foxhuntr
Valuable Member
Was thinking about going to LED's on my reef tank and was looking for everybody's input on the best place to by Cree DIY kits...... would love if everybody could help me out....thanks
Led lights
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chadfarmer
profilux in the house
reefledlights.com
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foxhuntr
Valuable Member
ok..... another question......i have a 135g tank.....it has 2 center braces so i need to have 3 fixtures with 48 3 watt leds per fixture....now each partition on the tank measures 21"x14"...what size heatsink should i use.....was thinking about 80 degree lenses on the leds because the fixtures are gonna be about 16 inches above the tank....i am just not sure about how wide of heatsinks to get and still have the coverage....i am gonna run a 2:1 ratio blues/whites....the leds are gonna be 24 XR-E royal blues,12 XR-E cool white and 12 XP-G neutral whites with 65 degree lenses....all i need to know now is how wide of heatsink to get....i think i can go with a heatsink 18" long but how wide and still get the coverage ??? anybody with any idea's ???
wld1783
Well-Known Member
The 8.46 wide by 18" heatsink should work. We should have thoes drilled and tapped next week if needed.
I'm not a fan of dimming with PWM it basically turns the LED on and off really fast to simulate dimming. I'm not sure this is good for the longevity of the LED. Also and more importantly when you dim with PWM you get s slight spectrum shift. The spectrum of our premium LEDs are specifically chosen to bring out the most colour in your corals. The ELN 60-48D or the Inventronics EUC 40S0700DS are the drivers you want they work with the 1-10Vdc output of the APEX
As far as optics I would go with the 70 Degree Cree based on your tank. They also gave us a higher PAR reading than the 60 degree. For the XPG use either the 60 or 80 Degree LEDLink optics
I'm not a fan of dimming with PWM it basically turns the LED on and off really fast to simulate dimming. I'm not sure this is good for the longevity of the LED. Also and more importantly when you dim with PWM you get s slight spectrum shift. The spectrum of our premium LEDs are specifically chosen to bring out the most colour in your corals. The ELN 60-48D or the Inventronics EUC 40S0700DS are the drivers you want they work with the 1-10Vdc output of the APEX
As far as optics I would go with the 70 Degree Cree based on your tank. They also gave us a higher PAR reading than the 60 degree. For the XPG use either the 60 or 80 Degree LEDLink optics
FiReBReTHa
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make sure you get the premium royal blues from bill, makes a difference in corals. check my sig for photos from my 120g tank. check the last page for most recent photos.
CJO
Valuable Member
It doesn't need to be too wide, maybe 8"? Also, you might want to use narrower optics than 80 degrees if you are mounting them 16 inches up. How deep is your tank?
You want the 48d with an Apex.
CJ
You want the 48d with an Apex.
CJ
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foxhuntr
Valuable Member
thanks everyone ......my tank is 24" deep...i was also thinking about going to 70 degree lenses...i dont have my apex just yet....but i do need drivers that i can dail down to acclimate my coral or get the color in the tank i want....would i be able to do this with the ELN60-48D ????
Troylee
all about the diy!!!!!
yup there nice drivers and work extremely well with the apex..... not much to add here you have been given great sound advice from everyone... where to get them, what size etc... i agree with it all...1smile1
FiReBReTHa
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yup, thats what I have.
wld1783
Well-Known Member
Click the bottom video,
Youtube Videos Aquarium Lighting | LED Aquarium Lighting Aquarium Lighting | LED Aquarium Lighting
it shows the newest optics we got in.
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foxhuntr
Valuable Member
ok....then its settled......24 XR-E royal blues with 70 degree optics, 12 XR-E cool whites with 70 degree optics and 12 XP-G neutral whites with 80 degree optics......4 ELN60-48D drivers ....all attached to 1 18"X8.46" heatsinkUSA....2 fans......ALL purchased from Bill at Reef Led Lighting.....new lighting system here i come...thanks everybody
Hahnmeister
Active Member
I was going to add ledgroupbuy.com Great prices on the highest grade LED's.
