Diy Led Rig

[StandbySetting]

I've just broken up from college so I have 7 weeks to kill and I'm not pleased with the light on my current set up, so I need a project to keep me entertained for a while, I've been reading through SuperColey1's guide on the Green Needle website to get an idea of what I'll need, so far I can deduce that I'll need 6 or so LED's, bearing in mind this is a 54 Litre, 2*1*1' tank. My understanding is that I'll need a 12V transformer, (Could I use a 24V if I could source on?) that has a current out put of at least 0.7A, A current controller, wiring which I have and some form of heat dissipation, I guess I could use fans and heat sinks similar to how SuperColey1 did.

Bearing in mind I'm trying to minimize the number of plugs I use, could I instead use a 24V transformer that has a current output of >0.7A to power 6 LED's, instead of 2 12V transformers? My guess is yes. I guess I could use less LED's? It is a low tech set up afterall and I'm after minimal light (0.5-1WPG (I know this rule can't really be transferred to LED's, but I need a similar light output))

Making a unit for it all to sit in would be easy enough as I have some sheet aluminium I can use.

I presume I'd need to suspend the unit due to the direction and emission of light that the LED's produce, or is there a form of diffuser I can use? The maximum height I can suspend is about 30-45cm as the tank is below a window sill.

Sorry for the long post, any help will be gratefully received, thank you.

 

[SuperColey1]

read the mkII one which will answer some of the questions. Tell me when you've done that and we'll go from there

Andy

 

[StandbySetting]

Right, just read through that, I think I have a basic grasp on the electronics, it's just equipment that I need a little help with.

I've been looking at LED's on ebay and I found these:
http/www.ebay.co.uk/itm/5x-White-High-Power-LED-Bulb-Lamp-Light-3-Watt-3W-DIY-/230649054562?pt=UK_BOI_Electrical_Components_Supplies_ET&hash=item35b3c14562#ht_2954wt_905

I presume the little star thing it is attached to acts as a heat sink and a mount, I read in your journal that you used thermal paste, I'm not familiar with it but is it purely for conductivity of heat from component to component?

I'm just unsure as to how many LED's I would need, how many would you recommend?

Did the LED lenses you use act as a form of light diffuser or did they concentrate the light into a beam? I see from searching that they come in different angles.

Your help is much appreciated thank you.

 

[SuperColey1]

I've been looking at LED's on ebay and I found these:
http/www.ebay.co.uk/itm/5x-White-High-Power-LED-Bulb-Lamp-Light-3-Watt-3W-DIY-/230649054562?pt=UK_BOI_Electrical_Components_Supplies_ET&hash=item35b3c14562#ht_2954wt_905

These are the right ones however it doesn't mention the K of it. as long as it is cool white or 5500K then it is fine. Don't want the 'warm white' ones though unless you want a yellow tank.

I presume the little star thing it is attached to acts as a heat sink and a mount, I read in your journal that you used thermal paste, I'm not familiar with it but is it purely for conductivity of heat from component to component?

It is supposed to act as a heatsink but I wouldn't risk it. Yes it dissipates some heat but with that kind of heat you really need more. I used thermal paste because I had some however thermal pads would be better because I then had to superglue over the edge to stop them sliding along. It is to 'close the gap between the star and the heatsink just like is used between a PC processor and the heatsink.

Cna't remember why but I wouldn't stick them all on an aluminium plate. Connects them all up together or something like that. I separated mine and original put them into an acrylic board. Then when I reworked it I used the lenses to hold each unit into the wood.

I'm just unsure as to how many LED's I would need, how many would you recommend?

I would suggest just over 1W per USG and then you can raise/lower it to achieve low and highlight. This is 1.12WPG with the light 80cm above the waterline!!! Thats 1.15 metres above the substrate:

That is going to be pretty much equivalent of 1WPG on the scale at that height. Put it down to a traditional height I am pretty sure we are talking very high light. I think for yours 2 rows of 3 (6 total) that would be fine.

Did the LED lenses you use act as a form of light diffuser or did they concentrate the light into a beam? I see from searching that they come in different angles.

No they are 45degree lenses. They don't diffuse they focus. Like a reflector does for fluoros. If they are very close to the water (2 inches) the beams are visibly seperate from each other. however most purposes will use a much narrower angle like 20 or 30 degrees. These are fine at 4"+

A 24V input would be fine for all 6 LEDs linked in series with the drivers I am using for 3. I used 3s so I could get the staggered lighting but that driver can do 6 @full power or 7 at limited.

In essence I would measure your tank dimensions exactly. Then divide that along the middle on the shortest side (front to back) and into thirds on the longest side (left to right) You now have 6 equal areas. Each LED goes into the centre of these areas.

That is basically the spread sorted. All you need to do then work out your own preferences and the electrics.

By preference I mea do you want the unit to be the same footprint like mine is or do you want it to be as small as possible. I made mine the same because it is a continuation from the floor the cabinet, tank and light width and depth are equal. However once you have your 6 LED positions sorted you can go in as close as you want to the corner ones. They will still be spread the same, just their encloseure smaller.

