DIY LED Using 10 Watt Arrays

[bkelly]

HI Mike Thanks for bringing your LED to the swap and showing us, sorry i didnt get time to see it more. Unreal how bright they are.
brent

[mike31154]

Originally Posted by bkelly

HI Mike Thanks for bringing your LED to the swap and showing us, sorry i didnt get time to see it more. Unreal how bright they are.
brent

No trouble at all Brent, there wasn't much more to show. All I was able to do was get a couple of them fired up at your place, one blue & one white. It was a busy venue!

For what it's worth, I made a few photos of the set up over my tank this afternoon/evening. I'll try to get several more tomorrow with the T5HO & Halides for comparison, but just looking at the photos compared to real life, I must admit the photos don't really tell the story. Seeing the LEDs over the tank has given me more incentive to finish up the build & replace the old lights. Anyhow, here they are:

All LEDs running with the fixture 7 inches above water surface. Blues & Royal Blues set at 8 VDC, Cool White & 10000K White set at 9 VDC. So in effect they are all being driven at somewhat below their maximum forward voltage. Still very bright & the colours are blending nicely. Did not perceive any disco ball effect.



This one is only the 5 Blues on the center rail dialed down low, set at only a few volts with the heatsink fans barely turning.

[bkelly]

that looks great , should be cool if you get into programming/controlling the diff lightings.

[mike31154]

Originally Posted by bkelly

that looks great , should be cool if you get into programming/controlling the diff lightings.

Yeah, I don't have a controller at the moment, not sure I want one either. Current lighting is on digital timers & I was thinking the same with the LEDs. This is one reason (aside from the wattage requirements) I need more power supplies, so I can run each colour with it's own power supply on separate timers. But now that I've started toying with the dimmers, a more sophisticated/automated method of controlling & dimming the LEDs is certainly tempting. On/Off with just a timer might not cut it anymore! Not that the livestock will care, since it's all been doing fine without sophisticated controlling.... more for the hobbyist I guess! I simply can't get that excited over fixtures that offer overkill features like cloud effect & lightning etc. I love my EcoTech VorTech pumps, but could care less that the Radion lights can communicate with them. What the hell for? Dawn/dusk dimming would make me a happy camper, don't need any more than that. 'Want' & 'Need' are different animals, often associated with large variations in $$$$$.

[mike31154]

Decided to forge ahead & start using this fixture even though there's still a fair bit of work & experimentation ahead. A major part of the experimentation is of course how my critters react to the lighting change. Burned the midnight oil last night, pulled the old MH/T5HO monstrosity & hung the LEDs. Running them as is, with loose wires all over on only one power supply & 3 dimmers has it's limitations, but I figured the sooner I get started, the sooner I'll see how the livestock fares. The LED configuration with respect to numbers & colours is where I intended for the initial trial, so damn the torpedoes.

I started with the fixture approx. 12 inches above water surface this morning. The 12 volt power supply, set at just under 10 volts is on a single timer & changes in intensity are done manually, either with the 3 dimmers or raising/lowering the fixture. I cut some wooden wedges to mount the outer rails, giving them a 10 degree inward tilt. I'm hoping the increase in focus to center, away from the sides translates into less glass cleaning! I'll probably be moving the outer rails a fraction closer to the center to further tighten light spread & minimize spill over the sides where it's neither needed nor wanted. The Hagen 77 gallon is relatively narrow & my rock scape with corals runs pretty much down the center longitudinally. It will take some tweaking to find the sweet spot of LED spacing in conjunction with height above tank, but I don't think I did too bad with my initial guess in that regard.

The fans are definitely audible & although lower in noise level than those I had cooling the ends of my overdriven T5HOs, some of them have a mildly irritating high pitched whine. This may be due to the fact that they're running below rated voltage or simply because they're cheap, dunno. The more I bump up the voltage on the LEDs, the faster they run & actually quiet down a little. Might try cutting all the fan leads & running them full speed at the rated 12 volts to see how that works out.

I like the look, plenty of shimmer & great colours on the coral. The tank is more accessible since the fixture is mounted higher than the old set up. The fishes certainly noticed something was different this morning and were a bit shy, but in less than an hour they were behaving pretty well as usual. I have a spawning Maroon clownfish pair so it will be interesting if the lighting change has any impact on their schedule. It's been about 4 days since their last clutch hatched and the female should be about ready to put down another.

After a couple of hours, I lowered the fixture by 2 inches to 10 above surface & bumped up the voltage on all 3 colours of LED. That'll be my sophisticated, high tech dawn/dusk program until I get more power supplies & timers. Numbers are now as follows, measured at the input & output of each dimmer:

LED colour, Dimmer input VDC, Dimmer output VDC

10000K & 6000K White, 9.63, 7.98
Royal Blue, 9.73, 5.51
Blue, 9.83, 5.51

Not entirely sure why the difference in input voltage values, since a single power supply is driving all the dimmers & lights. I assume it's due to slight variations in wire lengths feeding the dimmers & probably the different number of LEDs being run by each dimmer. The dimmer running the Blues is driving only 5 LEDs, Royal Blues number 8 for that dimmer & the one working hardest is the dimmer running both the 10000K White & 60000K White which total 14. I'll have to keep an eye on that one since it's probably close if not over it's 8 amp limit. Haven't made any current measurements, but by underdriving the LEDs with the low forward voltages, they won't be drawing anywhere near their maximum of 1 amp, so should be fine.

