Not if you can crank up your 48V supply to 56V. The LDD-H is rated to output up to 52V. Even then, chances are good that the Vf of your leds will be less than 3.7V on average. I'd say give it a try. The worst that could happen is- The leds don't light up, and you'd have to remove 1 from the string.
Meanwell LDD driver: for those who want to dim to 0 using Arduino
- Thread starter pwreef
- Start date
Not if you can crank up your 48V supply to 56V. The LDD-H is rated to output up to 52V. Even then, chances are good that the Vf of your leds will be less than 3.7V on average. I'd say give it a try. The worst that could happen is- The leds don't light up, and you'd have to remove 1 from the string.
nemosworld
Active member
if I were you I would look into Phillips luxeon es leds vs the bridgelux.
I have a fixture built with all bridgelux leds and Chinese drivers, while they do grow everything in my tank, I must say they are not that efficient, they also require more voltage than most leds out (cree, Phillips etc) and produce less light. they are only a dollar more each.
the vf is 2.50v @700ma with a max current of 1000ma
joshlawless
New member
Check out the Luxeon ES emitters -- they tend to have a bit lower forward voltages (and can be driven at 1 Amp, unlike the Bridgelux).
--- whoops, didn't see that the posts continued on the next page, and that Felix already beat me to this recommendation.
--- whoops, didn't see that the posts continued on the next page, and that Felix already beat me to this recommendation.
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joshlawless
New member
Is there a downside to doing this? I assume that it might have a negative impact on the efficiency of the PSU, and I'm almost certain it will increase its heat output. Is that about right?
Sacohen
New member
I'm looking at them now on Steve's LED.
They don't seem to have the Violet and Ultra Violet or Pink, but someone said to stay away from the pink.
Their whites are not 10K and 6500, but I'm sure they have something similar.
12 = Blue
12 = Royal Blue
6 = 10K (Warm White)
6 = 6500 (Cool White)
8 = Violet
6 = Ultra Violet
6 = Green
6 = Cyan
6 = Pink
4 = Red
Thanks for the help.
joshlawless
New member
Steve's has indigo (they call them "hyper violet" and "true violet") emitters, just not in the Luxeon ES line. They're located on the "generic" LED page: http://shop.stevesleds.com/Generic-3-Watt-LEDs_c26.htm.
I call them indigo, since they're around 420nm, which is between blue and violet. I bought my violet emitters (405nm Exotics) from a site which I'm apparently not allowed to post here. Hint: they're one of two online vendors carrying MakersLED heat sinks, and they're not ledsupply.com (and didn't try to upcharge me on shipping costs for MakersLED heat sinks after checkout like ledsupply.com did).
I call them indigo, since they're around 420nm, which is between blue and violet. I bought my violet emitters (405nm Exotics) from a site which I'm apparently not allowed to post here. Hint: they're one of two online vendors carrying MakersLED heat sinks, and they're not ledsupply.com (and didn't try to upcharge me on shipping costs for MakersLED heat sinks after checkout like ledsupply.com did).
joshlawless
New member
You've got your color temperatures backwards -- lower Kelvin numbers are warmer whites. 2700K is warm white, 5000K is neutral, 6500K is cool, and 10000K (or 10KK, I guess?) would be very cool white indeed.
I opted for a mix of neutral (5000K) and warm (2700K) white emitters, and let the royal blue and cool blue emitters do the heavy lifting in the blue end of the spectrum, rather than combining cool (i.e., blue-heavy) white lights with blues.
Of course, I haven't put them together yet, so I can't vouch for how it will all look. Still waiting on those heat sinks.
No real downside- The higher output voltage = slightly lower current capacity. Maximum wattage remains the same.
mr.wilson
.Registered Member
I'm having difficulty running two LDD-1000H drivers in parallel with the 4 up board with pull downs. I tried installing IN4004 diodes on the V out + & V out -, but still no light.
When I run the ch1 LDD-1000H, the ch2 LDD-100H puts out 48v (not connected to LEDs). When I do the reverse, the ch1 driver puts out 0v while under no load (no LEDs connected).
I'm using a PWM controller with the pull downs installed. I have tested without pull downs and it still won't light up.
I'm running ch3 & ch4 independently with no issues. Am I missing something???
When I run the ch1 LDD-1000H, the ch2 LDD-100H puts out 48v (not connected to LEDs). When I do the reverse, the ch1 driver puts out 0v while under no load (no LEDs connected).
I'm using a PWM controller with the pull downs installed. I have tested without pull downs and it still won't light up.
I'm running ch3 & ch4 independently with no issues. Am I missing something???
I did some experiments with parallel driving the LDD's earlier in this thread. To the best of my knowledge- I don't think it's feasible in the long run. Others may have different experiences, but from what I saw, one LDD of the pair carried the entire current load, confirming what you're seeing now. The current did double when wired as described, but I discontinued the experiment for fear of damaging the LDD's. Maybe somebody "out there" has figured out how to do it correctly?
aaronpentz
New member
Ive got a few questions.
Let me tell you about my setup or what Im trying to do and maybe you guys can help.
My tank is 72 x 12 x 18. I plan on buying 3 18" makersled heatsinks. I already have one.
I planned on having 6 NW XT-E, 12 RB XT-E, 6 TV, and 2 OCW per sink and would like at least 4 channels of control. I also wanted to build the fixtures so that i could separate them easily and sell them off or re-purpose them on other tanks. I wanted separate driver boards and such.
Question 1) Power supply size selection
Per previous posts Ive seen two ways to size your power supply.
Question 2) Voltage for driver selection
I had planned on using the Cree XT-E lights.
