another LED build. question on converter

[FDdragon]

So. Am looking at building my own LED lighting sytem and need some guidance.so i am going to use some 3w LEDs (Blues, whites reds) and i can space them, glue (or screw) and solder them....but i am not sure what i need to use to connect them to a wall outlet. The powet output from the wall is obviosuly more than 3w so i dont want to burn them. I am also planning on havng them dimmable.

What can i use to converter the power?
Im looking at an inexpensive method. (if i am going to buy some expensive piece of equipment i might as well buy a used light system....which defeats my own build)

can i use some 1w bulbs in the mix?

Thanks.

[poakley723]

You have to use what is called a driver.

I have two mean well ELN-60-48D that I got off the forum a few months back that I am not using if you would like them. I could give them to you for $30. These driver will run 8-14 3 watt LEDs each and are dimmable.

I am not sure about mixing 1 watt leds in the mix with 3w LED.

[FDdragon]

Will those be enough to light up a 125 gallon, 22" tall tank with some corals? I have read that it should be around 2-3 watts per gallon...so if i max out at 14 bulbs, 3watts each, thats 42watts per driver. Thats 84 watts.

Thanks for the info. Please let me know if those two will work.

[unbereefable]

First things first. If you're tryin to diy a led fixture to save money, it actually cheaper to buy a used china led fixture. They can be found on the boards pretty cheap. Seen them as low as $80. They can be had new for <$200. And that's for a full spectrum fixture. DIYing isn't really worth it anymore unless you're trying to creat something similar to a high end fixture. One can build something similar to a radion/hydra 52 for usually less than half of what the fixtures retails for. But if you've only got half to start with, reef breeders/reef radiance/ocean revive CAN'T be beat.

If you want to stick with what you have, you've got to do some reaserch. You need to know how to test for shorts, check continuity, and make sure LEDs are properly heatsinked. The hotter LEDs get, the less efficient they are. Which leads to early failure.

You'll needs drivers to run the LEDs. What poakly has will work. And he's giving you a great deal. But with these drivers the voltage is what regulates how many LEDs can be run. It provides a max of 48V. You need to find the forward voltage of each led and add it up till you get to about 44V. You should always leave a little extra room so you don't run the drivers at max. Most aren't 100% effiecient so the can't always handle being run at max. So lets say each led has a forward voltage (Vf) of 3V so 44/3 = 14 LEDs that can safely be run. Higher total Vf = less LEDs.

So if you want 2-3 watts/gal, lets say 2, you want 250 watts total. You'll need 6 of these drivers to run the LEDs to get your 250 watts. Which will give you 84, 3 watt LEDs. The 1 watt LEDs are pretty much useless with the availability of 3 watt LEDs. I'd leave them out and replace them with 3 watt chips.

[FDdragon]

yeah, ive been looking and have seen some good priced systems. The ones I have found are normally around 120w and these guys are using them on large tanks as well.

so just to make sure I understand this...the rule of thumb is around 2w per gallon. is this correct? so if I find some inexpensive 120w full spectrum dimmable lights, I would need two of them to light my tank correct? or will a 120w light work? (ive seen people with 120g+ tanks using only one light that's around 120w and am wondering if this is acceptable)

thanks again.

[unbereefable]

There's no real rule of thumb when it comes to LEDs. Most go by how much light the fixture state they can handle. So for example, a 120 watt china box says it will handle a 60 cube. 24"x24"x24". Which works out to 2 watts/gal. But a single hydra 52 says it can handle a 36x36x24 area. Which is about 134 gallons. And at full blast I think the hydra 52 uses 135 watts. So that's 1 watt/gal. But I'm sure at the very edge corals might struggle as opposed to being directly under the light.

I haven't seen many 120s with one single 120 watt led fixture. If hung high enough, the light will cover the whole tank,but par will be greatly reduced. I think your best bet is to purchase a fixture from the companies I mentioned above. Reef radiance is the cheapest I believe, and they offer a great warranty.

[FDdragon]

ok, so ive been doing a little more research, (just for peace of mind on my end) and trying to understand this whole voltage, watts, ac/dc stuff. When I search online for drivers...what is it exactly that I should be looking for when I am trying to connect 3w (2.4v) bulbs?

-I see the input is 110v, which is my outlet powering the unit. Correct?
-I see the output on the drivers ranging from 12v@10A - 54@2.3A. So I take it that this is how much power the system is drawing from my outlet. is this correct?
-I see Constant Current adjustable via PWM or 1-10VDC Signal. I take it that this is the range of direct current....but after this im lost.

I understand that the watts of the unit are the max that it can deliver.....so a 150w unit can use 50 3w bulbs....or 15 10w bulbs, etc. Where do the 2.4v bulbs come in to play?

As mentioned, i just want to understand this. Thanks guys!

