XP-G Star and die temperature

[Capo_au]

Hey all

Simple question, just how hot is 'normal' for an XP-G R5 on a 20mm star?

Even if heat sinked well it still considered safe if the star becomes too hot to touch while running at 1A?

Thanks :thinking:

 

[ahorton]

I've been wondering the same thing.

My experience is that even with great heatsinking, the top of the MCPCB gets pretty hot and starts to dim.

I feel more comfortable running these things at 700mA since

 

[Ekke]

Could you measure the temperature? I have one sitting on the copper tap that is mounted in an aluminium heatsink - without any MCB. With 1A it surely gets warm/hot (the heatsink), but I haven't tested this so much yet, and don't have suitable temperature meter right now..

 

[IMSabbel]

"too hot to touch" is normally 50-60C.

Lets assume 60C, and 4W power in the led. this will give junction temperature of less than 100C, which should be fine.