10W COB Diodes: Choosing the Right Heat Sink for 100W LED Strip - Aluminum Profile Options

Question

Hello. For some time I have been struggling with the problem of applying cooling to the COB diode. I am in the process of designing a 10x10w LED strip, i.e. 100W one strip. The problem is that it warms up mercilessly, and I don't know how to choose a heat sink. I have a 3mm profiled aluminum strip, 4cm wide.
How to choose a heat sink and which one? Greetings Piotr.

jdubowski · Answer

Do not exceed the rated current of the diodes? Strip is a channel bar? Because a 40mm flat bar for a zicher is not enough. I advise you to look for typical radiator profiles.

398216 Usunięty · Answer

I have 4 pieces of 3W on a similar length C-profile - I think it is just for them. You want to give it 10x10W ... Definitely not enough.

jarek_lnx · Answer

Radiator profiles with a larger surface - with ribs, you can buy by the meter, you only need to know the length at which you want to fit these diodes.
The more LEDs on a smaller surface, the better the heat sink must be (more ribs, and therefore the lower the thermal resistance).

smigas · Answer

You will recommend a typical heat sink for cob 10w I have in the plan as I gave, I just do not know where and what heat sink to look for, what surface, I do not hide that thermal stability is important for me. Near the water pane

jdubowski · Answer

On Allegro, look for ALUMINUM RADIATOR 100X100 MM 10X10 CM FOR LED. Try 2xCOB10W there and check if you can add a third one.

smigas · Answer

Is it normal that the cob diode heats up about 70
Degrees from the ordination side. The back part of the heat sink radiates nice heat and the heat sink's heat constant is 40 degrees
The cob diode is a type like the picture on the diode I limit 4ohm 4w
Please help

398216 Usunięty · Answer

LED is not an Easter egg. 70 * C is a bit much. The higher the temperature, the shorter the service life. Besides - you can't connect diodes in series? You can't use a DC power supply instead of resistors? You've probably chosen the least favorable combination.

smigas · Answer

I have the power supply as in the first post, it was 12 V impulse. And the LEDs in each combination are very warm, there is an option to reduce the heat sink heat because the condition is unbearable. IN

smigas · Answer

Even with a cube type heat sink, the diode gives 10 minutes, the diode is on the heatsink as in the attachment. Maybe the current flowing through the diode is too high, how to limit the currents in my case.? Where to find and how to choose a current limiting driver.

Freddy · Answer

This is a normal 12V power supply, not a LED power source.

smigas · Answer

Can I connect a led driver to such a power supply, such as "DREPER DRIVER LED 300W CHARGER" as shown in the post from a well-known one to stabilize the current dk diode requirements? On the diodes. I do not know much power and I would like aquarium lighting. Do it and just occasionally bought a power supply and cob diodes 20 pieces 10w

Links to Allegro removed - ANUBIS

398216 Usunięty · Answer

Measure the voltage at the diode and the current that flows through it. The power that comes out of the calculation must be separated and somehow it should be discharged from the LED structure into the environment. It's so simplified. It is not possible that the LEDs do not heat up at such power ...

smigas · Answer

The diode draws 1.16a current at 12.24v. The 0.59v voltage drop diode heats at this voltage maximum high until it fears after about 35s. How will I give a 2 Ohm 2w resistor the diode gets 0.76a. As the heat sink and surface are calculated, I admit that I am green in this topic

At 20 Ohm and 2w and 11.34 voltage the diode heats up much less so that after 30 min it is slightly warm. The decrease in brightness is small. The current flowing through the diode is 150 ma, please help me choose the right resistors and power, if a calculator is available or should I choose the experimental one

jdubowski · Answer

12.24V measured on the diode? 1.16A * 12.24V = 14.2W You overload the diode by more than 40%. Increase the series resistor. Is the drop on the resistor? And what is the tension on it in this case? Assuming that in the worst case the same as before, it emits on it 9.3W - safe value. At 11.34V and 150mA, 1.7W is separated from the diode. If the drop in light flux is small, then either you are wrong in its subjective assessment (activate for comparison two diodes next to each other) or the diode has already been masked with high currents. This calculator is now built into every operating system (on windows you have calc.exe) For calculations you need the nominal parameters of the diode - two of three values - power, voltage, current and voltage of the power supply.

Freddy · Answer

This diode requires a power source, not resistors. The current consumed by the diode changes significantly as the structure heats up.

smigas · Answer

What is the difference between the current source and the resistors that limit the diode operating current?
When using 21 Ohm 2w, the voltage dropped to 11.21v at the moment after 3 hours of diode operation, the diode has 45 degrees constant temperature on the size plate in the attachment. And i draws 140mA which causes an acceptable decrease in brightness.

Freddy · Answer

The current source maintains the current at a set value.
Resistors do not provide this at all. The LED during operation heats up, and the flowing current is strongly dependent on the temperature. Indirectly, because Uf changes.

nici · Answer

Do you give paste on the diode and heatsink interface?

smigas · Answer

Yes, I used the paste as in the attachment and today I will make the whole 10 led strip 10w and 1.16a each and I will lower the voltage until a satisfactory effect is obtained.

10W COB Diodes: Choosing the Right Heat Sink for 100W LED Strip - Aluminum Profile Options

Post #1

Post #2

Post #3

Post #4

Post #5

Post #6

Post #7

Post #8

Post #9

Post #10

Post #11

Post #12

Post #13

Post #14

Post #15

Post #16

Post #17

Post #18

Post #19

Post #20

Topic summary