You know where I’m going @Ginger_Rick. Neighbor has a Harley shop in the barn…He’s got an awesome set of tools. 
. I’m a carpenter by trade , other hobby is vintage car restoration . Yes looking for a thin profile I’m lost on electric and light part. Just want to know what strip would be best for veg and flower with either 6 or 12 strips? Length needs to be 24” width can be up to half inch Light will be around 12” from canopy all the way around.
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Hah, sorry to lowball you with the hole drilling 101 there @Instg8ter! I didn’t know if you had a history with tools, still figuring out who people are around here.
I’m still no pro on what the hottest new strips are, it seems like lots of people are getting great results out of the Bridgelux line. The ones I just picked up from Future Electronics are just clones as I understand, and were available when the bridgelux were out of stock.
I’m planning to use the ones I’ve just gotten for a couple of 150w 2x2 flat canopy cabinets for friends. While I’ve had them sitting here waiting on those builds I’ve been playing with ideas for my eventual lighting upgrade in my UFO cab.
So I finally reached back in there with my tape measure, it came back all sticky. My current usuable vertical canopy is 16.3 square feet. That’s the back wall and the two sides, but when I upgrade my light I should be able to light the front wall as well and that will get me to to 23 square feet. Right now I’m running 450 watts of SIL bulbs, spread over 16.3 feet, for 27.6w per square foot. The plants are loving it.
I’ve often seen it suggested that you need about 40w per ft square when flowering under LEDs, but I’ve also seen people moving those lights up a lot higher above their canopy than I have space for in my vertical setup. I’ve also seen clever cats like @Mr.Sparkle talking about flowering in the 30ish range and doing fine in close quarters like he runs. Inverse square law and so forth.
The strips I got will run about 150w on 9 of them. If I wrapped all 18 that I have around a vertical hexagon I’d have 300w of leds, but spread over 23 sq ft I’d only get 13 watts per foot! That’s not chunky flower numbers.
But even if I double that, 36 strips, 600 watts, it’s still just hitting 26w sq ft! And at that point I’m running 36 strips 20mm wide, so I end up with a hexagon that is 9-1/2" wide with 4.75" faces. Bigass hexagon.
So I’m still doing the math, and it honestly seems crazy to me. From a lot of what I’ve read 26w per sq ft should be too low for flowering, but I’m running just over that right now and things look good. Of course my gals are real close to their photon sources, and so again the inverse square law comes out. But no matter how I look at the numbers it always seems like 600 watts in a wardrobe cabinet seems impossibly high, and yet 26 watts a square foot seems unfortunately low.
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I’m running 54w/sqft and fuck me that is a bright bitch in a 4x4
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The Gen 3 Bridgelux slim lines are 1/2" wide, that might help with the size of the hexagon when going to 600 watts.
Cheers
G
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this should be on the outside of your tent
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How much space have you got between your lights and your canopy?
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Ah ha! The strips I’ve got now are 20mm, so 0.78 inch. That extra 0.28 inch will end up making a big difference, thanks! Now to look up gen 3 bridgelux, clutch my wallet, and weep…
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Rick, I’m sure you are aware of the inverse squares law on these lights. Since you are running mere inches from the lights, 13-watts/square foot will likely be plenty, you just wont have good penetration.
Not that part of me wouldnt love to see you cram 600-watts of strips in there. 
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Remember that calculations of the inverse square law must be modified slightly when you have multiple light sources. It’s not as straightforward as a quarter of the “power” for each doubling of distance from a single point source, especially when you have thousands of point sources, such as builds using strips or QBs.
You waste much of the energy of photons due to absorption when they hit any surface other than a leaf. Quite a bit, in fact, which is why you run strips low to the canopy and try to minimize wall losses, which can be 10-20% or more. If we’re OK with losing that much to walls, or if we’re OK with losing efficiency in using budget drivers that operate at 3, 5, 10, or 20% less efficiency than the best in class drivers, why do we care about using efficient LEDs? Why not just go back to bulbs, if you’re prepared to accept those losses?
I would still recommend around 25w/sqft of current high efficiency white midpower LEDs run at or near nominal current (July 2020), since most strips in this category are going to give you a lot of photons per joule in a good spectrum. As you mentioned, @Ginger_Rick, Bridgelux is the current king of the hill in a cost/benefit calc. They’re testing really, really well for the price.
Also keep in mind that the nebulous conventional wisdom of “penetration” is also modified not just by the necessary changes to the inverse square calculations when using multi-point light sources, but also by specific parts of the photosynthetically active spectrum. It’s now known that green, yellow and far red spectrum photons can travel through multiple leaves. This is a double-edged sword due to certain plant species’ response to various ratios of these wavelengths to each other, e.g. far red shade avoidance, but is generally a good bit of info for the conscientious DIY strip builder.