Now the above I think I understand, the question I have about driver selection and power supply voltage selection is. Per the math above I need a 48vdc supply. I am also expecting the drivers on three of the channels to regulate more then half the power. I know they will run less efficiently and warmer. Or would it be better to split my RB channel onto two 700ma drivers making all the channels around 18 volts. Doing that I could get away with a 24 vdc supply properly sized and the ability to use the less expensive and smaller form factor LDD-L drivers.
Ive also got a favor for the people that can develop circuit boards. I can get pretty much anything you want laser cut I work for an OEM CNC Laser Cutting Machine Manufacturer. I would be willing to trade my services and material for your design capabilities. Id like a custom board designed.
Let me tell you about my setup or what Im trying to do and maybe you guys can help.
My tank is 72 x 12 x 18. I plan on buying 3 18" makersled heatsinks. I already have one.
I planned on having 6 NW XT-E, 12 RB XT-E, 6 TV, and 2 OCW per sink and would like at least 4 channels of control. I also wanted to build the fixtures so that i could separate them easily and sell them off or re-purpose them on other tanks. I wanted separate driver boards and such.
Question 1) Power supply size selection
Per previous posts Ive seen two ways to size your power supply.
a) qty x watts x current
So 6 wht @ 1000ma = 18 watts, 12 RB @ 1000ma = 36 watts, 2 OCW @ 500 = watts, and 6 TV @ 500 = 9 watts. 18+36+9+9= 72 watts per fixture or 216 watts for all three. That puts me at a 250 watt supply.
So 6 wht @ 1000ma = 18 watts, 12 RB @ 1000ma = 36 watts, 2 OCW @ 500 = watts, and 6 TV @ 500 = 9 watts. 18+36+9+9= 72 watts per fixture or 216 watts for all three. That puts me at a 250 watt supply.
b) current rating greater then the total output of your drivers
So 3 amps per fixture or 9 amps total That puts me at a 10 amp supply.
So 3 amps per fixture or 9 amps total That puts me at a 10 amp supply.
Question 2) Voltage for driver selection
I had planned on using the Cree XT-E lights.
NW vf 3.0 @ 700ma 3 x 6 = 18 volts
RB vf 3.0 @ 700ma 3 x 12 = 36 volts
TV vf 3.0 @ 700ma 3 x 6 = 18 volts
OCW vf 8.6 @ 500ma 8.6 x 2 = 17.2 volts
RB vf 3.0 @ 700ma 3 x 12 = 36 volts
TV vf 3.0 @ 700ma 3 x 6 = 18 volts
OCW vf 8.6 @ 500ma 8.6 x 2 = 17.2 volts
Now the above I think I understand, the question I have about driver selection and power supply voltage selection is. Per the math above I need a 48vdc supply. I am also expecting the drivers on three of the channels to regulate more then half the power. I know they will run less efficiently and warmer. Or would it be better to split my RB channel onto two 700ma drivers making all the channels around 18 volts. Doing that I could get away with a 24 vdc supply properly sized and the ability to use the less expensive and smaller form factor LDD-L drivers.
Ive also got a favor for the people that can develop circuit boards. I can get pretty much anything you want laser cut I work for an OEM CNC Laser Cutting Machine Manufacturer. I would be willing to trade my services and material for your design capabilities. Id like a custom board designed.
I have a theory on the subject, but maybe you tried this O2.
AND NOW THE DISCALMER: THIS MAY DESTROY YOUR LEDS, LDDS, AND PSU NOT TO MENTION BURN YOU HOUSE DOWN.
But, based on the way some similar drivers I'm using are configured (sure electronics) parellel might work by running the psu + directly to the led (bypassing the LDD altogether. as I recall the LDD only has one internal diode where as the sure drivers have 3..(the LDD may still need the + connection on the V+ in but run the Psu + directly to the LED rather than from the LDD V+ output) and then runing the led - to the two LDDs V out - with a diode on each of the three connections (though I'm not sure it's needed on the + side (it's on the sure drivers I think to prevent wiring backwards.)
the big unknown is what the current handeling of the LDD internals is. With the drivers I've got they are each limited up to 1.5 amp, so in parrelel 3 amps or more is possible, but the diodes have to be also capable of the current. On the sure electronics driver they are limited to a max of 1.5 amps with two in parrelel but that is due to the diodes if I remember correctly.....
mr.wilson
.Registered Member
Thanks for the input gentleman. Do you think this solution would work with the LDDs?
http://www.maximintegrated.com/app-notes/index.mvp/id/4537
http://www.maximintegrated.com/app-notes/index.mvp/id/4537
Sacohen
New member
I've been experimenting with some 50 watt RGB led's lately, so I drew up this Pcb to work with them. It features 3 LDD-H and has the PWM pull down resistors included. The build files and a parts list are attached.
http://www.reefcentral.com/forums/showthread.php?t=2222702&page=23
O2 what does the RGB board do?
The better question would be is I need a 3 up board for my scenario.
Would this work with regular 3W LED's and the LDD-1000H drivers?
I understand basic electronics, all that I can remember from my high school electronics class about 30 years ago.
I think I remember more electronics then I do High School Spanish.
O2 what does the RGB board do?
The better question would be is I need a 3 up board for my scenario.
Would this work with regular 3W LED's and the LDD-1000H drivers?
I understand basic electronics, all that I can remember from my high school electronics class about 30 years ago.
I think I remember more electronics then I do High School Spanish.
The 3up RGB Pcb works just like any of the other designs posted in this thread. Its 3 channels are just labeled by color, for use with RGB leds, instead of numerically for standard led builds. If you only need 3 channels of LDD's, then that PcB deign will work just fine for you.
nemosworld
Active member
there are 6 up boards just a few pages back.
