[SuperColey1]

I have decided to 'probably' waste some money. lol. Don't ever let the housewife tell you that she is overworked. My house is incredibly clean. The washing basket is empty, the cupboards are full of food. the oven is clean etc. etc. and I am soooo bored with nothing to do so this project is a must for me now I'm house husband. lol

I want however to do this the cheap, easy way for me if possible and was thinking of this idea;

Each individual 3W 700ma 3.67V LED to be mounted individual screwed to the wooden hood like the diagram below:

blue is a bent strip of aluminium, red is a heatsink, green is the LED, black are screws/bolts

Then 16 of these individual units wired in groups of 4 to seperate 12V 700Ma plugs(DC/AC adpator plug) using a 12V current controller making 3V into each LED:

blue are the individual units, red and black are the+/- wires, green is the current controller and pink is the wire to the DC adaptor.

Also in this diagram there are 2 in fans and 2 out fans. All the heatsink fins would have be lined up with their fin ends facing the fans. There would then be a simple piece of clear perspex or glass 2 inches below the LEDs that would seperate the water from the airflow to avoid too much evaporation.

Question. Have I got this right. I know its not perfect but will it work. Should I use thermal tape/grease in between the LED/aluminium/heatsink of each unit etc. Is it a good idea to keep it as individual from a replacement point of view?

AC

This post has been edited by SuperColey1: 14 July 2010 - 08:58 AM

[nitro7]

SuperColey1, on Nov 22 2008, 12:10 PM, said:

I have decided to 'probably' waste some money. lol. Don't ever let the housewife tell you that she is overworked. My house is incredibly clean. The washing basket is empty, the cupboards are full of food. the oven is clean etc. etc. and I am soooo bored with nothing to do so this project is a must for me now I'm house husband. lol

I want however to do this the cheap, easy way for me if possible and was thinking of this idea;

Each individual 3W 700ma 3.67V LED to be mounted individual screwed to the wooden hood like the diagram below:

blue is a bent strip of aluminium, red is a heatsink, green is the LED, black are screws/bolts

Then 16 of these individual units wired in groups of 4 to seperate 12V 700Ma plugs(DC/AC adpator plug) using a 12V current controller making 3V into each LED:

blue are the individual units, red and black are the+/- wires, green is the current controller and pink is the wire to the DC adaptor.

Also in this diagram there are 2 in fans and 2 out fans. All the heatsink fins would have be lined up with their fin ends facing the fans. There would then be a simple piece of clear perspex or glass 2 inches below the LEDs that would seperate the water from the airflow to avoid too much evaporation.

Question. Have I got this right. I know its not perfect but will it work. Should I use thermal tape/grease in between the LED/aluminium/heatsink of each unit etc. Is it a good idea to keep it as individual from a replacement point of view?

AC

hi SuperColey1
have a look at my topic (worth a look ) in hardwear,page 2 i think .people gave me lots of advice on l e d and how to wire them ect ,ect

[SuperColey1]

Thanks for the reply Nitro. HAD a look through your thread but this is a different baby altogether. lol

I am looking at using 16 high power 3W LEDs. If I were to use the normal LEDs that you are I would be looking at 200-300!!!!

Also its in the hood rather than underwater. This can't be an 'effect' it has to be an even spread as it will be the actual lighting in a planted tank and therefore the light needs to be good, well spread and look as if it were 1 light!!!

This presents its own problem because these 3W LEDS get red hot to the point they bend the metal they are mounted on and therefore need to be heatsinked and insulated from the heatsink. Then I have to sort a flow of air through the part of the hood that contains the heatsinks to cool them down or they may start to 'boil' my fish. They also need current controllers rather than using simple resistors.

I'm also trying to run them in seperate series so that I can stagger the lighting through the day (sun moving left to right)

Thanks for the reply though. interesting thread there. hope it works for you. I have Cold Cathodes in the hood at the moment and moonlight looks cool.

AC

[andywg]

Aha, 3W LEDs as main lights!

