I've been monitoring the DIY LED thread on RC (http://reefcentral.com/forums/showthread.php?s=&threadid=1587273) for the past few months, and at the same time planning and folding everything that I'm learning from the thread into my own project. When I first started my 90g, I went with T5 lighting, but switched to 2x250w MHs 6 months later because I couldn't do without the shimmer. My SPS colonies were thriving with the T5s so I knew there was more than enough lighting; the problem was the lack of shimmer!
In April of 2008, the PowerBrite LED fixtures had just come out, and I bought one to see how well they worked. They did work, as long as the T5s weren't too bright. They worked great when only my Actinics were on, for example, but once the daylight T5s were on, they were pretty much washed out and the shimmer was not noticeable. The lessons I learned from that trial were that the 1w LEDs (60 lumens each) included in the Powerbrites weren't bright enough to overcome the brightness of my overdriven daylight T5s, and that the LEDs were spread apart too much. The LEDs were spaced roughly 3" apart on the 1' long fixture. I think the lights would've been more effective (as shimmer supplementation) if the LEDs were clustered together.
Fast forward to present day - more and more high-power LEDs have been coming out lately, so I thought it was perhaps a good time to give LEDs another try to supplement T5s for shimmer. I would love to get rid of my MHs and move back to T5s. This is my build thread. Maybe we can have more of this type of project in the club!
The OP of the RC thread used the Cree Q5 XR-E LEDs, and those are what I used as well. These LEDs produce roughly 200 lumens when driven at 700mA, which is what I decided to do. These LEDs can be driven up to 1000mA and get more light, but will also generate more heat. At 200 lumens, this is 3x the lumens each of the Powerbrite LEDs generate, and with the tight clustering I was planning, I estimated that I'd have enough light for a good shimmer. My plan was to build two LED clusters - each cluster with 3 LEDs mounted on a CPU heatsink forming an LED "spotlight", if you will.
My Bill of Materials is as follows:
6 x Cree Q5 XR-E Soft White LEDs premounted on Starboards (~$54 total from ledsupply.com)
1 x 3023-D-N-700 Wired BuckPuck LED Driver (~$15 total from ledsupply.com)
6 x 25 degree "narrow" lenses and lens holders (~$9 total from ledsupply.com)
2 x Thermaltake CPU Heatsink with fan (~$25 total from Fry's)
2 x 6-32 drill bit and tap set (~$10 total from Lowe's - I had to get a second one because I broke the first one
)
20ft 16ga stranded Primary Wire (~$5 from Lowe's) - only used a few feet's worth
1 x 18.5v DC 2.7A power supply (using an old Compaq Laptop charger)
Other hardware items (6-32 stainless steel machine screws, nylon washers, thermal paste, etc) I already had in my toolbox.
Here is the CPU heatsink I went with. I went over to Fry's looking for CPU heatsinks that had a good-sized flat surface to mount the LEDs and that also came with an 80mm fan. The one below fit the bill perfectly, and even better, there were two "open box" items so I saved another 65 cents or so on each!
alt="">
This particular heatsink had a copper base to enhance heat transfer from a CPU die, but I didn't need that. Plus, the copper base made the effective size of the heatsink smaller, so I just took it off, giving me a nice-sized flat piece of aluminum for the LEDs. I estimate I can fit 5 of the LED stars comfortably on the face of the heatsink.
alt="">
Using the LED starboards as guides, I marked off the locations of the screws, then took the heatsinks to work to drill the holes. One of the labs at work has a nice drill press that made drilling the holes a breeze! I then tapped the threads using a 6-32 tap set purchased at Lowe's. I ended up going through two taps. :-/ I broke one as I guess I was rushing it. Take it slowly, and stop and lubricate with 3-in-1 when you feel pressure while turning the tap. The taps will break easily from the torque if you force it.
alt="">
Even though my plan was to use 3 of the LEDs on each heatsink, I decided to go ahead and drill holes for 5 LEDs for possible future expansion. The picture below is of the 3 LEDs mounted on the heatsink. The pair of holes in the middle of the LEDs are for future expansion of a blue LED. I thought in the future, I could mount a blue LED there for moonlights. The pair of holes in the lower right is for a 4th white LED, in the event the 3 LEDs aren't bright enough. I applied a small amount of thermal paste underneath the starboard then used 6-32 machine screws with nylon washers to mount the LEDs. The nylon washers are very important as the heads of the screws can come in contact with the soldering pads on the starboards, causing a short-circuit.