Inserted my power monitor into the circuit & the fixture with voltages as set now is drawing 140-146 watts. Should equate to some useful energy savings over the long term, although it seems that my heaters will be running a little longer without the Halides doing their thing during the midday lighting period.

[mike31154]

Update time! Cleaned up excess wiring & secured it to safely continue using the fixture. So far it's working great with no duds & I'm able to blend/control the colours nicely with the 3 dimmers. I've ordered 2 more dimmers to split the 6000K whites from the 10000Ks. I'll be ordering at least two more power supplies to distribute the load & run each colour on a separate timer. The current config works fine until those parts are in, it simply means I need to manually adjust the intensity for dawn/dusk dimming every day. Colours on separate timers will allow basic dawn/dusk effect, but automatic dimming using additional electronics is something I'm contemplating for the future.

12VDC, 250watt power supply & three 8amp dimmers are now mounted on a board in the center compartment of the stand. Another dimmer will be added to isolate the 6000K whites from the 10000K whites. 14AWG single strand house wiring runs from power supply to dimmers. From dimmers up to fixture is 14AWG stranded hook up wire.


Top side of the fixture. Added 4 cedar slats to mount terminal boards for wire distribution. Drilled additional holes in the rails for rubber grommets to feed LED wires thru.


Ten of these 12 to 24VDC, 900mA constant current drivers for 10watt LEDs came in last week. Don't think I'll be using them on this fixture since there doesn't appear to be any adjustment on them. I test fired one on a spare 10watt LED & it worked great at regulating the current as advertised. Haven't tried running it downstream of a dimmer to see how it reacts to that, but even if it works, I'd need one for every LED & that would be a bunch more hardware to add to the fixture. Since the build is essentially a parallel hookup, with each LED seeing the same voltage as delivered by the dimmers, constant current is less of a requirement than for a series application where you're feeding a string of LEDs. They might still come in handy for when I set up a fuge or frag tank, since there's really no dimming requirement for those applications.


Photo taken last night directly at the LEDs. Don't recall what voltage I was running them at, but nowhere near max. & they were still very bright.


Had to run the two 250watt 14000K MH Plusrites yesterday while I was completing work on the LED fixture, so here's a tank shot to compare with the LED photo from last week. MH


and the LEDs. Nicer spectrum & more pleasing to the eye to me. Better blend overall & still underdriven. Not too shabby at less than half the power consumption of the Halides.


Very happy with how it's turned out & livestock appears to be adjusting without issues. Female Maroon clownfish spawned a couple days ago, so she's clearly ok with it. Will take some time until I know how the coral fares, but everything looks quite happy after a week under the LEDs. Have 7 Blue & 2 Royal Blues left over from the build, along with miscellaneous wiring, hardware & resistors I didn't use. The fixture easily lights a 4 foot tank, weighs only around 7 pounds & the cost of material is somewhere in the neighbourhood of $600 to $700.

[mike31154]

A little over a month now running the fixture. Not completely finished, but I've stained the wood & half attached some of the trim to make it a little nicer to look at. Still need to figure out how to cover the top without adding a bunch of weight & restricting air circulation to the heatsink/fans. Something thin & flexible I can sort of bend into a shallow dome perhaps.

Everything appears to be adjusting nicely to the LEDs, with no apparent issues, other than the green algae. Since this fixture is providing more blue light for a longer period of time, the green stuff is taking it on the chin & tank is looking better every week. All coral including several sps bits continue to grow. Will take more time to get a better idea of the rate, but just the fact that they're doing well is a good sign.

Latest photos. Fixture is dimmed down for morning dawn effect. Things get much brighter when I crank up the voltage.

[reefme]

How are you getting the reflectors and lense installed?

[mike31154]

Originally Posted by reefme

How are you getting the reflectors and lense installed?

I won't be using optics. Things are looking great without reflectors & lenses. I think the colours blend more effectively without lenses.

[mike31154]

Fixture running great since beginning April. Thought an update may be in order. I've added a second power supply allowing me to run each on a different timer to give a simple dawn/dusk scenario. Still no automatic dimming other than that. Added a fourth manual dimmer to allow individual control over each of the 4 different colour LEDs I've used. Two meters provide voltage monitoring through a couple of switches I added. The top voltmeter shows volts for the two left dimmers fed by the 250 watt power supply (Royal Blue & 10000K LEDs on the outer rails). The lower voltmeter monitors the smaller 150 watt power supply (6000K & Blue LEDs on the center rail). By using the DPDT switches I can toggle between monitoring the voltage provided through each of the 4 dimmers. Here's a pic of what it looks like at the moment.



All the 10 watt LEDs should be well 'burned in' by now and the only thing that has failed is one of the heatsink fans. Easy enough to replace since I have a few spares kicking around. Still running without any constant current devices, relying on the dialed down voltage to keep things safe. Intend to do some current measurements to see how things are matched between LEDs, but it's been working so well I wonder why I should bother. If one were going to cook, it surely would have done so by now.