They are an interesting beast. The best advice I can give is to look at some of the LED threads on Reef Central regarding how to set them up. There are even some posts on there from the people who have developed commercial LED lighting for reefs.

If you are doing them for planted you aren't after the sort of light required by reef tanks which works in your favour. The reflectors are an important part of the LEDs for sorting out getting the right PAR levels at depth.

[SuperColey1]

andywg, on Nov 22 2008, 04:55 PM, said:

Aha, 3W LEDs as main lights!

They are an interesting beast. The best advice I can give is to look at some of the LED threads on Reef Central regarding how to set them up. There are even some posts on there from the people who have developed commercial LED lighting for reefs.

If you are doing them for planted you aren't after the sort of light required by reef tanks which works in your favour. The reflectors are an important part of the LEDs for sorting out getting the right PAR levels at depth.

I originally got the idea from one of the reef forums but the chap wired them up with no current controller, just a variable DC adaptor then someone else decided to try it too and the results were great until the LEDs burnt out!!!!

Great idea but a vital ingredient missed out.

I have since altered the plan above due to me researching voltages etc. lol.

The idea was 4 parallel sets of 4 x3W on 4 seperate timers.
Due to the controllers need 1.5V of the 12V it pushed that idea out.

I am now looking at 5 series of 3 x 3W on 5 seperate timers. lol

I'll get a new diagram and some piccies up of the proposed items later on but back to researching for me now. lol

AC

[SuperColey1]

Here is the modified plan:


AC

[SuperColey1]

Does this look right?

This plug runs 900ma at 12V. the current controller is where I think I may be wrong. I have points for positive supply (+), negative supply (-), control input (A). Then on the oposite side I have positive and negative cathode which I assume are where to connect the LED series to

From the positive cathode I then enter each LED on a positive and then exit the LED on a negative to join the next LED on a positive. At the end of the series I then return to the negative cathode on the controller.



AC

[Rooster]

You stated that each unit runs at 3W 700ma 3.67V therefore the PSU you are planning to use isnt man enough (3 x 700mA = 2.1A)
If I were planning this, I would get a BIG single PSU, maybe an ex PC job... with loads of Amps, then treat each LED as an individual !
If you need to switch groups, use relays.... zero loss !

[SteveyG]

Rooster, on Dec 7 2008, 02:35 PM, said:

You stated that each unit runs at 3W 700ma 3.67V therefore the PSU you are planning to use isnt man enough (3 x 700mA = 2.1A)

They're wired in series with a CC driver, so 700mA in total. No problem there.

Rooster, on Dec 7 2008, 02:35 PM, said:

If I were planning this, I would get a BIG single PSU, maybe an ex PC job... with loads of Amps, then treat each LED as an individual !

Treating each LED as an individual would be a poor way of doing this. You'd need a driver for every LED! Highest efficiency (cost and power) is obtained from switching CC drivers and chains of LEDs in series. That way you'll get better brightness matching too.

Rooster, on Dec 7 2008, 02:35 PM, said:

If you need to switch groups, use relays.... zero loss !

Contact resistance? Coil power?

This post has been edited by SteveyG: 09 December 2008 - 12:40 PM

[Rooster]

Quote

They're wired in series with a CC driver, so 700mA in total. No problem there.

Quite right... didnt engage brain !

This post has been edited by Rooster: 09 December 2008 - 12:45 PM

[SuperColey1]

my wallet just said............phew!!!!

[SuperColey1]

Well I got bored and had a go at a series of 3.

Running from a 1000ma 12V adaptor. This is a pic of 9W of light in my living room with everything turned off (The camera is 12ft away from the LEDs and looking from the sides)


And here is a pic from 2ft away directly above. (My eyes are aching just from taking this pic!!!! Its like welding flash (if anyone knows what that is. Hope my retinas aren't burnt and wake me up in agony through the night )


I will admit it didn't go as smoothly as I would've liked. This post was begging for advice until I edited just now. It wasn't working and then I decided to try each LED. 1 worked and the other 2 didn't. I think I may have burnt them trying to make the solder too neat and taking too long. Got 2 fresh ones and went splodge, splodge and then it worked.

