Well first I have a couple questions.
How have the results gone? What CCT did you chose and why? What was the final voltage and current out of the supply? (LED watts not system watts)
I think my responses would be better responding to something new than revisiting all the things of the past but here are some highlights.
+Samsung doesn't keep this very current but they have a helpful calculator to see the trade-off in drive currents.
I would use the 560mm F series and multiply it out to be the higher boards since the calculator doesn't have the new stuff.
It also allows you to input ambient temp and Tc measurement. It will be a solderable dot typically in the center of the module. Take a thermocouple probe for you volt meter and solder it on there and measure once you've been up and running for about an hour. It will spit everything out you need to know.
Samsung LED │LED Components & Engines, Smart Lighting Solutions
+ Saw the link to the thermal tape. I could do a whole rant on that another time about bonding.
+ Samsung typically designs their modules to be able to run at their typ rated current without secondary heatsinks. This is why the F series is metal core and the higher output version is a wider mcpcb. I would always heatsink however and then do a Tc point measurement to see how you did.
+ I would always use a mcpcb (metal core printed circuit board) when you can. Drives me nuts seeing these grow lights with FR4 boards (typical fiberglass circuit board). If you're making a "high performance" product spend the couple dollars to use metal. Performance is way better.
+ Metal circuit boards pull heat out of the die of the LED better. You want to keep the die temperature down because as the die temp goes up the efficiency goes down. Meaning the better you heatsink the better your light output is. Also longevity of the LED improves as well as color shift. Yes LEDs shift color as they age. Increased die temp also lowers the forward voltage of the LED which can lead to something called thermal runaway in constant voltage systems. I'd stick to constant current for these type designs.
+ For your heatsinks try to find something that is anodized. Since these aren't water cooled and are quasi air cooled most of your cooling will come from emissivity of the heatsink. Compare commercial sheet (mil finish) vs anodized:
Emissivity Coefficients of some common Materials
+ Heat sink is more about surface area then about volume but volume helps move it similar to a pipe. Its a balance.
+ I agree with not trying to maximize the lifetime of the product since efficiency and/or technology will improve very quickly here. If you run 18hrs/day then 50000hrs is 7.5 years.
+ Don't pay any attention to the MTBF on the power supplies. Though helpful I'd just look at the warranty. Warranty is usually based on full load and highest ambient temp. MTBF is usually at 25C and a other situations. Warranty will tell you manufacturers confidence in the product.
+ HLG products are good in the fact they have high warranty. The other hidden benefit is their high efficiency. They are >90% efficient usually.
+ If you lose a string the other strings will pick up the current so don't max out. Also replacing the LED once you heatsink will be very difficult although I have some techniques.
+ I'd stick to only UL class 2 power supplies. I know no one wants to hear this. This would be HLG 100 watts or less. Class 2 means it is power limited if + and - of the output short as well as energy limited for fire. This of course is not fool prood and do your DIY at your own peril but this will help safety. For making a UL listed light you could only have an exposed circuit board like that if it were class 2.
Tried to keep it short
Anyways interested in your results.
