At Ghetto Labs, progress is measured in empty Tecate cans and sleepless nights toiling away on fabricating lights. Drilling and tapping hundreds of 6-32 holes or soldering joint after joint can be mind numbing, but sometimes that's exactly what you want.
After experimenting with a few different heat sink designs and a fuck ton of COB LEDs off of eBay, the lights are really beginning to take shape. So far, work is complete on two identical veg lights, along with the first of two flower lights. Things are hacked and slashed together in true basement engineering fashion, but all in all, we're rather pleased with the results.
Power
Power is all sourced via cheap Chinese power supplies. We've settled on 48V as it provides a nice mix of voltage to string multiple LEDs together or run single high power chips. Combined with Meanwell LDD drivers, one really ends up with a whole lego playset that can be tweaked infinitely do fit any power requirements of a particular chip.
These supplies aren't without their troubles. We've had to replace a few capacitors and deal with a few blown fuses. For $45 for a 400W unit though, its sort of expected.
Drivers
Everything is driven by Meanwell LDDs. These things are amazing. 52V input, 1A output and 97% efficiency? Fuck yeah, count me in. Add in that you can score them for like four dollars and some change each at powergatellc.com and you can see why we like them so much.
For a few bucks more, we had some PCBs fabricated to ease the assembly.
Heatsinks
We got super lucky here and were able to score a lot of twelve 9.25 x 5.75 aluminum heat sinks off eBay for a pretty good deal, about $50 total. They had a few holes already drilled and some excess thermal paste on them, but for the money, they were going to work fine.
LEDs
This is the biggest crap shoot ever. We've bought a ton of random crap off of eBay, some good, some not so much. Unless you're buying name brand lights from a reputable source, you never quite know what you're going to end up with. Surprisingly though, about 2/3 of our output comes from cheap China COBs.
Veg Lights
To fill a 2' x 4' tent, we run two 20 x 10 fixtures, mostly identical. Each fixture consists of two heat sinks. Each heat sink carries one CXA2011 5000K and 5 10W COBs of various colors . Each light runs about 130W for the diodes, with an additional 25w going to the 4 70mm fans. Surface temps average at almost 100F at the diode junctions, 80F throughout.
These CXA2011s put out a fuckton of light. Honestly, they're probably more than enough by themselves, but since we have all this other crap laying around, why not add some diversity. Currently, the COBs are divided into 2x 2700k, 1x 6500K and 2x of these dope blue/white combination units. If given the chance, all 5 would be white/blue, the plants really seem to love them.
Flower Lights
The goal here was to make a fixture that could transition plants through their cycle, changing spectrum throughout the process to try to control some of the effects. We feel like more blue/white light early will reduce stretch and promote growth, while adding more red later will produce bigger frosty results.
We built the flower lights with this idea of shifting spectrum in mind. Each LDD has been wired out to a toggle switch so that they can be individually turned on and off. At max, they consume about 180W of power (plus about 40W in fans)
The flower fixture is made up of 3 heat sinks. Unlike the veg lights, they aren't identical. Each heat sink has one Cree 2540 3000K, but that's where the similarities end. The rest of the space is used by a assortment of Luxeon red and deep red, along with various red and white COBs. Depending on which LEDs are switched on, the color varies quite a bit. At the end of the day though, the entire output of the light seems to resemble a HPS, at least to my eyes.
So far, max power consumption of the fixture hovers around 180W with 35W of fans. Surface temps are slightly lower than the veg light at 93F, likely due to the use of 80mm fans over the 70mm used on the veg lights.
After experimenting with a few different heat sink designs and a fuck ton of COB LEDs off of eBay, the lights are really beginning to take shape. So far, work is complete on two identical veg lights, along with the first of two flower lights. Things are hacked and slashed together in true basement engineering fashion, but all in all, we're rather pleased with the results.
Power
Power is all sourced via cheap Chinese power supplies. We've settled on 48V as it provides a nice mix of voltage to string multiple LEDs together or run single high power chips. Combined with Meanwell LDD drivers, one really ends up with a whole lego playset that can be tweaked infinitely do fit any power requirements of a particular chip.
These supplies aren't without their troubles. We've had to replace a few capacitors and deal with a few blown fuses. For $45 for a 400W unit though, its sort of expected.
Drivers
Everything is driven by Meanwell LDDs. These things are amazing. 52V input, 1A output and 97% efficiency? Fuck yeah, count me in. Add in that you can score them for like four dollars and some change each at powergatellc.com and you can see why we like them so much.
For a few bucks more, we had some PCBs fabricated to ease the assembly.
Heatsinks
We got super lucky here and were able to score a lot of twelve 9.25 x 5.75 aluminum heat sinks off eBay for a pretty good deal, about $50 total. They had a few holes already drilled and some excess thermal paste on them, but for the money, they were going to work fine.
LEDs
This is the biggest crap shoot ever. We've bought a ton of random crap off of eBay, some good, some not so much. Unless you're buying name brand lights from a reputable source, you never quite know what you're going to end up with. Surprisingly though, about 2/3 of our output comes from cheap China COBs.
Veg Lights
To fill a 2' x 4' tent, we run two 20 x 10 fixtures, mostly identical. Each fixture consists of two heat sinks. Each heat sink carries one CXA2011 5000K and 5 10W COBs of various colors . Each light runs about 130W for the diodes, with an additional 25w going to the 4 70mm fans. Surface temps average at almost 100F at the diode junctions, 80F throughout.
These CXA2011s put out a fuckton of light. Honestly, they're probably more than enough by themselves, but since we have all this other crap laying around, why not add some diversity. Currently, the COBs are divided into 2x 2700k, 1x 6500K and 2x of these dope blue/white combination units. If given the chance, all 5 would be white/blue, the plants really seem to love them.
Flower Lights
The goal here was to make a fixture that could transition plants through their cycle, changing spectrum throughout the process to try to control some of the effects. We feel like more blue/white light early will reduce stretch and promote growth, while adding more red later will produce bigger frosty results.
We built the flower lights with this idea of shifting spectrum in mind. Each LDD has been wired out to a toggle switch so that they can be individually turned on and off. At max, they consume about 180W of power (plus about 40W in fans)
The flower fixture is made up of 3 heat sinks. Unlike the veg lights, they aren't identical. Each heat sink has one Cree 2540 3000K, but that's where the similarities end. The rest of the space is used by a assortment of Luxeon red and deep red, along with various red and white COBs. Depending on which LEDs are switched on, the color varies quite a bit. At the end of the day though, the entire output of the light seems to resemble a HPS, at least to my eyes.
So far, max power consumption of the fixture hovers around 180W with 35W of fans. Surface temps are slightly lower than the veg light at 93F, likely due to the use of 80mm fans over the 70mm used on the veg lights.