I used 6-32 machine screws because that's what the majority of the folks on the RC thread used. Some used 8-32 screws which are bigger. The problem I ran into with the 6-32 screws is that the screws were too big to fit completely into the screw slots cut into the LED starboards. This wouldn't have been a problem if I had just spaced the holes slightly further apart, but it was too late and I had already drilled the holes. I ended up grinding the screw slots slightly bigger with my Dremel to allow the screws to go in all the way. One could use smaller screws, but I think anything smaller than a 6-32 machine screw will be harder to find at your local Lowe's or Home Depot.
alt="">
A quick note on the power budgeting - I decided to use 3 LEDs for each cluster (6 total) mainly because the LED driver I'm using (Buck Puck) can drive up to 6 of the Cree LEDs. Going with 3 each (6 total) allowed me to use just one Buck Puck and keep my costs down. If I found that the 3 LEDs weren't bright enough and had to go with a 4th or 5th LED per cluster, I'd have to get a second Buck Puck to drive the additional LEDs. But before I go to a 4th or 5th LED, I'll probably try driving the LEDs with 1000mA as opposed to the 700mA I'm using the first time around.
As for the Compaq laptop charger that I'm using as a power supply - as I mentioned earlier, it outputs 18.5v DC and 2.7A. Each Buck Puck can drive up to 6 of the Cree LEDs wired in series, but in order to do this, you need a 24v DC power supply (each LED has a forward voltage drop of 3.5v at 700mA which means 6 x 3.5v = 21v, plus 2-3 volts per the mfr guidelines). Fortunately, with my setup, I will be wiring the LEDs in each cluster in series, then wire each cluster to the Buck Puck in parallel. With this setup, both clusters can be driven by the same Buck Puck. Also with this configuration, I just need the power supply to output 3 x 3.5v = 10.5v, so I was able to avoid buying a power supply and save ~$30.
In looking around the house for power adapters, etc. I noticed that laptop chargers and printer power supplies are great power supplies for driving LEDs. They all pretty much output ~18v DC and >2A which is perfect for powering LEDs.
Here are the LEDs in one cluster all wired-up! As mentioned above, I wired the LEDs in series. Each of the clusters will then be wired in parallel to the Buck Puck.
alt="">
A quick note on soldering - you can do it at least a couple ways that I can think of. You could either solder the wires with the LEDs off the heatsink, or solder the wires with LEDs already mounted on the heatsink. I chose to do the latter because it would be easier to get the wire lengths right, and solder the LEDs in the right positions. If you do the former and solder the wires before the LEDs are mounted, you might have to tweak/bend the wires a little bit to get the LEDs aligned with the screw holes. Doing this would put stress on the soldering pads on the starboards and could break them.
The problem with doing the soldering with the LEDs already on the heatsink, is the heatsink sucks all the heat from the soldering iron, making it tougher to get a nice, clean solder joint. My 25w pencil soldering iron didn't work too well (couldn't get hot enough with the heatsink sucking all the heat out), and I had better results with my 100w soldering gun.
The picture above also shows the lenses mounted on two of the LEDs. I wasn't sure if I was going to use the optics, but I went ahead and ordered them as they were fairly inexpensive. The lenses I ordered are 25 degree optics. The lenses snap into lens holders, and the lens holders have to be somehow mounted to the starboard. I used superglue to attach the lens holders to the starboard. I ended up having to mod the lens holders themselves because there wasn't enough clearance under the holder for the solder joint. I pulled my Dremel one more time to grind the underside of the holders. The pic below shows the underside of the holders - the one on the left is unmodified; the one on the right has been ground out a bit.
alt="">
I then repeated the process above a second time for the other cluster to make two LED spotlights. I laid out the LEDs in mirror images to each other as both clusters will be on either end of the tank, pointing inwards.
alt="">
In my tests, the Buck Puck never seemed to generate very much heat, so having it attached to a heatsink wasn't important, but just affixing it to one of the heatsinks seemed like a simple way to do it. I just used some superglue to secure it in place.
alt="">
The next step was to find a good way to mount the heatsinks onto my canopy. I surveyed the inside of my canopy and the best place I could find was in the front corners of the canopy, with the LEDs pointing towards the middle of the tank. I went to Lowe's to see what I could find in the way of metal straps and brackets and found what I thought was the perfect piece - it was in the construction hardware section and was and was a 45 degree angle bracket. The only problem is that they're not stainless steel, so I'll just have to keep an eye on them. I just drilled holes into the heatsink as well as the bracket and screwed them in with metal screws.
