led drivers? what can i build with this?

[mrhasan]

12x60W LED can make you blind

For tank, it depends on their placement, tank size and depth. But it is obviously an overkill for 10 gallon :P

[Reef Puffer]

Originally Posted by mrhasan

12x60W LED can make you blind

For tank, it depends on their placement, tank size and depth. But it is obviously an overkill for 10 gallon :P

thank you. i guess what im trying to figure out is, are these things useful (im looking to light a standard 120 gal and 40 gal sump)? im a total noob when it comes to led (and reefing really in general), and dont even know where to start. these drivers are available and if the price is right, i figured i might be able to build a half decent fixture? what does it cost to build something like this? where do i start? how much would i save by using these drivers? would i be better off with a different driver entirely? what am i getting myself into? should i just walk away now.....

[SeaHorse_Fanatic]

If its over a 6' 120g then you should probably go with at least 4 units of 60. A lot will depend which emitters you use. Very high output/high efficiency CREEs will be more expensive but you need fewer.

I use 10w emitters and have 28 over a roughly 6' 165g mainly LPS reef with some sps. If I was going full SPS reef, I would probably add another 6 or 8 emitters. What I have now works very well for my application.

In your case, if you went with 10w emitters in sets of 6 per heat sink (i.e. 60w per heat sink/per driver), then you would have one every foot & a half or so. If you went with 5, then you would have them one every foot with 6" from each end.

If you're using 3w emitters, I would probably use more emitters, more heatsinks, but maybe not the full 60w per heatsink. My 10w have 110 degree spread so I get good coverage per emitter. 3w emitters will give you a different spread/coverage.

For instance, my EShine 60w Cree unit placed very close to the surface does not fully cover my RSM130 and if I raise it, I don't expect it to be intense enough at the bottom. These have 90 degree lenses. Each unit is roughly 16" x 6" wide. So I would need to use at least 4 or 5 over a 6' 120g IMO.

[SeaHorse_Fanatic]

BTW, forget using LED to light a sump. Waste of $$. A cheap clip on light with a 13w or 23w Phillips Daylight 6500k CFL bulb and you're done. Why spend a lot of money and effort to light a sump? Use the money on your display, not the sump.

[martinmcnally]

You will need to be careful with those drivers as they are up to 5A of current. Max for CREE LEDs is 1A or 1.5A for XML

In order to use those with CREE LEDs you would have to have at least 5 strings of LEDs in parallel to get that current down to an acceptable level. However you would need to plan on having more of that as if one LED failed in a string it would cause all the other LEDs to blow from over current.

Another limiting factor there is the voltage. Those drivers only put out a maximum of 12 volts. Each Cree LED has a forward voltage of approx 3.2 volts running at maximum power. So per string you could only have approx 4 LEDs. You are looking at a maximum of approx 24 LEDs per driver (6 parallel strings of 4 leds)

[martinmcnally]

You could also run 6 10watt LEDs per driver but they would have to be in parallel again because of that 5amp current output.

[mike31154]

If you're a total noob to building a LED set up, you might be better off getting a manufactured fixture. The best info I can up with after a quick search on these drivers is that they are a constant voltage, non dimmable unit. They output 12 volts DC and the current delivered will depend on how your LED array is configured.

http://www.usa.lighting.philips.com/..._Atlas2012.pdf

The safest way to use one of these drivers is to build an array using MR16 form factor LED bulbs that are designed to run on 12 volts DC. These little spotlights have built in circuitry to ensure they run at the proper current, independently of the driver output. They are currently available with up to 4 LEDs per lamp and are designed to replace the Halogen spotlights in use for task lighting or store displays. I considered using these before deciding on 10 watt multi chip LEDs for my DIY fixture.




These are available on the online auction site at a pretty good price, as are the sockets. Haven't checked the colours offered recently but the good thing about them is they are designed to run on 12 volts & don't require any additional heat sinking. Once the sockets are wired up, a burned out lamp is easily replaced, plug & play. Pictured is the 4 watt version so you could hook up about 10 to 11 of these to each of the 60 watt drivers you're considering. I haven't come across any builds for reef tanks yet using these & I suspect it's because of the limited colour selection. AFAIK they're generally only available in the warmer whites or 6000-7000K cool white.

Alternatively, as mentioned you could use 10 watt multi chip LED arrays since the forward voltage they run on is between 9 to 12 volts in the colours we typically use in the hobby. Red 10 watt multi chips run at a lower forward voltage & they would quickly burn out using this driver. Using LED with forward voltages of less than 12 volts (such as the 3 watt Crees commonly found in many builds) would be a tricky parallel/series build with this type of driver & if a couple of them burn out or short circuit it would create a disastrous chain reaction, eventually burning out the entire array. My own DIY LED build uses White, Blue & Royal Blue 10 watt multichips hooked up to 12 volt power supplies & manual dimmers. fo mo info here's a link to my build.

http://www.canreef.com/vbulletin/showthread.php?t=82206



Above is a photo of the 10 watt Royal Blue multi chips I'm using in my parallel build. Note that the maximum forward voltage is 10 volts for these so any constant voltage driver delivering 12 volts would need a dimming control between it and these LEDs. The 12 volt power supplies I'm using are adjustable down to just under 10 volts & I use a dimmer to bring that down to run these at around 8 volts.