Ultrafire 602C Seoul SSC 42180 extremely hot

[george74]

Hi there!
I am new to this and need some help.
I've just received my second one of these: http://www.dealextreme.com/details.dx/sku.2978
The first one gets quite warm after several minutes but it's ok. The one I got today gets warm immdiately and after 1 minute is so hot I can no longer hold it in my hand. What can be the reason for this? Can I do anything short of having it replaced? The 2 are equally bright btw.
Thanks!

 

[Gunner12]

Either the first one doesn't have very good heatsinking, or the second one has a short.

This similar light from KD seems to have more output on 1 AAA then the Ultrafire one with 1 AAA.

:welcome:

 

[george74]

Why should the first one have a bad heatsink? It doesn't get too hot.
Thanks for the link, may try it someday.

 

[Gunner12]

Does the LED shift blue with longer use(in the light that runs cooler)?

If it shifts blue, that is a sign of overheating for the Seoul P4 LED.

Which battery are you using?

LEDs can create quite a bit of heat. Presuming no short, a LED driven at a decent current in a light that size should heat up the light pretty well. Maybe not hot(depends on the current) but there should be a noticeable increase in heat.

If not much heat is felt, that means there isn't a good thermal path, or the LED is driven at a low current(then the light would be dimmer).

 

[george74]

I cannot see any color shift in either of the units.
The cooler one gets very warm after a couple of minutes, the hot one gets so hot that I can no longer hold it after only 1 minute.
I use the original batteries from the above link Both units seem to have exactly the same amount of light.

 

[Gunner12]

Besides a short, a bad driver, or a bad battery(probably not), there's not much else I can guess, I don't know too much technical stuff.