DIY LEDs

[jd]

There is a slight problem with the driver. Its does a poor job at being a current source. Instead of being set at 700mA, its varies with input voltage, something it shouldn't do. It just so happens to work out at 12V current draw is 700mA, but anything over there and the current jumps up. 

[cyberwollf]

There is a slight problem with the driver. Its does a poor job at being a current source. Instead of being set at 700mA, its varies with input voltage, something it shouldn't do. It just so happens to work out at 12V current draw is 700mA, but anything over there and the current jumps up. 

You got the circuit wrong then  I have used lm317 for constant current up to 2A i think.  If your input voltage is too low, that will drop your current, but if you raise the voltage above that level it shouldnt affect amps. 

Should have PAR readings this weekend.

If you are lucky

[chromiumlux]

One of these leds would be like a 400w mh only more focused like a spotlight. depends on which lens you get. a 4 something or other to focus it straight down instead of dispersing the light wavelength. can bleach corals fairly quick

[jd]

You got the circuit wrong then  I have used lm317 for constant current up to 2A i think.  If your input voltage is too low, that will drop your current, but if you raise the voltage above that level it shouldnt affect amps. 

*sigh*

I guess that is what I get for making a circuit at 2 am. Found the problem, will fix it tomorrow...

[jd]

One of these leds would be like a 400w mh only more focused like a spotlight. depends on which lens you get. a 4 something or other to focus it straight down instead of dispersing the light wavelength. can bleach corals fairly quick

Exactly! LEDs can be use to spotlight certain corals and areas without wasting power. Bleaching is an issue, as with an lighting upgrade.

My next large tank will likely have T5's to illuminate the whole tank, and LEDs to spotlight areas.

[cyberwollf]

My next large tank will likely have T5's to illuminate the whole tank, and LEDs to spotlight areas.

+1 hopefully the price will drop in the meantime

[jd]

Its getting there now, thankfully. Royal Blues are still expensive, but whites can he had for fairly cheap.

[jd]

And for the record, the pin-out of the LM317T is exactly opposite of what it should be. 

[HUNGER]

cant wait till they get a buck a piece than im in lol

[reefman]

From what I see the white and blues are the same price!

[cyberwollf]

From what I see the white and blues are the same price!

Yea, for white Q5's i have always seen them within $1 of price.

[rayk]

Okay, so how many do I need to light a 2 foot by 2 foot area of tank, but just good enough so it doesn't look 'dark'.  I just need some basic lighting for now on the sides, maybe equivalent to 2 VHO daylight bulbs.  I'll keep my corals in the center.  I would like to do some softies on the sides, as the wifey likes the 'movement'. 

VHO option:
 - 24" bulb is $22 roughly, and 20 watts each x 4
 - $10 for end caps x 4
 - $26 for new Icecap 660 wiring harness (unless I just splice together wires)
VHO total roughly for my two ends at 2 foot by 2 foot = $144 roughly

I really like the focusing idea, and the 'expandability' factor.  I can get some now and wire them up farther apart and with a spread optic, and then later on when the price comes down, re-wire the ones i have and add more for density or focusing. 

- Rayk

[cyberwollf]

15 LEDs would run you about $100 and leave you $40 for power supply, drivers, heatsink, fan... That maybe a little optimistic.  maybe go down to 10 LEDs.  With no optics, i think they run 90degree spread, how tall is your tank? I think we'll need to do a little research to see how much PAR we would get at that depth to ensure we have enough LEDs for softies....Also some softies require much more PAR than others, so that would matter too.

[rayk]

Tank is a standard 180, so 24" deep, but will have a 2" sand bed probably, so 22" at depth.  I'm not so concerned about matching the VHO price, but if I'm going to spend some cash, I'd rather spend it on something that a) can be upgraded b) is a newer technology to play with and c) uses less power and causes less heat.   I didn't even price in the replacement bulbs and cost of actually shipping lightbulbs.  So, cost of LEDs could be $200 to $250 and still map out cheaper with all the benefits. 

I'll try to dig around, but those dang reefcentral threads get so long, and so many questions interjected.  I did see one where BeanAnimal actually got banned for a few days because he was questioning an LED vendor about actual PARs, etc.

- Rayk

[cyberwollf]

I did see one where BeanAnimal actually got banned

 

for a few days

    Man I hate that guy! Yea we need to do some testing locally.  Didnt someone buy a 18 or 24 LED kit? I'd like to take some PAR measurements on that thing.  RapidLED.com will give you some good prices to figure in your budget.

[jd]

I hate that guy too. Hes a 'I'm right and that is all there is too it" person.

White LEDs can be had for around a $1-$2 cheaper than blues, as Wes said.

http://www.dealextreme.com/details.dx/sku.2394

I plan on doing some extensive PAR testing with them in the next week. I need to order a few blues also. My modules are easy to make so I can play around with spacing and alternating the colors.

[cyberwollf]

Does deals extreme have any way to prove the q5 binning? im always leery of the ONE website selling them for $1.50 less (Almost 25% off) ....

[jd]

I know that quite a few people have got them on RC, as far as a proving it, who know. They have a packing label from cree thats says q5, but that is kinda meaningless. Can you confirm that nano-tuners's LEDs are Q5? It's really hit or miss. If we had a lm meter we could be for sure.

[chromiumlux]

Why would a supplier market them as q5 and send something different. I dont understand

[jd]

They can get the lower grades for cheaper and mark them up. Mine came from hong kong so who knows what they are. I'm happy with them either way.

[cyberwollf]

AND you CANT tell the differnce visually. They are all the same identical part. They just do in plant testing and sell the better performers for more (binning). How many poeple have the tools to ensure a "discount" 3rd party supplier is telling the truth?

[reefman]

I just do not understand!!!

[reefman]

so how is this LED doing JD?

[jd]

Very well. Its for some AOG Plays and a Branching Porites that are doing well. I need some royal blues to color them up, but I haven't ordered any yet.