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Good points all!
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Those bridgelux gen3 do look very interesting, still need a load of them in a flowering chamber though. Just had an idea for them though if anyone’s interested. It’s based on a refrigerator grow.
You take an old chest freezer, strip out the internals, pump, insulation etc leaving a steel box with a lid.
Stand the thing on end, the lid then becomes the door, cover the inside with those gen 3 strips and the metal sides become the heatsink 
i might have to do this at some point cos i think it’s got potential
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20-25w/sqft from the wall 
or 18-23w/sqft at the strips but thats just where im currently running and also autosflowers.
both @ReikoX and @nube bring up excellent points.
Also consider led bulbs are less efficient that say new quality strips so much so you could probably reduce your wattage usage by 40% for similar light outputs of what you have now, so the common wordage of saying 30-35w/sqft will get lower and lower over time as efficiency goes up which is counter to how most people think in that if they can provide more power then they should provide more which can be detrimental.
I use to personally aim for the 40-45+w/sqft range for any leds i was doing, then started to reconsider and recommend the 35w/sqft range for LED SIL’s, now though even though i initially built my cabs to run in the 35-40w/sqft range, im now only using half to 3/4’s that so heck if i know what are good levels.
You may be surprised with what can be achieved with low amounts, but it comes down more to working with the plants to let them be the best they can without fighting them too much, its a balance i’ll be perpetually working on ;).
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Roughly 12-14 inches
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So where you say a 3p3s array I’m reading that as a 3 parallel 3 series array, so, 3 strips wired in parallel, 3 groups of these wired in series from the driver, correct?
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yes 3 in series then 3 of those stings in parallel just cause those strips run at 34ish volts and 525ma at nominal but their current max ratings aren’t that much more than their nominal ratings at least spec sheet wise, so if one string happened to fail the others would still be under max ratings and operable.
Math wise 3 strips in series would put them just under the 107v max on the M series driver “34v x 3 = 102v” and then running three of those strings in parallel would split the 1400ma / 3 = 466ma a string, so they will be running a little less than their nominal ratings but pretty close, and you should be able to tweak it a bit more current wise and still fall in the recommend performance region on the driver as shown in its spec sheets, but id just run it without fiddling with anything, apart from your dimmer pot.
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Thanks man, that’s the way it seemed to math out to me as well, but I did not sleep well last night and figured I’d double check I wasn’t missing something obvious.
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I got my order with the last of the parts I needed for this build today. I decided I would build a breadboard just to make sure everything was going to work as I had designed it. The first thing I did was unpack everything and, carefully, populate the board with the LDD drivers. The power supply had a big sticker on it that said to check the voltage switch before plugging in. Good thing I did, it was set to 220 VAC. Next I wired each group of two strips in series. Each group of two was then wired to the a channel on the board. Finally I set the jumpers so that the PWM is disabled and the boards run at full power. I plugged the light in and everything worked. I nearly went blind taking this picture.
My Bluefish Mini hasn’t shipped yet, but I decided to go ahead and use my standard Bluefish controller for the time being. If you do this, be sure to switch the jumpers on the Bluefish controller to run at 5 V instead of the default which is 10 V. Once I hooked up the PWM outputs and changed the jumpers on the boards, I started to play around. I was only able to get three channels to work at one time no matter what level I set them to. Unless one channel was at 0, the other channels would dim. Turns out the negative terminal of the PWM needed to be grounded on the DC side of the power supply. Once I did that, everything worked as expected. When I plugged in my Kill-a-Watt meter, I was reading about 124 Watts from the wall, 109 Watts at the strips.
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Do they have them in 24”? How would I wire 6 together with dimmable controller for 120v 20amp circuit?
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The Seouls Mr Sparkle mentioned above? yes, they are 22".
I’m ‘away’ from home base until Sunday night so limited access. Let me work it up for you then.
Cheers
G
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OK, looking at the Seoul SMJD-3618072C-xxN1 strips
36V, 840mA, 30W
The options are:
6 parallel = 5.04A, 35.5V use Mean Well HLG-240H-42B ($72.82 in stock @ Digikey)
Digikey P/N 1866-1843-ND
2 Parallel strings of 3 (1.68A, 102.6V) use HLG-240H-C1400B
6 in series (0.84A, 205.2V) use HLG-240H-1050B
Use the first option, 6 strips in parallel - it is much safer.
Cheers
G
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