I got news for ya, with rare exception, almost everything out there is PWM dimming by definition, even drivers w/o dimming. Even if it has an "analog" enable or dimming pin, it is pulsing the output current at the gate. Even if it doesn't dim, most dimming IC's are using some sort of buck, boost, or buck-boost DC/DC conversion that uses a gate with PWM modulation to control the current. The thing is, the pulsing is done in the kHz range, so its not like anything will notice. FWIW, your tube TV's, light bulbs, etc... are all running a 60Hz or derivative of pulsed current (pulsed current vs. AC... not very different when you think about it), and if you cant notice that, then rest assured that kHz is impossible. Your halides, T5HO's, etc. as well. Many "add on" circuits that connect to dimming ballasts are really just PWM generators with that variable PWM signal output for control.
I have also noticed that most of the newer, higher efficiency drivers are going with PWM as the primary dimming function and most are using some sort of high speed PWM as the primary drive control. I have been making my own drivers with the National LM3409HV DC/DC driver (buck) which is the same chip that a guy at RC posted about (from Russia where he made his own PCB Drivers, controller, etc.). Its sort of funny because he said he picked the LM3409HV because it doesn't pulse the output... well, I got news for ya... It does. The clock in the LM3409HV compares the output current to the reference and then puts out the command to raise or lower the output every clock cycle, so the output looks like a sawtooth signal. Granted, the sawtooth "small signal" is small compared to the drive current itself, but its still there. As far as what the LED sees though... thats why they run either a capacitor in parallel with the LED's or a smoothing/choke inductor on the output to the LED's. This smoothes out and averages out the waveform. On the last LM3409HV I just made last night, I used a "huge" 18uH inductor on the output. Thats enough to smooth out just about any pulsed signal to the steady state.
My personal opinion is that every reef LED build should use an external AC/DC switch-mode converter. I use the Meanwell HRPG-450 and HRPG-300. These are very high efficiency power supplies that supply 24VDC power up to very high current ratings. I stick to 24v or under, since the US Navy considers the highest safe "touch voltage" for water to be 28VDC... higher than that and you could get a shock. So 24VDC is a good maximum, even though in reality you wont be coming into direct contact with the conducting elements anyways.
Then, once you have a variable DC power supply, you can make your own current drivers. In my case, Im using the LM3409HV. This allows me to put about 6-8 LED's on each driver before I hit 24 volts. This allows me to have multiple channels to control as well, each with their own current setting. For a build for say, a 100-120g, I would have something like 20-24 channels of LED's. Then these channels can all be controlled by an Arduino or other microcontroller (or you can simply wire in dials for dimming/on/off control). Overall efficiency on this is something like 97% for the power supply, and something like 94-97% on the drivers (depends on the voltage and current of each channel). The drivers are also small enough to be mounted right on the underside of the heatsink next to the LED's, so less bulk. But the main idea here is that all 120VAC power is kept away from the water in the tank. When I see all these AC drivers stuck right to the top-side of a giant LED fixture, I am reminded how one of the main benefits of LED's has been undone.
The other important thing to note with this setup is the dimming. Having multi-channel controllers supply analog signals has its flaws. By the time you run all the wiring, the distance itself could cause a voltage drop so that you never run your LED's at full power, in particular if you run thinner wires. PWM dimming, OTOH, only has two states to sense... on and off. So you know when you are getting 100% or 50% basaed on timing, not relative voltage levels. If I were to use these drivers with analog dimming, I would be converting the PWM output of the controller to analog, adding a few op-amps or an IC at least. Then I would be adding the exact opposite circuit at the other end to convert the analog signal to PWM to get fed to the IC's enable pin. Both of these extra circuits would then have to be configured, tested, etc. Both of these circuits would add extra components that would lower the reliability and also end up consuming more power. With PWM, I dont even have to adjust anything. Once the controller is programmed to make whatever PWM waveform, and the voltages/currents are compatible, it just needs to be hooked up. Thats all. You know it will work, and you know that if you put 50% into the controller, the LED's will be at 50%. That reminds me, most analog dimming is non-linear as well. Some "analog dial conversions" use a signal generator (triangle wave), a DC level adjustment, and then output a PWM signal. The only problem is that lets say you turn the dial to dim 10%... it might just be 5% at first. Then you go down another 20%, but instead of a 10% drop, you get a total 35% drop. The reasons vary... sometimes the PWM waveforms aren't perfect. Sometimes the analog voltage control isn't linear either. If you use just analog dials to adjust the dimming that dont even use a PWM generator (as in, a pure analog dimming pin input), then you really dont know what you are going to get. This is why most of the industry is/has moved to PWM dimming. That way, when you tell your backlit TV to dim from 100% at a 10 setting, the 9 setting is 90%, not 60%, and then the 8 setting is 80%, not 50%. PWM dimming is alot better for the industry, and its alot better for the hobbyist as well, believe it or not. I think most people just dont like it because they dont understand how it works, what it stands for, or how to use it. Its actually pretty simple. With use of a microcontroller, its just some software programming and presto, you have a dimmer that can control an unlimited number of channels and serve as a clock/timer as well.
