Ultimate LED guide

[evilc66]

You could just mount the pucks inside the hood and have a single jack for the 24v DC power from the power supply. Try and keep te Buckpucks in the open. They seem to have an issues with overheating in tight enclosed areas.

[mg4015]

ok, i should have all of the buckpucks wired to a single dc jack(protruding from the hood) and have a dc plug wired to the power supply connected to it. that would be great. i would have all of th buckpuck = and minus wires linked together accordingly for this, correct? i also saw that the dc jack is three prong, with a ne, neutral, and hot, but htere are only two optiions on a buckpuck. skip the neutral?

[mg4015]

also in post 121 of this thread: http://www.nano-reef.com/forums/index.php?...t&p=2259380 it is mentioned that dc hooked to high currents can be dangerous if hooked up improperly, and since i tend so spill a little water when i do mantenance, i am concerned about exactly how to properly wire these things so this does not happen.

[cptbjorn]

Which DC jack are you using? A lot of them have 3 terminals and one is a switched terminal that is connected to the positive when there is no plug, but when you insert a plug it becomes connected to nothing. It is usually best to plug the power supply into the wall and connect just the bare jack onto the power supply plug and then test with a multimeter to find out exactly which terminals are the + and -.

 

Nevermind that post about it being dangerous, as long as you are just running 24v DC through the barrel style jacks it isn't a problem. He has either changed the way he had it or I misinterpreted one of the pictures but I though he had the full 120v wall current going through one of those plugs. 24v and under generally can't do much to a healthy person which is why there is a big difference between normal AC and DC cables; you don't really need to worry about the 24v side.

[mg4015]

ok that makes sense. so you would wire the buckpuck wires to the respective + and minus terminals on the barrle jack, and wire the dc plug to the power supply, right? the power supply then connects to the wall.

[Sherman]

Today take some PAR reading from my existing 250w MH.

The bulb is Hamilton Tech 14k, 250 w

Below is the reading I get from my newly acquire Apogee Quantam Flux

Setting is Sun

 

Par Reading

 

Depth * MH(250W)

4 IN. 200 - 340

5 IN 185 - 280

6 IN 180 - 270

8 IN 150 - 218

 

 

NB.: Light is 4 inch from water top

* From water top

 

MH reading is taken where the reading is the strongest.

That is within the light enclosure

[evilc66]

What kind of reflector was used?

[Sherman]

Its a normal reflector found on most commerical MH light set

[evilc66]

Hmm. Seems a little low from my experiences with taking PAR readings.

 

I'll take some measurements of my 150W Phoenix when I get home as a comparison.

Edited May 20, 2009 by evilc66

[Sherman]

For taking the PAR measurement is it just set to Sun,sample and then take reading at different points and depth with the sensor head white spot pointing towards the light source to be measure?

Don't have to do any thing before taking reading?

There is no manual that tell us what to do?

evilc66 ready need your expertise

 

Maybe can publish your PAR measurement for MH and LED for us to reference.

 

Thank You evilc66

Edited May 21, 2009 by Sherman

[evilc66]

Sounds like you are doing it right, but the numbers are way off. For comparison, over my BC14, I have a 150W Sunpod, with a Phoenix 14K bulb (about 4 months old). Fixture is 4" from the water and at 6" below the waterline, directly under the bulb, I took a reading of 450-460 PAR.

[Sherman]

Wow your reading so good. I must try again

[Sherman]

I try to take reading again just now.

MH is 4 inch above water top .

At 6 inch below the water top I only get 300

 

evilc66 what do you think is the problem?

[evilc66]

Hard to say. First thing I would check is the wattage draw of the ballast. A device like a Kill-a-Watt can be plugged inline to the ballast to measure what it is pulling. Electronic ballasts should be close to 250W +/- 10%, and magnetic ballasts will be over 250W. You mentioned it was a Hamilton bulb. How old is it? It shouldn't make that big of a difference, but we might as well make sure that it isn't the issue.

[Marteen]

Hey evil what size drill and tap are you using for these cree XR-E LEDs? I've finally got a chance to run down to homedepot this weekend and want to get everything I need to finally finish my LED fixture.

[evilc66]

I use M3 screws personally, but you can also use 4-40. You will usually find the drill and tap together, but tap drill charts are easy to find on the net.

[Giga]

so do coral not look as good unless you add uv so they have a uv output like MH?

[evilc66]

That is yet to be seen The focus on the use of UV has mainly been for sps coloration and health. Lps and softies don't seem to be affected in the same way. I have had some sps do just fine color wise under LEDs without UV. Some people report less than satisfactory color under LEDs. My UV meter came in today, so I will be starting to gather data to see what we have to do, if we have to do it. The main problem is that we only have one source for UV LEDs so far, and the quality is questionable. It would be great if Cree, Lumileds or SSC did a UV.

[mg4015]

hey i gotta question on how to wire my fans for my setup. im going to be using 4 of these: http://www.silenx.com/ixtremaprofans.asp?sku=ixp-11-14

and 2 of these for exhaust http://www.silenx.com/ixtremaprofans.asp?sku=ixp-34-16

 

what is the best way to wire these up? will i need a seperate power supply just for fans? i have heard that wiring them in series works for two fans, so should i have them wired in a series of three, with two in each one? that would make the fans wired in series, but the current would be the same through all , right?is this excessive cooling for an LED setup?

[evilc66]

Go bigger. Larger fans pucsh more air for less noise. I know the SilenX fans are silent already, but a single 80mm or 120mm fan directly blowing down on the heatsink will provide better cooling than many small fans blowing end to end.

[mg4015]

ok. still the same question on wiring. not that it is only three fans, should i still wire them all in series (24V/3), or should one be at 24 V and the other at 12 v(24/2 because they are in series)

[djprofd]

ok. still the same question on wiring. not that it is only three fans, should i still wire them all in series (24V/3), or should one be at 24 V and the other at 12 v(24/2 because they are in series)

 

 

i believe, and feel free to correct me, that if you wire 3 fans in series to a 24V power source,each fan would be running on 8V.

 

you add voltage when wired in series.

 

Is that correct evillc?

 

d.

[deepdvnarq]

ok. still the same question on wiring. not that it is only three fans, should i still wire them all in series (24V/3), or should one be at 24 V and the other at 12 v(24/2 because they are in series)

 

when you wire something in series, you keep the current constant and the voltage is added. like your led setup. that's why the biggest voltage ever needed when using buckbucks is 24 (6leds x 3.7 + buckpuck= pretty darn close to 24v). when in parallel, the voltage stays the same throughout and the current gets added(the reason for current mirrors in strings of leds) there was a discusion on another thread about this same thing trying to wire 3 12 v fans together using a 24 v power supply. with this, best to use it in even numbers or just get a 12v walwart for like $5 and run everything in parallel and as many as you want as long as you dont surpass the current rating of the walwart, but that's pretty hard to do. most fans use .08a

[deepdvnarq]

is there a way to formulate approximately how many LEDS it would take to equal a certain MH wattage. for example, if i wanted to get at least the same par output or of a 250W, how would i formulate an array on how many LEDs to use. i know optics have some to do with it too and the depth of the tank.

[mg4015]

thanks for the info on the wiring. can you show me a link of where to buy a 12v walwart with sufficient current?

 

from what i have read (i have yet to build my own setup) 40 degree optics will get you to 250 watt levels. the only other factor to consider is spacing, if you wish to eliminate spotlighting with a tight optic. i will be using 24 leds on my aquapod, with 60 degree optics if they fit under the splash lense. hope that helped