another led question

[harleymike]

OK, thaoght i would look at rapid led and build my own led suppiment for my t5's.
I was looking at this one, but what sort of power is this. Would it be like adding another t5 bulb. Confused.
http://www.rapidled.com/24-ultra-premium-led-do-it-yourself-retrofit-kit/

 

[dale]

prob better than 2 bulbs

 

[harleymike]

Hmm wonder if i should go for the 12 led then. This is very confusing.
Sorry for all the questions
Mike

 

[ricklalonde]

When you come pick up the frags you can have a look at my retro fit leds. I can show you how they work and what you need.

 

[harleymike]

When you come pick up the frags you can have a look at my retro fit leds. I can show you how they work and what you need.

Thanks rick
I will do that.

 

[KBennett]

Just compare the wattages as equal as a good starting point.  Use 3 watts per LED - even if you are looking at 5W LEDs because you probably won't drive them to over an amp.

For instance, if you have 54W of T5, replace with 18 LEDs.  If it is too much, you can always dim it.

LEDs are slightly more efficient, but you probably won't run them full out.  The real savings is in not having to replace them every 6 months, plus being able to dim them.

Are you thinking all royal blues?  or adding whites as well?

 

[harleymike]

Not replacing t5's yet. Just supplementing them.
Probably 50/50 white and blue.
For the price of a reefbrite strip, I can buy these for less.
I can probably get the aluminum strip too mount them on from work for nothing.
Mike

 

[KBennett]

You'll want a 2:3 ratio rather than 50/50, especially if you are running them in the same string.  The white is easier for us to see and isn't used as much by the corals.

 

[harleymike]

Just so i get this straight. More blue than white. I do like a blue look more.

 

[Boga]

Hmm wonder if i should go for the 12 led then. This is very confusing.
Sorry for all the questions
Mike

I would go for 24 LED's. Two drivers, one for Cool white and one for Royal Blue. You can adjust your ratio blue/white as you like. I have used the same type of LED's in my build.

 

[harleymike]

ok, so from what i can tell after looking into the cree led's.
They are 4.9 watts at 1.5 A.
They are actually driven at 4.2 watts at 100 percent
So a 12 led setup is close too the same wattage as a 48inch t5ho bulb.
I THINK. LOL
But from what I understand, it would probably put out more par than the t5.

 

[Neopimp]

Differen colours run different amps.  1.5A through a blue would likely kill it.  Reds are 700ma max.  The whites can run at higher amps.  And the newer LEDs chips can take more.    I am just spouting numbers from when I built my fixture.  Things may have changed.

 

[KBennett]

I don't have any 5 amp LEDs, but I imagine they'd get pretty hot.  Temperature affects forward voltage and can limit the current you can pump through.
I don't think many people run the over 1 A

Sent from my HTC Desire HD A9191 using Tapatalk 2

 

[Boga]

ok, so from what i can tell after looking into the cree led's.
They are 4.9 watts at 1.5 A.
They are actually driven at 4.2 watts at 100 percent
So a 12 led setup is close too the same wattage as a 48inch t5ho bulb.
I THINK. LOL
But from what I understand, it would probably put out more par than the t5.

Cool White XP-G have max 1.5 A, recommended 1.2-1.3 A.
Royal Blue XT-E have max 1.5 A, recommended 0.7-1.3 A.

Maybe you should stop at 100%, probably at 1.3Amps? I would not push them higher, unless you plan for serious cooling.

I think that 12 LED's (at 1.3 Amps) would put more PAR than one regular T5 (i.e. 54W). Cree LEDs are known for good PAR. Most folks run them at lower current because they want less heat complications, longer life, less noise from fans, etc.

I think they have to be on separate strings (and drivers) becasue curent vs light output is different on Blues vs Whites.

But you can start with more Royal Blues if you want. If I remember right, those drivers allow up to 15 LED's per driver, so you can buy two more RB's and have 14 RB's on the blue string and 10 or 12 on the white string.