I got news for ya, with rare exception, almost everything out there is PWM dimming by definition, even drivers w/o dimming. Even if it has an "analog" enable or dimming pin, it is pulsing the output current at the gate. Even if it doesn't dim, most dimming IC's are using some sort of buck, boost, or buck-boost DC/DC conversion that uses a gate with PWM modulation to control the current. The thing is, the pulsing is done in the kHz range, so its not like anything will notice. FWIW, your tube TV's, light bulbs, etc... are all running a 60Hz or derivative of pulsed current (pulsed current vs. AC... not very different when you think about it), and if you cant notice that, then rest assured that kHz is impossible. Your halides, T5HO's, etc. as well. Many "add on" circuits that connect to dimming ballasts are really just PWM generators with that variable PWM signal output for control.
I have also noticed that most of the newer, higher efficiency drivers are going with PWM as the primary dimming function and most are using some sort of high speed PWM as the primary drive control. I have been making my own drivers with the National LM3409HV DC/DC driver (buck) which is the same chip that a guy at RC posted about (from Russia where he made his own PCB Drivers, controller, etc.). Its sort of funny because he said he picked the LM3409HV because it doesn't pulse the output... well, I got news for ya... It does. The clock in the LM3409HV compares the output current to the reference and then puts out the command to raise or lower the output every clock cycle, so the output looks like a sawtooth signal. Granted, the sawtooth "small signal" is small compared to the drive current itself, but its still there. As far as what the LED sees though... thats why they run either a capacitor in parallel with the LED's or a smoothing/choke inductor on the output to the LED's. This smoothes out and averages out the waveform. On the last LM3409HV I just made last night, I used a "huge" 18uH inductor on the output. Thats enough to smooth out just about any pulsed signal to the steady state.
My personal opinion is that every reef LED build should use an external AC/DC switch-mode converter. I use the Meanwell HRPG-450 and HRPG-300. These are very high efficiency power supplies that supply 24VDC power up to very high current ratings. I stick to 24v or under, since the US Navy considers the highest safe "touch voltage" for water to be 28VDC... higher than that and you could get a shock. So 24VDC is a good maximum, even though in reality you wont be coming into direct contact with the conducting elements anyways.
Then, once you have a variable DC power supply, you can make your own current drivers. In my case, Im using the LM3409HV. This allows me to put about 6-8 LED's on each driver before I hit 24 volts. This allows me to have multiple channels to control as well, each with their own current setting. For a build for say, a 100-120g, I would have something like 20-24 channels of LED's. Then these channels can all be controlled by an Arduino or other microcontroller (or you can simply wire in dials for dimming/on/off control). Overall efficiency on this is something like 97% for the power supply, and something like 94-97% on the drivers (depends on the voltage and current of each channel). The drivers are also small enough to be mounted right on the underside of the heatsink next to the LED's, so less bulk. But the main idea here is that all 120VAC power is kept away from the water in the tank. When I see all these AC drivers stuck right to the top-side of a giant LED fixture, I am reminded how one of the main benefits of LED's has been undone.
