[nbp]

I still use some SSC P4 based lights. From the perspective of beam quality, it's probably my favorite emitter ever, even if not the most efficient or brightest.

 

[Bolek]

:thinking:I know that the efficiency is lower than e.g. XML but by which % ?

 

[Jthe5th]

XR-E P4 @1000mA you get 180L

XM-L T6 @1000mA you get 400L

XM-L U2 @1000mA you get 426L


Forward voltage is 3.7 for the XR-E @ 1000mA

Forward voltage is 3V for the XM-L @ 1000mA


That means:

XR-E P4 - 3.7W - 180L
XM-L T6 - 3W - 400L
XM-L U2 - 3W - 426L

On Li-ion batteries it's easier for the XM-L to maintain regulation compared to XR-E, becasue of the lower vf.

 

[Bolek]

Thanks.
So the XM-L T6 is 2.7 times more efficient that my old XR-E P4 @ about 3W. It's more than the ratio between efficiency of XR-E P4 compared to luxeon III