LDD Drivers, why and how?

[cosmith71]

A thread on Reef Central, which backs up what RapidLED said. Specifically, a posting from someone who had pretty much the same conversation with LEDGroupBuy.com.

Again, basic Ohm's law. Wattage in = Wattage out. Voltage from the power supply is constant, current from the LDD is constant, but voltage varies depending on the number of LED's connected. Therefore, the only other variable is the current from the power supply.

LDD's are DC to DC convertors. Constant voltage in, constant current out.

--Colin

[cosmith71]

Looking at these boards from Coralux.

http://coralux.net/?wpsc-product=ldd-5-driver-board

Seems like a lot less hassle than ordering custom boards like the ones in the RC thread.

--Colin

[lnevo]

One of the led companies (rapid or ledgroupbuy) has a daisy chainable board that is pretty cool. One board gets the power supply input and dimmer rj-45 input (i think) and then you can add boards with drivers. You can set what channel number each driver board uses. They also had a board that you can plug fans into.

[lnevo]

Damn, i cant find it now

[89delta]

Before I got my RA+ I was using a DIY controller from BubbasGuppies. It's 6-channels total and selectable per each driver. The Controller itself offered weather patterns,lighting and moon phases via long/lat. But after figuring out the coding for the RA I just currently use the standard pwm channels for my blues and whites. I have 8x 10,000k whites, 4x 420nm UV and 12x 450nm RB's on my heatsink over my 29BC. But I have no issues running these LDD-L drivers what-so-ever with the 10k resistor grounded on one side and the other on the PWM signal side.

[cosmith71]

I'm starting to think about wiring.

I have two fixtures, each with 4 channels (8 wires). That's 16 wires coming up from the stand to the canopy. I'd like to have each fixture able to disconnect in the canopy as well as a disconnect before the canopy to simplify removing the canopy.

So,

Code: Select all

                                -----8 Wires-----Plug-----Fixture
                                |
Drivers ------16 Wires------Plug-----8 Wires-----Plug-----Fixture

Would D-SUB connectors work? Maybe a 25 pin and 2 15 pins (for future expandability)? I'm not sure how they're rated.

Right now I'm using Molex connectors, which I really don't like.

--Colin

[rimai]

Where are your drivers located? In the stand or canopy?

[cosmith71]

Drivers are in the stand.

[cosmith71]

I suppose it would involve much less wire to have them in the canopy, although I worry about moisture damage.

[rimai]

I think you need heavier gauge than the D-sub cable can provide.
Remember that you could be running up to 1000mA through those wires.

[cosmith71]

That's what I was afraid of.

I'm thinking I could put the drivers on top of the canopy to protect them from moisture and then only have to run the two power wires up. Then figure something out to be able to disconnect the fixtures.

--Colin

[89delta]

I suppose it would involve much less wire to have them in the canopy, although I worry about moisture damage.

Put your drivers in a waterproof enclosure. With my BC29 it was easy since it had the acrylic cover for the lights in place already.

[rimai]

I think I'm going to create a wireless dimmable LED driver

[cosmith71]

I think I'm going to create a wireless dimmable LED driver

You shouldn't tease.

[cosmith71]

I suppose it would involve much less wire to have them in the canopy, although I worry about moisture damage.

Put your drivers in a waterproof enclosure. With my BC29 it was easy since it had the acrylic cover for the lights in place already.

That's a thought. I need to check out Home Depot and see what's available.

I'm also considering just mounting them on top of the canopy. It's almost 7 foot tall so they wouldn't show. I could then just run wires through the top to the fixtures.

Decisions, decisions.

--Colin

[89delta]

Radio shack has an 8*6*4 enclosure for under $10. If you seal the edges n screw holes with a little silicone it'd be water tight. But you'd still want airflow to the drivers to keep them cool. A thought though is you could cut out a hole in the enclosure to mount a heatsink on top and thermal paste the drivers to the heatsink.

Sent from my SAMSUNG-SGH-I717 using Tapatalk

[rimai]

You shouldn't tease.

Not teasing
I'm placing the order for the pcbs tomorrow!!!
All I need now is a few strings of LEDs to test it
I'll see if I can dig something.

[cosmith71]

I have extras from RapidLED I can send if you need some. I just swapped out my cool whites for warm whites.

And details, please.

--Colin

[ReEfnWrX]

I just swapped out my cool whites for warm whites.
--Colin

Warm whites are dangerous.... too much algae loving spectrum... You should switch to Neutral Whites...

[cosmith71]

I just swapped out my cool whites for warm whites.
--Colin

Warm whites are dangerous.... too much algae loving spectrum... You should switch to Neutral Whites...

Sorry, I meant neutral whites. I had cool white + red + green and now just the neutral whites, royal blues, and violet. I took my lenses off as well. I'm digging the look.

At any rate, I have a bunch of cool whites just sitting around.

--Colin

[ReEfnWrX]

You should try the 4:2:1:1 spectrum. RB:NW:CB:UV.. Add maybe 1-2 Green/Red for every 2 square feet and then on a separate channel add some Lime LED's to control the spectrum look of your tank....

One of the nicest LED spectrums I have seen in person. He had great coral growth and color as well

[cosmith71]

CB?

[ReEfnWrX]

I took my lenses off as well. I'm digging the look.
--Colin

Unfortunately LED's have a 120º spread without lenses and will provide awful Par ratings without optics..

CB?

Cool Blue. I think that is around 480nm.

[lnevo]

Thought it was Cyan Blue and should be more like 510nm...

You'll get better blending and less disco without lenses. It all depends on the depth of your tank and how high you have the fixture off the water.

I'm digging the idea of wireless drivers.

[ReEfnWrX]

Cool Blue is the same as Blue give or take 5-10 nm.

[cosmith71]

The tank is 24" deep and the LED's are around 6" up. Even with 80 degree optics I couldn't get enough spread to cover the tank and things near the top were burning. I'm hoping the better spread helps make up for the lower PAR.

--Colin

[ReEfnWrX]

How many LED's do you have? and what size tank do you have LXW?

[cosmith71]

64 LED's right now (room for 72). 120G tank, 48x24x24.

--Colin

[ReEfnWrX]

6" is extremely close to the water for LED's. With 80º optics you should be in the 8"-12" range.

Also 60º optics are recommended for 24" or deeper.

Coral burning at the surface is probably due to the LEDs being so close to the water and maybe not enough acclimation?

See how it goes with no lenses but I Bet you will see minimal growth.

[89delta]

I agree with ReEfnWrX on the height. I ran 2x IT2040's (120W) on my 120 on each side of the cross brace that were 11" from the surface. I started out with my max being 50% and every two weeks went up by 5% to acclimate the corals. My Purple and Red Digi, Bubble Gum Monster and Birds of Paradise were doing great under them. Running no lenses on the LEDs won't do you any good for corals unless under 18" of depth. The default 90 degree optics worked fine. Although since I didn't think about putting in a few fans into the hood the drivers crapped out on me due to overheating after 4mths at 100%. Am running T-5s on it now.