Water Cooling LED's Discussion Thread

I didn't see the guys bucket, but most are plastic. So won't radiate much at all.

The 100w led lights in my last post were looked over by Big Clive. Specifically the one's with a yellow sticker at one end. They started at 100w but dropped to 71w as they chips regulated down the power due to heat. The chips reached 125c which was 110c over his 15c room temperature.

This is good news. That is hot enough to be worth cooling, while still not needing the cooling to survive. It's also next to no work. With little expenditure.


I'm very fond of RV pumps. £10 gets a 50w pump with 10 meters of lift. 1/2" hose just pushes on. Such a pump will circulate with quite some force. Good for trials. Long term a central heating circulator pump is the real deal. Less pressure, but harder to kill, and very quiet.


My next project is my 3rd air cooled Led system, but I'm still looking at this. One common goal is to get maybe 6 or 8 cob's together, to light a meter from a fixed point. So just a shoe box sized light, without a lot of connections.


The pic is the published data of my citizen 1212, though it's no way such a circle imo. I have laid a second over the top at 90 degrees. To look at lighting a meter from about half a meter above. The 30% gain in the middle, is over maybe 200mm of the canopy, so maybe the leds should be 200mm apart. Then the perimeter can be improved with the shade. It's work in progress, shared now as maybe it's been done?

Yeah, most of these cobs say 120 degree pattern, but real world shows most of the intensity straight down. I'm wondering how much of a difference the lens quality has on this beam spread? Is there a huge difference between mfgs, or are the results pretty standard? The lens built into the chips, not ones you place over the chips.

What is the distance to canopy with the 100w chips of yours? These 50w Ming & Ben are really micro-grow lights for sure. Considering using these for micro-greens after the first few runs.

I have my cobs about 300mm above, to cover about 500x500mm. That gives the most even spread. It still varies about 20% though.

I can't find the barn door 100s that use a single board. That is what I saw Big Clive test. I only find them with a pair of 50s. Which is a large footprint. I have figured that using two pipes, I can swap the rivets for long bolts. Putting a plate above the pipes. So the bolts pinch the lot together. No permanent glue solution. I'm seeing these 50w lights at £4 a pair, which is the cheapest things ever. I keep looking at these smart chip boards, and wishing somebody would use decent leds on them. In my mind, the smart chips are the best ballast option. Samsung the best leds. But nobody has bought them together. I'm tempted to buy these barn door lights, which are basically free. Then figure out how to fit better chips. Then I will have the only product in it's league. Best led's, power regulation based on heat, and no ballast box. Just a flimsy lightweight light.


It's so easy to take away nearly all the heat with air, that a water solution is getting rather specialist. Like using the heat to warm the ground in greenhouses. Or use the heat to warm the air intake. Or fertigation water where online dosers are used. Leaving the water at well temperatures, unless heated.

Air cooled lights that direct the heat straight to the filter, work well. You just buy square plastic duct, and put your lights in it.

http://www.aluten.net/mpe-tubes.html

I'm thinking about QB boards. With a cooling layer between the board and heatsink. Which you can use, or not. I think something like a cpu cooling block wouldn't be impossibly hard, using a sandwich of 3 plates, where the middle plate is little more than walls. Offering a good thermal path without any fluid, or the option of fluid.

I don't really want to cool with aircon. It's an environment issue.

Keep in mind when building your channels and hanging things, water is 8lbs/gallon.