DIY led light advice needed

[Highside]

Looking at building a diy led light setup. Listing a few items i am considering and just hoping for some input.


Heatsink: Makersled designer 12"
Cool White led either: Cree XML or luxeon es
royal blues: cree xt-e or luxeon es
true violet 430nm
Drivers, not sure yet hoping for advise

These will be going over a 20gal softie reef so im not sure how much of each to use but I know that i prefer a little bit of a bluer look. Also unsure about the drivers, can I use any size driver as long as I use less leds that the maximum wattage?

 

[revsgirl]

:bump2:

 

[ifarmer]

From my past DIY experience. for softies only. I would suggest buying one of those cheap (on ebay) dimmable led. they are great price and looks a lot nicer than DIY.
The DIY never look nice and the wiring is always messy.
if you have a more sophisticate tank and want to have your own color selection then go with DIY.

 

[Mcreefer]

I'm a fan of mean well drivers. Also of CREE LEDs. You need to read the specs of the LEDs, look for the current and forward current. Your driver for that channel will need to have more mA or amps the the combined total of these numbers.

Here is the best link I could find for you

http://sva.ti.com/assets/en/appnotes/National_LED_White_Paper.pdf

 

[nkd5024]

Both the Cree and Luxeon leds are good quality leds. The only issue I see is that the Cree XM-Ls are 10watts leds where as the XT-E royal blues are 5watts and the 420 violets are 3W. Because of this you'll likely have to use three different drivers or waste a lot of the potential light outlet of the higher wattage bulbs. You could just go with all 3watt bulb as you mentioned that this led build was for soft corals only.

It is also important to decide ahead of time if you want dimmable drivers as well as how many channels you'd like to dim. I recently build my brother an led fixture for his 24gal nanocube with 12x 5W cree xt-e royal blue leds and 12 xp-g cool whites. He added manual dimming to his build with a blue channel and a white channel. My brother has a few sps with his LPS and zoas in his tank and usually don't keep his lights higher than 50% so you could easily downgrade to 3W leds or use maybe around 18 leds instead.

If you want a simple build I would recommend using the Meanwell ELN-60-48P for dimming and one of the Meanwell LPC series for non-dimmable.

I would also recommend throwing in a red and a cyan led for a little extra color.

Have fun!

 

[ccampbell]

I've always done around 40% deep blue, 40% white (cool white), 20% other (Cyan, true violet, red)...

 

[Daimyo68]

The Cree XML are designed to run at 3 different levels:
2.9vF @ .700mA (2.03 watts)
3.1vF @ 1500mA (4.6 watts)
3.35vF @ 3000mA (10.05 watts)
---in my opinion, overdriving will possibly shortening the lifespan, as well as generate more heat. In this case, I would just look for an LED that normally runs at a higher voltage/amperage.

SO, lets say for example, you want to have 15 White XML's, running at the basic 2.9vF @ .700mA. To figure out the driver, you need to do a little math.

Voltage first - You need to take the total number of LED's, and add their voltage together - 15 Cree XML White LED's x 2.9vF = 43.5 volts. Now you know that you need a driver that can supply 43.5v minimum.

The next part is the Current, which will be .700mA (This number does not need to be added like the voltage was, it will stay the same across all the LED's in the circuit).

The last part is Wattage. To figure out wattage you take the individual led numbers, (2.9v x .700mA = 2.03watts) x 15 LED's = 30.45 watts total. Now you know that you will need a driver that can supply atleast 30.45 Watts.

So again, you need a driver that supplies atleast: 43.5v, .700mA constant, and a wattage of atleast 30.45W

If your not confused, keep reading. If your confused, read it again, or just ask any questions :)


Now lets look at drivers. I'll list a couple here since you did not mention if you wanted to dim them or now.

Non-Dimming: Meanwell LPC-35-700. This driver is rated to supply between 9-48v, a constant .700mA, and up to 35Watts
- The Voltage. The driver is self regulating and will supply a minimum of 9v and up to a maximum of 48v. This will meet your needed voltage of 43.5v, the driver will "sense" the needed voltage and self-adjust to the demand.
- The Amperage, .700mA, remains constant
- The Wattage (35 watts), is more than ample to supply the circuit. Again, this will self adjust depending on demand. The example circuit above needs atleast 30.45watts

Dimming Driver: Meanwell ELN-60-48D or ELN-60-48P. These drivers have dimming capability, AND Voltage and Current can be adjusted manually. They are identical except for the way they are dimmed (more on this below). This is the most widely used driver (IMO) due to it's versatility, and can be used in almost every build.
- The Voltage - The driver is self regulating and will supply a minimum of 24v and up to a maximum of 48v (under normal operation. More on this below)
- The Amperage is adjustable, and can supply up to a maximum of 1300mA (More on this below).
- The Wattage (62.5 watts), is more than enough to supply the circuit, and will self adjust depending on demand. (This is double of what the circuit calls for, but as mentioned, it will self adjust under normal circumstances).

OK, so far so good? Time for "More on this below".

ELN-xx-xxD is dimmed via an external Voltage source, that supplies 0-10vDC on a dedicated circuit to the driver. This voltage usually goes through a potentiometer, or is supplied by a reef controller (Apex). The potentiometer, along with an external 10v power supply (usually a wall charger of some type), will adjust from 0-10v when turning the potentiometer. So lets say you have the potentiometer set at 5v. The LED's will recieve less current, hence the will be dimmer than if it was at 10v.

ELN-xx-xxP is dimmed via a Digital Pulse Width Modulation (PWM). Again, this is 0-10v, but the dimming is done by rapidly turning the LED on and off using a duty cycle (like the Reef Keeper Elite supplies). We don't actually see the LED turning on and off, as it happens faster than the eye can percieve it. There are kits that can supply this type of signal.

Adjustable Current - The ELN series of drivers are current adjustable. What this means is that you can adjust the current by opening the driver, and turning the internal potentiometer to the desired amperage needed. In the example above, you need .700mA, so you would adjust the driver to meet this number. There are a couple videos on youtube demonstrating how to do this: Adjusting the ELN 60 48D 0001 - YouTube

Hope this helps. It can be really confusing, as I once found out. But, once you understand Voltage/Current/Wattage, it's pretty easy, and will only take minutes to figure out what you need.

Ask questions, and then ask more questions :)