alt="">
alt="">
And pics below after mounting the spotlights to the canopy.
alt="">
alt="">
And finally, I ran some 2-conductor wire from one spotlight to the other, wiring them in parallel to the Buck Puck. I braced myself as I plugged the power supply cord into the wall - and they work!!!
alt="">
I made the video below in case you're curious what the shimmer looks like with the LEDs. Please ignore the colors as I completely forgot to set my videocamera's white balance before recording. The actinics, specifically, look nasty.
http://www.youtube.com/watch?v=TVUfIatAXoE
Epilogue:
Power Consumption : With my MH setup, my power consumption for lights alone was ~758w (2x250w M80s which when driving Phoenix 14000K DEs, pull closer to 325w each per Sanjay's data, plus 2x54w actinic T5s). With the new T5 setup and LED supplementation, my power consumption is now down to ~443w (4x54w T5s overdriven to ~80w each, 2x54w actinic T5s, and I calculate each LED driven with 700mA at 3.7v forward voltage drop to consume 2.6w each). So that's a savings of ~315w with the T5 + LED setup, and I've got shimmer !
Still to do - find some way to protect the LEDs and solder joints from salt creep, etc. I think I can use a sheet of acrylic and use spacers to mount them onto the heatsink.
I also decided not to use the fans that came with the heatsinks. Mounted in the canopy, the heatsinks are right next to my canopy fans blowing in, and looks like they should get some good ventilation..
After about 24 hours with the LEDs, here's what I've learned so far:
- as is to be expected (and can be seen in the video), the shimmer diminishes pretty significantly as the T5s get brighter, but still very noticeable even when the daylights are on. These LEDs produce a ton of light! And the clustering helps as well.
- I used all Cool White LEDs in this project. I wonder how the lighting will look (and how the shimmer will be affected) if I throw a Blue light in there? Lumen output of the blue drops to 1/3 that of the white, but I might have to try that out sometime.
- using no lenses, I feel like the light from the LEDs isn't focused enough, but with the 25 degree optics I got, I feel like the light is too narrow. I might try the wider or even the oval lenses to see how they work.
- after being on for 10 hours - the heatsinks are barely warm to the touch, which probably means I can drive them with a 1000mA Buck Puck and get more light without worrying about the LEDs overheating.
I'll post more info as I spend more time with these things!
Enjoy!
In April of 2008, the PowerBrite LED fixtures had just come out, and I bought one to see how well they worked. They did work, as long as the T5s weren't too bright. They worked great when only my Actinics were on, for example, but once the daylight T5s were on, they were pretty much washed out and the shimmer was not noticeable. The lessons I learned from that trial were that the 1w LEDs (60 lumens each) included in the Powerbrites weren't bright enough to overcome the brightness of my overdriven daylight T5s, and that the LEDs were spread apart too much. The LEDs were spaced roughly 3" apart on the 1' long fixture. I think the lights would've been more effective (as shimmer supplementation) if the LEDs were clustered together.
Fast forward to present day - more and more high-power LEDs have been coming out lately, so I thought it was perhaps a good time to give LEDs another try to supplement T5s for shimmer. I would love to get rid of my MHs and move back to T5s. This is my build thread. Maybe we can have more of this type of project in the club!
The OP of the RC thread used the Cree Q5 XR-E LEDs, and those are what I used as well. These LEDs produce roughly 200 lumens when driven at 700mA, which is what I decided to do. These LEDs can be driven up to 1000mA and get more light, but will also generate more heat. At 200 lumens, this is 3x the lumens each of the Powerbrite LEDs generate, and with the tight clustering I was planning, I estimated that I'd have enough light for a good shimmer. My plan was to build two LED clusters - each cluster with 3 LEDs mounted on a CPU heatsink forming an LED "spotlight", if you will.
My Bill of Materials is as follows:
6 x Cree Q5 XR-E Soft White LEDs premounted on Starboards (~$54 total from ledsupply.com)
1 x 3023-D-N-700 Wired BuckPuck LED Driver (~$15 total from ledsupply.com)
6 x 25 degree "narrow" lenses and lens holders (~$9 total from ledsupply.com)
2 x Thermaltake CPU Heatsink with fan (~$25 total from Fry's)
2 x 6-32 drill bit and tap set (~$10 total from Lowe's - I had to get a second one because I broke the first one
)20ft 16ga stranded Primary Wire (~$5 from Lowe's) - only used a few feet's worth
1 x 18.5v DC 2.7A power supply (using an old Compaq Laptop charger)
Other hardware items (6-32 stainless steel machine screws, nylon washers, thermal paste, etc) I already had in my toolbox.