[pigpimpc]

hey can i stop by sometime and see what ur doing? I m working on diy also but a litle dirffersnt

[FDdragon]

i haven't bought everything yet. i just have a couple LED chips and that's it. ha ha. i wanted to get more information before i really started digging in and spending some money. but it looks now like maybe i should just buy.

i work in construction so i might be able to acquire some materials needed and the chips don't seem that expensive.....so im still open to a DIY project. If i do start the project i will let you know and we can meet up.

what kind of system are you doing?

[poakley723]

I am a soldering instructor so if you need some help with that let me know. I also have a nice soldiering iron if you want to call what I have just a soldering iron LOL. Its pretty fancy.

Ebay has real cheap LED everything. I am buying what I want for about 1 - 2 dollars for each 3w LED.

FYI I have some older china fixtures I am modifying with different LED's and optics.

[DaveMorris]

Please don't take this the wrong way, but if you are not real savvy with DC electronics I would not DIY your LEDs. You will end up burning them up and wasting a lot of time, effort, and money.

Input voltage or current has absolutely nothing to do with what the driver actually can do with the LEDs. The input side is AC and the output side is DC and power draw on the two is completely different.

If LEDs are not connected with the proper polarity you will burn them up. This will happen almost instantly so a little mistake will result in complete destruction.

The watts per gallon "rule" is complete garbage. With so many different types of lighting out there using a formula like that is completely silly so don't even worry about that.

If you really want to DIY the LEDs for the experience and/or hobby aspect of it, get a kit from Stevesleds.com or ledgroupbuy.com. They put together all of the parts you need, have simple to follow instructions, and let you know about all of the different cautions involved such as static discharge, proper soldering, polarity, etc. They make it extremely easy and just about as foolproof as it can get.

[unbereefable]

With drivers, you need to pay most attention to volts and amps. Watts is the result of V•A. So first you need to know what power you LEDs can hand and at what voltage. Most 3 watt LEDs are usually around 3V at around 700ma-1A. So lets say your LEDs have max ratings of 3.5V and 1A. Meaning your led cant hand more than 1A of power or its going to be toast. Lets say you've got 12 of these LEDs. So 12•3.5=42. So 42V is your total Vf. So your 48V driver will handle the load. But now we need to know the power. If your driver supplies 1A of power and is rated at 48V, each one of the LEDs will receive 1A. If your driver is rated at 2.5A @ 48V, each led will receive 2.5A. Meaning you'll fry them.

There's a real danger with picking a driver that's over about 54V. Anything more than that will give you a hell of a zap. 54V will zap you too, but there's driver out there that are 100V.

Adjustable current is how the dimming works. PWM is really more for controllers, and 0-10V analog can be done with hard wiring knobs in to control the dimming.

I've got a couple of fixtures I've made for sale. I'm not using them on my next build. There all high quality LEDs and drivers. But they don't dim. They lit my 180 just fine. LMK.

[specvjeff]

Do you want to know another reason the watts per gallon rule is ridiculous? Watts don't have anything to do with output. It describes how much power something consumes. 3 watt LEDS consume 3 watts when provided 100% intensity. Not all LEDS are made equally or run as efficiently. The important factor is your PAR value and to insure you have the proper color spectrum. Frankly once you have the correct blue spectrum the white is just for you. There are more and more studies showing that red LED's have no positive impact on coral growth. Here's why, corals don't receive much red light. Red light is gone after 5 meters. The majority of coral reefs world wide occur below 5 meters... If it were me building a DIY kit, I'd focus on a lower nm blue diode. Something around 420. Then something around 445. I'd include some 8,000k whites and some 12,000k cool whites and call it a day.

Jeff Saurwein
SDMAS President
SDReefs Moderator
Sent from my Samsung Galaxy S4 using Tapatalk Pro

[pigpimpc]

I'm gonna do my diy like this guy:

http://www.nano-reef.com/topic/26743...e-ebay-lights/

I already have my bulbs and sockets and wires. I am now just waiting for my other colors of LED to come in, and then I will be swapiing a few LEDS here and there. The driver/ballast is already in the bulb. Thanks to JADA/ Danny for teaching me that full spectrum is needed for SPS

They have some cheap china led with full spectrum on ebay for 120$ but I don't know how good those are or how my build is going to be :/ Good luck FD Dragon!!!

A good friend told me for diy or for anything to be sure you have the plans and schematics laid out before you do anything and I also heard measure twice, drill once which is good for a beginner like me to hehe.

[FDdragon]

Appreciate the advice!! Im a very fast learner and pretty handy so i think ill be ok with the diy build. I just needed to fully understand the concept so i know how to move forward.

Unbereefable, thanks bro. That info was very helpful. Now i know what to look for and how to stay on the safe side.

Bigpimpc, the build looks nice and i wish you the best of luck. Post pics along the way, would love to see how it turns out.

Jeff, yeah i already have 420 blues and will order some.whites later. Thanks for the info, i might scrap the red thens if there is no poaitive effect to growth. But they look cool though, ha ha.

Thanks again everyone! I will post pics and progress if i do start this build