One lesson learnt

AC

This post has been edited by SuperColey1: 22 December 2008 - 02:22 AM

[SuperColey1]

As a final post of my test, I put the series of 3 on the front flap of my hood just to see what they look like. Wrong way round as it is 3 left to right whereas I will have 3 front to back and then 5 rows across. Crudely fastened them into my hood.

If anything I think the light looks better than the fluorescents!!! You can see the ripples on the substrate and shadows moving from the leaves etc. looks really cool.

So these LEDs at max are 3.7V. I am putting 3.5V in so I assume that means instead of pushing out 3W they are pushing out 2.8W?

Anyway here is the series attached to the front flap of the hood:


This is a close up of the LED and heatsink screwed into the flap:


This is how the tank looks with 48W (1.45WPG) of 4500K/6500K Fluorescent (This pic was at night with all the lights off etc):


This is how the tank looks with 8.4W??? (0.25WPG) of 5500K LED all at the front (This pic is in daylight):


And a quick pic of the ripples/shadows:


Have to say I like it but thats where I stop for now. I have to get the rest of the LEDs and that will not be for a little while so tested, happy and confident it will work I can start planning a more suitable mounting method etc.

AC

This post has been edited by SuperColey1: 22 December 2008 - 10:40 AM

[smithrc]

Looking good matey

Its dark now - get another picture with the lights off for a direct comparison


on a really random note - I was staying in a premier inn last week and they have cool reading lights by the bed - when I took one apart (yep - I get that bored in hotel rooms!) it was as I expected... a luxon LED

[SuperColey1]

I'll do it later (wife goes mad if I turn the TV, PC and lights off etc)

I would hear 'Why does everyone else have to suffer just so you can take yet another photograph'

AC

This post has been edited by SuperColey1: 22 December 2008 - 10:59 PM

[Schmill]

Looking good, looking forward to the nighttime shot

[SuperColey1]

This is my plan for the mounting board. I took an old 29" T5 reflector and cut it into 1.75" pieces to mount the heatsinks and LEDs on. They will act as more heatsinking. The reflector part won't really come into play but may stop some glare from direct view through the gap between the tank and 'luminaire'



And these are the fans on the 'in' side of the 'luminaire'. The other end is identical. Yes before you ask I have turned the fans the other way round at the other end so they are not both blowing air into the luminaire. The left set of 4 will pull air in and the right set of 4 will pull air out.



So waiting for LEDs now. I have actually done 3 series and fixed them to the mounting board complete with their controllers. When I get the final 10 LEDs I will do the other 2 sets. Then all I need to do is to wire everything up and fit an acrylic sheet into the bottom of the luminaire to 'close' it off.

AC

[rabbut]

I'd be tempted to leave it open unless you antisipate a lot of splashing. Algea magnet waiting to happen and many Acrylics will reduce the amount of light passing through it, not to mention that they tend to scratch when you remove the algea, further reducing light through-put If you need to cover them, save some long-term £ and get a glass cover

Otherwise, it all looks good I don't suppose you have a link to where you got those LED's from do you? I'm doing a LED set-up for marine, but I want it dimmable. This means making my own controller(s) for the LED's, but I'm comming un-stuck finding the corrent LED's for the job. The highest output LED's I've found so far would require me to use 300 and something of them to do the job of my 150W halide... If you get good plant growth with these, I may give them a worl on my Marine...

All the best
Rabbut

[SuperColey1]

I'm not anticipating splash nor algae on the acrylic as I think it will need raising to about 12"/18" above the tank due to the brightness. The Acrylic is more to keep the air coming in from the sides within the unit rather than escaping downward to the tank. I don't want any more evaporation. lol

Link to the LEDs (cheaper to buy them in 5s at auction than buy it now on qty 20s

http://cgi.ebay.co.u...e...A:IT&ih=015

AC

[xxBarneyxx]

Brilliant. Looking at these potentially for marine as well. I dont suppose you know anyone with a PAR meter do you as I would really like to know what the par is like from these LEDS at different depths.