LEDgardener

Hello guys,

I'm wondering if a u-profile would be able to dissipate all the heat that a double Samsung led strip provides, any thoughts?

no matter what shape of heat-sink you use, below is my experience:
if the area(L*W) of heat-sink is doubled on that the strips or PCB board, then it should be workable;

StanLee wrote: ↑

Wed May 29, 2019 11:43 pm

Hello guys,

I'm wondering if a u-profile would be able to dissipate all the heat that a double Samsung led strip provides, any thoughts?

How hard are you driving the strips?

They have two series with double diodes, and multiple models per series. Also U-profiles differ both in width and in the length of the fins.

For sure it will run pretty damn hot and have a short lifespan. There are a couple of threads on RIU where they look at f-series temps at different currents and heatsinks

TEKNIK wrote: ↑

Thu May 30, 2019 6:04 am

StanLee wrote: ↑

Wed May 29, 2019 11:43 pm

Hello guys,

I'm wondering if a u-profile would be able to dissipate all the heat that a double Samsung led strip provides, any thoughts?

How hard are you driving the strips?

i was thinking about 75% of their maximum.

It's a shame that i cannot find any decent and affordable heatsinks in my region [EU/NL]. I was thinking about slapping the SI-B8U521560WW on a u-profile with dimensions 40x40x40x2mm.

I'm not sure of the specifications of the F series, how many watts per bar? You can use basic U shaped aluminum to heatsink most strip products, To give you an idea 20mm U shaped aluminum will dissipate around 40 watts per meter. I always recommend you run a oscillating fan across the bars to help with the cooling.

I am always trying to build the light with the most photons and the least price.
I attached a photo of I light I recently built using steel studs from a lumber yard.
Not sure if they use steel studs in your part of the world, but they are cheap and quite effective as a "U-Channel" heat sink!

I have some steel florescent fixtures that I converted to LED with Bridgelux EB gen II strips.

They work fine for me, but I'm running single strips at ~50% of their rated max.

Based on my experience, I would not recommend steel stud for the OP's application.

Steel is a poor conductor of heat, and those double FB's would likely need some 'active cooling' (fans) in that scenario.

2" or 50mm Aluminum U channel would be the minimum for passive cooling with those strips at 75%.

To run at max, you'll probably need to use something closer to a typical heat sink with fins, or supplement the 2" U channel with fans local to the fixture.

Here is a link to some testing user T-Time did with FB24's;

viewtopic.php?f=11&t=1852&p=11333#p11333

BuddyColas wrote: ↑

Thu May 30, 2019 10:28 pm

I am always trying to build the light with the most photons and the least price.
I attached a photo of I light I recently built using steel studs from a lumber yard.
Not sure if they use steel studs in your part of the world, but they are cheap and quite effective as a "U-Channel" heat sink!

Hi Buddy, good to see you are posting on here, steel does dissipate heat but not anywhere near as good as aluminum, you need a lot more surface area with steel, from memory it was 4X more to dissipate the same amount of heat. It's good if you are getting it for free though and have the room for it and can handle the extra weight. Fan cooled steel doesn't work too bad at heat dissipation.
As leds get better they can handle higher junction temperatures also.
When I first started with leds you really didn't want to push them above 65° junction temperatures. Now days 85° is quite normal with some going upto 120°

We may get to the stage where heatsinks are not required at all one day, we can actually do without a heatsink on many strips already if they are driven soft, the copper traces provide enough to do the job. I tend to use extra copper in my strips for this reason although it does add to the cost of manufacturing

If your in the EU u have less options. One solution that has worked great for me are 30x30mm 0.6mm thick L-bars that are meant to be bent over the edges of gypsum boards for protection.
I used them on a higher power vesta build by sticking two on opposing angles, so they form a 60mm U-channel. If you can find them they are dirt cheap.

Another possible avenue to check is active cooling. Digikey has great fans starting around 3e a piece. Fans got a bad rep because of cheap chinese LED quality, but actually air cooling is pretty powerful. In general air movement in the grow space make a huge difference in heatsink temperatures.

The heat tends to build up as you get closer to the strips max performance, there is quite a big difference between 75 and 100%