How hot do 3 Watt LEDs get


New member
The lens of the LED or the plastic lens clipped to the LED?

They run very hot... you have to have a heat sink w/enough capacity (surface area/fans etc) to cool them or they will fry. Don't ask me how I know ;) Suffice it to say I made a DIY retro fixture for my RIP BC29 couple years ago so I got to play around w/Cree LEDs a bit.

The plastic lens is fine, the lens on the actual LED can get pretty hot but not as hot as the other side of the chip or the immediate area on the heat sink if well bonded thermally (which it should be for it to work).

Temp wise its probably high 100s or close to 200 F if you don't cool them and thats pretty much their frying temp (or actually past it). They aren't suppose to be allowed to get hotter than like 120F I think, but that depends on the chip and I may be off by bit. I am referring to Cree XR-E's too so thats few years old.

Space :)