Led temps

[Boonjob]

Whats the temp of everyones leds and heatsink?

I understand rule of thumb is if its too hot to hold tightly its too hot... But I have little to no feeling in my hands so this doesnt work for me rofl....

Mine run at 49c at peak dont get any hotter. This is accepatble in PC realms I assume safe for leds aswell... But if I need it to drop I will run a fan though I prefer not ATM.

[Wall_Tank]

I think 40C should be fine.   I keep mine less than 40C, I have a 40C thermal switch for cutout.

[Bluewater]

That is only about 120 degrees you should be fine with that. If it goes up much higher I would put a fan on it.

[kattz]

mine run about 90F.

[Wall_Tank]

I would say mine are less than 100F.   The 40F emergency cutout is in each array in case of fan failure.

[joncat24]

according to Rapid Led, anything over 105 is detrimental to the life of the led. I keep mine at about 92-95

[Bluewater]

That seems kind of low since a hot day in this state can get up to that. You can run computer chips up to 60 degrees C or 140 degrees F. But if that is what rapid says I guess that is it.

[Wall_Tank]

According to the Cree spec.  What is critical is that the Junction Temperature does not exceed 150C.   That is inside the chip.  So you have to transfer the heat out of the chip into the starboard, through the Heat transfer paste and into the heatsink.

So that is why it is more of a rule of thumb.

[Boonjob]

I read 90-150 f... Though obvoously the cooler they run the better I assume... I also read if tjey run too cold they can exhibit a color change which I think I see between when I turn kn the leda until they get up to about 120 degrees ghey seem whiter at 120...


Regardless the census suggests 90F... So I will be adding fans.

[jeremy]

I have three fixtures in the same room on different tanks. Ambient temp is 66F.  Temps from one of those laser temp reader doodads.

Fixture 1
  4.5"x9" with 9 RB Crees @ 990ma, 6 CW Crees @ 990ma, 5 UV @700ma, and generic 120mm fan running @6v = 95F
  The UV LEDs on this fixture have brown lenses and one CW has burned out...they are around a year old...can only assume this from heat.

Fixture 2
  6"x9" with 14 RB @ 990ma, 4 WW @ 990ma , 5 CW @ 990ma, 11UV @ 500ma, 1 Red, 1 Cyan, 1 Green each @ 500ma, and a Scythe 140mm 500RPM fan @12v = 76F

Fixture 3
  4.5"x5" with 3 RB, 3 CW, 3 Red, all @ 990ma, and a generic 80mm fan @ 6v = 75F

I've found that even a tiny bit of positive air pressure makes a huge difference in temp.

[Boonjob]

Everyone just using wall warts to power their fan units?

[Wall_Tank]

Everyone just using wall warts to power their fan units?

Some fixures yes.   I also use open frame power supplies in my closed fixture.

[Neogenesis]

I use a 5v or 7v wall wart on 12v computer fans over my frag tanks.  Running them at lower volts just makes them silent, but still move enough air to keep things nice and cool.  Worst case, grab a computer fan controller then you usually have some control over the speed of the fans, which is what I'm currently doing on my DT.  You still supply the controller 12v, but then it takes care of the rest.