Here is the CPU heatsink I went with. I went over to Fry's looking for CPU heatsinks that had a good-sized flat surface to mount the LEDs and that also came with an 80mm fan. The one below fit the bill perfectly, and even better, there were two "open box" items so I saved another 65 cents or so on each!
This particular heatsink had a copper base to enhance heat transfer from a CPU die, but I didn't need that. Plus, the copper base made the effective size of the heatsink smaller, so I just took it off, giving me a nice-sized flat piece of aluminum for the LEDs. I estimate I can fit 5 of the LED stars comfortably on the face of the heatsink.
Using the LED starboards as guides, I marked off the locations of the screws, then took the heatsinks to work to drill the holes. One of the labs at work has a nice drill press that made drilling the holes a breeze! I then tapped the threads using a 6-32 tap set purchased at Lowe's. I ended up going through two taps. :-/ I broke one as I guess I was rushing it. Take it slowly, and stop and lubricate with 3-in-1 when you feel pressure while turning the tap. The taps will break easily from the torque if you force it.
Even though my plan was to use 3 of the LEDs on each heatsink, I decided to go ahead and drill holes for 5 LEDs for possible future expansion. The picture below is of the 3 LEDs mounted on the heatsink. The pair of holes in the middle of the LEDs are for future expansion of a blue LED. I thought in the future, I could mount a blue LED there for moonlights. The pair of holes in the lower right is for a 4th white LED, in the event the 3 LEDs aren't bright enough. I applied a small amount of thermal paste underneath the starboard then used 6-32 machine screws with nylon washers to mount the LEDs. The nylon washers are very important as the heads of the screws can come in contact with the soldering pads on the starboards, causing a short-circuit.
I used 6-32 machine screws because that's what the majority of the folks on the RC thread used. Some used 8-32 screws which are bigger. The problem I ran into with the 6-32 screws is that the screws were too big to fit completely into the screw slots cut into the LED starboards. This wouldn't have been a problem if I had just spaced the holes slightly further apart, but it was too late and I had already drilled the holes. I ended up grinding the screw slots slightly bigger with my Dremel to allow the screws to go in all the way. One could use smaller screws, but I think anything smaller than a 6-32 machine screw will be harder to find at your local Lowe's or Home Depot.
A quick note on the power budgeting - I decided to use 3 LEDs for each cluster (6 total) mainly because the LED driver I'm using (Buck Puck) can drive up to 6 of the Cree LEDs. Going with 3 each (6 total) allowed me to use just one Buck Puck and keep my costs down. If I found that the 3 LEDs weren't bright enough and had to go with a 4th or 5th LED per cluster, I'd have to get a second Buck Puck to drive the additional LEDs. But before I go to a 4th or 5th LED, I'll probably try driving the LEDs with 1000mA as opposed to the 700mA I'm using the first time around.
As for the Compaq laptop charger that I'm using as a power supply - as I mentioned earlier, it outputs 18.5v DC and 2.7A. Each Buck Puck can drive up to 6 of the Cree LEDs wired in series, but in order to do this, you need a 24v DC power supply (each LED has a forward voltage drop of 3.5v at 700mA which means 6 x 3.5v = 21v, plus 2-3 volts per the mfr guidelines). Fortunately, with my setup, I will be wiring the LEDs in each cluster in series, then wire each cluster to the Buck Puck in parallel. With this setup, both clusters can be driven by the same Buck Puck. Also with this configuration, I just need the power supply to output 3 x 3.5v = 10.5v, so I was able to avoid buying a power supply and save ~$30.
In looking around the house for power adapters, etc. I noticed that laptop chargers and printer power supplies are great power supplies for driving LEDs. They all pretty much output ~18v DC and >2A which is perfect for powering LEDs.
Here are the LEDs in one cluster all wired-up! As mentioned above, I wired the LEDs in series. Each of the clusters will then be wired in parallel to the Buck Puck.