The other important thing to note with this setup is the dimming. Having multi-channel controllers supply analog signals has its flaws. By the time you run all the wiring, the distance itself could cause a voltage drop so that you never run your LED's at full power, in particular if you run thinner wires. PWM dimming, OTOH, only has two states to sense... on and off. So you know when you are getting 100% or 50% basaed on timing, not relative voltage levels. If I were to use these drivers with analog dimming, I would be converting the PWM output of the controller to analog, adding a few op-amps or an IC at least. Then I would be adding the exact opposite circuit at the other end to convert the analog signal to PWM to get fed to the IC's enable pin. Both of these extra circuits would then have to be configured, tested, etc. Both of these circuits would add extra components that would lower the reliability and also end up consuming more power. With PWM, I dont even have to adjust anything. Once the controller is programmed to make whatever PWM waveform, and the voltages/currents are compatible, it just needs to be hooked up. Thats all. You know it will work, and you know that if you put 50% into the controller, the LED's will be at 50%. That reminds me, most analog dimming is non-linear as well. Some "analog dial conversions" use a signal generator (triangle wave), a DC level adjustment, and then output a PWM signal. The only problem is that lets say you turn the dial to dim 10%... it might just be 5% at first. Then you go down another 20%, but instead of a 10% drop, you get a total 35% drop. The reasons vary... sometimes the PWM waveforms aren't perfect. Sometimes the analog voltage control isn't linear either. If you use just analog dials to adjust the dimming that dont even use a PWM generator (as in, a pure analog dimming pin input), then you really dont know what you are going to get. This is why most of the industry is/has moved to PWM dimming. That way, when you tell your backlit TV to dim from 100% at a 10 setting, the 9 setting is 90%, not 60%, and then the 8 setting is 80%, not 50%. PWM dimming is alot better for the industry, and its alot better for the hobbyist as well, believe it or not. I think most people just dont like it because they dont understand how it works, what it stands for, or how to use it. Its actually pretty simple. With use of a microcontroller, its just some software programming and presto, you have a dimmer that can control an unlimited number of channels and serve as a clock/timer as well.
Last edited:
Glenn
Reefer and Model Railroad
are you going to have the Apex by the time you're ready to build/use the LEDs? If not, you'll have to find a 10v power supply (or close to it), otherwise the LEDs won't light up at all. A 9v battery would work. Or if you want dimmer LEDs, some combination of AA or AAA batteries (four would give you 6v) would also work.
wld1783
Well-Known Member
Hahnmeister
Wow
There is at least 100 ways of doing LEDs right and well over 1000 ways of doing them wrong.
Personally I'm not sold on PWM due to the spectrum shift. Many including your self have had good results using an Arduino or other microcontroller. I looked int these options and fully understand your point.
However I'm curious on why the big three controllers: Apex, Profilux and Reef Keeper do not use PWM or offer a PWM module.
The Drivers we recommend have a linear response to voltage change and are up to 93% efficient. Yes we do have an Inventronics driver which can drive 60 LEDs in series. This is a bit more than the Navys 28Vdc safety standard, but as an Air Force guy I'll leave the Navy to their cold coffee and defer to the NEC and say that a Class II driver like the Mean Well 60-48D at 48Vdc is more than safe for general purpose applications.
Parallel Strings of LEDs do offer advantages in efficiency but also have some draw backs.
"But the main idea here is that all 120VAC power is kept away from the water in the tank. When I see all these AC drivers stuck right to the top-side of a giant LED fixture, I am reminded how one of the main benefits of LED's has been undone."
Our consultation to LFSs have been to keep the AC away from the water. Some of our builds have the drivers 25 Feet away from the LED in a utility room. My APEX is 30 feet away from my office tank and still controls several Mean Well 60-48D and 3 Inventronics EUC-150S070DT with no noticeable difficulty or drop in voltage...Door Bell Wire Used.
I know PWM is one of the 100 ways that works, I'm just still not sold it works best. All things being equal the spectrum shift bothers me as sometimes it may be noticeable.
Cheers
Bill
Hahnmeister
Active Member
Spectrum Shift? I have not experienced this myself. Do you have some more info or a link? What is the frequency range that this would apply to? I tend to stay in the 1kHz range and up so maybe that has something to do with it...???
Wow, Door Bell Wire you say. Thats interesting. I suppose we are talking about currents in the nA range though. One wire with low current is no problem, but if you had to control banks of enable pins with an analog signal, your signal source might not provide enough current. Once we move over to totem-pole/CMOS architecture, now the current required for the dimming input drop a good amount from what I have seen. If you are only doing a few channels on analog, no problem, but having a dozen or so would start to be a problem.
Wow, Door Bell Wire you say. Thats interesting. I suppose we are talking about currents in the nA range though. One wire with low current is no problem, but if you had to control banks of enable pins with an analog signal, your signal source might not provide enough current. Once we move over to totem-pole/CMOS architecture, now the current required for the dimming input drop a good amount from what I have seen. If you are only doing a few channels on analog, no problem, but having a dozen or so would start to be a problem.
wld1783
Well-Known Member
The Carclo Optics and the LEDLink are our two newest additions. The LEDLink only work with the XP-E and XP-G. We plan on having the XR-E version soon but want to do a serious PAR comparison first.
Bill
Bill
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