Meanwell LDD driver: for those who want to dim to 0 using Arduino

I got my information from a chain of emails with Led Group Buy. On their FAQ sheet, it states a 180W 3.75A PS can power 2 Lumia 5.2's. However, 2 channels need to run at 1000mA and 3 channels at 700mA. That would mean the PS would need at least 4100mA (4.1A) to supply the demand of the 5 drivers if they drew at their rated capacity at all times. So I questioned them how it is possible to provide less amperage from the power supply than the drivers demand. I was told that do not look at amperage when considering power, pay attention to watts. He then continued with the following statement:



From that statement it looks like the amperage of a power supply is not the limiting factor, but the total wattage being pulled from the LED's themselves. So if someone wants to hook up 9 LDD-1000 channels, but only uses 15v per channel, does he need a 9A PS, the answer is no.

Further reinforcement to what I was thinking. Thanks!

--Colin
 
LDD drivers are DC to DC converters and they will regulate their output and vary to input. They will draw less current if there is extra voltage available. So unless you are using Maximum length strings for the input voltage, the current draw from the supply will be less than the rated output current. I in only equals I out if V out equals max V in. Does that make sense?

Krazie;jester:
 
LDD drivers are DC to DC converters and they will regulate their output and vary to input. They will draw less current if there is extra voltage available. So unless you are using Maximum length strings for the input voltage, the current draw from the supply will be less than the rated output current. I in only equals I out if V out equals max V in. Does that make sense?

Krazie;jester:

Yep. Someone had told me otherwise and totally confused me. I'm aware of Ohm's law and what I was being told made no sense to me in that context.

Now to figure out some PCB's to mount these suckers on. And find some $$ to buy some stuff. :D

--Colin
 
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Check with O2Surplus. He made a bunch of different LDD driver boards with different configurations. I'm sure he has left overs that he would like to sell. :) Krazie:jester:
 
controlling them with an Arduino is going to be hard. As I understand the Maxwellen dims with a potentiometer and not a PWM signal or a 1-10 signal. I might be wrong but early on when I looked at these that is what I was told.

Are we talking about the Mean Well LDD dimmable? If so, I thought they accepted a PWN signal. Shouldn't be any trouble from Arduino's if so. That is how I'm planning to dim mine anyway using my Reef Angel.
 
I want to control my led's and drivers with my arduino. I Have: Maxwellen Dimmable Constant current LED Driver 7-12 pcs x 3w 36w running 10 x 3w Warm White led's. Maxwellen Dimmable Constant current LED Driver 7-12 pcs x 3w 36w running 8 x 3w Blue led's. Maxwellen Dimmable Constant current LED Driver 12-20 pcs x 3w 60w running 20 x 3w Cool White led's. Maxwellen Dimmable Constant current LED Driver 15-30 pcs x 3w 90w running 30 x 3w Cool White led's. Dimmable Constant current LED Driver 3-5 pcs x 3w 15w running 5 x 3w Red led's. Dimmable Constant current LED Driver 3-5 pcs x 3w 15w running 5 x 3w UV led's. I want to control these with my Arduino Mega 2560 but the power required for each driver is different and higher than the arduino can handle. Wow would I do this?
Wrong thread for what you want, this thread is about Meanwell LDD drivers. If you want Arduino control, you need 5v PWM drivers like the LDD, your drivers are potentiometer control only.
 
"The longer version of that is that an LDD driver that is rated for 1000mA will not pull 1000mA from the power supply at all times, it depends on how much voltage the LEDs will be using. The output of the LDD is ~45v, and if you were running the full 45v of LEDs then you would pull 1A from the power supply, but if you were only pushing 12v of LEDs, then the LDD would take another 3v from the 48v input, and it would convert the remaining 33v into the output current. The 15v total used is around 31.5% of the total voltage (48v), so it will only pull 31.5% of the current, so ~315mA instead of the full 1000mA."
Sorry - too idle to correct the tags properly. The above is the quote you gave from LED group buy. That is sort of a pseudo science explanation, but if it helps people to work it out that way :thumbsup:

Tim
 
Hi, Does anyone have a gerber file of 2 meanwell LDD-H drivers ? can someone share it . i want to add a relay on to it with some changes.
 
Does anyone have a diagram with 2 PSUs hooked up to the LDDS using O2Surplus 8-UP boards. My question is concerning common ground. Would I have the same setup as post#2513 but make sure the ground from both PSUs are tied together?
 
The grounds on the output side of the PSU's are all common just like the ground from a controller needs to be common. Just tie the grounds together and you will be fine. Krazie:jester:
 
Using Mean well LDDXXX-L and H LED Drivers

Using Mean well LDDXXX-L and H LED Drivers

Hello people,

I came across these threads here on Reef Central discussing DIY DC powered dimming using the little Mean Well LDDXXX L and H led driver units.

I wanted to hook up an off the peg DC PWM dimming unit to work with a 12 or 24v dc supply and found just the thing on eBay (of course).
I have hooked up some (correctly matched) LED to the LDDXXX L and / or H units and PWM dimmer and have been working the system using just a straight forward 2 wire system and disregarding the extra PWM input provided with the LDD units. So, that output direct from pwm dimmer direct to input (pos / neg) of LDDXXX units.
The result is just brilliant with almost seamless 0 - 100% dimming. However, despite the system working so brilliantly, I wonder why this method is not mentioned by Mean Well. The system has been operating now for some months without problem and everything runs cool to the touch (dimmer and LDD units).
I would appreciate feedback from anyone who had either done similar or who has any advice or opinion going forward with such.
 
Does anyone know how to test o2surplus 8up boards? I measured power going to the board and the pwm going in...but get zero on the led side..and my leds are not coming on at all
 
Does anyone know how to test o2surplus 8up boards? I measured power going to the board and the pwm going in...but get zero on the led side..and my leds are not coming on at all


Do you have a common ground connection between the 8up PcB and your PWM source?
 
Yep...I have double checked that...I am hooking 1 of the boards up trying to check 1 signal and nothing is showing on the led side...and I am using a typhoon controller
 
I was thinking maybe the driver burned out or something but no smoke

Do you have both positive terminals on the 8up PcB connected to your power supply? I designed that PcB with "Rott" in mind (he needed the ability to power the PcB from two different power supplies) The positive power inputs are isolated from each other and only supply voltage to channels 1-4 or 5-8. Here's a photo of the circuit for reference.

8upLDD-HampDualSCW_zpsabdc6ddb.png
 
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