A quick note on soldering - you can do it at least a couple ways that I can think of. You could either solder the wires with the LEDs off the heatsink, or solder the wires with LEDs already mounted on the heatsink. I chose to do the latter because it would be easier to get the wire lengths right, and solder the LEDs in the right positions. If you do the former and solder the wires before the LEDs are mounted, you might have to tweak/bend the wires a little bit to get the LEDs aligned with the screw holes. Doing this would put stress on the soldering pads on the starboards and could break them.
The problem with doing the soldering with the LEDs already on the heatsink, is the heatsink sucks all the heat from the soldering iron, making it tougher to get a nice, clean solder joint. My 25w pencil soldering iron didn't work too well (couldn't get hot enough with the heatsink sucking all the heat out), and I had better results with my 100w soldering gun.
The picture above also shows the lenses mounted on two of the LEDs. I wasn't sure if I was going to use the optics, but I went ahead and ordered them as they were fairly inexpensive. The lenses I ordered are 25 degree optics. The lenses snap into lens holders, and the lens holders have to be somehow mounted to the starboard. I used superglue to attach the lens holders to the starboard. I ended up having to mod the lens holders themselves because there wasn't enough clearance under the holder for the solder joint. I pulled my Dremel one more time to grind the underside of the holders. The pic below shows the underside of the holders - the one on the left is unmodified; the one on the right has been ground out a bit.
I then repeated the process above a second time for the other cluster to make two LED spotlights. I laid out the LEDs in mirror images to each other as both clusters will be on either end of the tank, pointing inwards.
In my tests, the Buck Puck never seemed to generate very much heat, so having it attached to a heatsink wasn't important, but just affixing it to one of the heatsinks seemed like a simple way to do it. I just used some superglue to secure it in place.
The next step was to find a good way to mount the heatsinks onto my canopy. I surveyed the inside of my canopy and the best place I could find was in the front corners of the canopy, with the LEDs pointing towards the middle of the tank. I went to Lowe's to see what I could find in the way of metal straps and brackets and found what I thought was the perfect piece - it was in the construction hardware section and was and was a 45 degree angle bracket. The only problem is that they're not stainless steel, so I'll just have to keep an eye on them. I just drilled holes into the heatsink as well as the bracket and screwed them in with metal screws.
And pics below after mounting the spotlights to the canopy.
And finally, I ran some 2-conductor wire from one spotlight to the other, wiring them in parallel to the Buck Puck. I braced myself as I plugged the power supply cord into the wall - and they work!!!
I made the video below in case you're curious what the shimmer looks like with the LEDs. Please ignore the colors as I completely forgot to set my videocamera's white balance before recording. The actinics, specifically, look nasty.
http://www.youtube.com/watch?v=TVUfIatAXoE
Epilogue:
Power Consumption : With my MH setup, my power consumption for lights alone was ~758w (2x250w M80s which when driving Phoenix 14000K DEs, pull closer to 325w each per Sanjay's data, plus 2x54w actinic T5s). With the new T5 setup and LED supplementation, my power consumption is now down to ~443w (4x54w T5s overdriven to ~80w each, 2x54w actinic T5s, and I calculate each LED driven with 700mA at 3.7v forward voltage drop to consume 2.6w each). So that's a savings of ~315w with the T5 + LED setup, and I've got shimmer !
Still to do - find some way to protect the LEDs and solder joints from salt creep, etc. I think I can use a sheet of acrylic and use spacers to mount them onto the heatsink.
I also decided not to use the fans that came with the heatsinks. Mounted in the canopy, the heatsinks are right next to my canopy fans blowing in, and looks like they should get some good ventilation..
After about 24 hours with the LEDs, here's what I've learned so far:
- as is to be expected (and can be seen in the video), the shimmer diminishes pretty significantly as the T5s get brighter, but still very noticeable even when the daylights are on. These LEDs produce a ton of light! And the clustering helps as well.
- I used all Cool White LEDs in this project. I wonder how the lighting will look (and how the shimmer will be affected) if I throw a Blue light in there? Lumen output of the blue drops to 1/3 that of the white, but I might have to try that out sometime.
- using no lenses, I feel like the light from the LEDs isn't focused enough, but with the 25 degree optics I got, I feel like the light is too narrow. I might try the wider or even the oval lenses to see how they work.
- after being on for 10 hours - the heatsinks are barely warm to the touch, which probably means I can drive them with a 1000mA Buck Puck and get more light without worrying about the LEDs overheating.
I'll post more info as I spend more time with these things!
Enjoy!