I would definately use the optics. Tidies the bottom side up really well and also makes it much easier as the LED die just pushes into a shaped entry on the rear. That way you can just remove the LED string very easily if needed. They are basically 'push fit'.

This way the lense holders are the fittings. The electrics just 'push fit on the rear. I would definately use proper heatsinking and forget the fans as long as there are ventilation holes. I don't use the fans anymore.

The seller you have linked to is the same one that I used and I got the heatsinks, lenses there as well.

I got the drivers (you will only need one) from here:
http/www.ebay.co.uk/itm/Power-LED-Driver-830mA-Output-8-24V-DC-Input-Solder-/250842309786?pt=UK_BOI_Electrical_Components_Supplies_ET&hash=item3a675de49a

DO NOT BUY THE DRIVER ABOVE AS IT WILL OVERPOWER YOUR LEDs. He doesn't have any suitable drivers listed at the moment so pm him and ask when he will get some 650-700ma ones.

Then just get a 24V DC power source that is over 700ma Job's a good un.

That LEDs, heatsinks, lenses, drivers, wire, adaptor shuold cost you circa £50 or less. The box is down to how fancy you want to get

Definately easier to have access through the top (MkII) though rather than through the bottom (original) and easier to make it look cool too

Andy

 

[StandbySetting]

Thank you very much.

Should I go for 45 degree lenses in that case?

I have two transformers already, they're old 12V scalextric transformers, presumably I just snip the ends off and then connect them to the driver? They're both black cables though, do you know how I could determine the polarity?


Thanks

 

[StandbySetting]

Here's a first draft of the drawing:

The luminaire won't cover the whole of the tank as I want it to be as light as possible, I've ordered LED's, I just need to order drivers, thermal pads and lenses now.

Thanks for your help.

 

[SuperColey1]

Thank you very much.

Should I go for 45 degree lenses in that case?

I have two transformers already, they're old 12V scalextric transformers, presumably I just snip the ends off and then connect them to the driver? They're both black cables though, do you know how I could determine the polarity?


Thanks

45-60 degrees is about right. don't go any narrower unless you intend to use more LEDs and have higher light otherwise you won't be able to put it as close to the water without seeing beams. May not be the intention at the moment to have it close but you may want to somewhere along it's 7-10 year lifespan so best to allow for that possibility.

Are you using 2 plugs to power 2 driver and 2 strings of 3? If not and you are using 2 adaptors to power 1 driver you may struggle. I may have done something wrong but I tried that when testing once and it would only use the power from one. something conflictinfg or ....i don't know but it didn't work.

I would say you want a single 24DC source for a single 6 string or you will have to do 2 strings of 3 on the 12V

Normally on plain black leads there will be a white line. or a dashed line or in some cases just the printed info on one of the cables. That is the live one. On many others inside the black there are red/white or red/black sleeves red is of course the live.

Andy

 

[SuperColey1]

Here's a first draft of the drawing:

The luminaire won't cover the whole of the tank as I want it to be as light as possible, I've ordered LED's, I just need to order drivers, thermal pads and lenses now.

Thanks for your help.

Lol. Mine may be big but it is lighter than any MH or overtank fluoro luminaire It is hanging by 2 of the old fashioned cheap Arcadia luminaire cables which are about half the width of bicycle gear cables


Is that diagram a rough sketch? those 'areas don't look equal to me.

The black rectangle is the tank footprint. The red lines divide the area in 2 6 equal areas (mine are rough.) Little red circles are obvs LED positioned dead centre of each of the 6 areas. Then you can make your luminaire where the blue line is. or larger or even bigger than the tank if you're crazy. lol

EDIT. I see what you've done now. That border just looks like a border when on a white backgrounded forum page. lol. I only noticed it when I posted and saw it in the quote which has a different background colour.

Andy

 

[StandbySetting]

The grey area represents the luminaire, and the white area the tank, the yellow blobs are the LED position, sorry for not pointing that out.

Thanks

 

[StandbySetting]

These are the LED's I ordered:
http/cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=280676738369&ssPageName=STRK:MEWAX:IT

Now I'm searching for a driver, in the specs it states that the unit has a current of 0.7-0.75A pass through it, so presumably I need a driver that matches this value? Also when choosing a driver must it have a power rating of the sum of the LED's? So 9 Watts for each circuit? Or would I need just one 3W driver to power all 3 LED's?

I found this:
http/www.ebay.co.uk/itm/LED-transformer-driver-80V-270V-12v-3W-9W-15W-21W-DC-/170663069052?pt=LH_DefaultDomain_0&var=&hash=item6d70278937#ht_3901wt_1139

This is the variant I was looking at:
12V 0.75A(9W)


Thanks

 

[StandbySetting]

Sorry to be a pain, the LED's I ordered draw 700ma-750ma, I've found this driver too, I presume this would be suitable for one series?

http/www.ebay.co.uk/itm/High-Power-3w-LED-Driver-MBI6651-based-Luxeon-700ma-/220816213881?pt=LH_DefaultDomain_0&hash=item3369ac0779#ht_4577wt_958

 

[SuperColey1]

Sorry to be a pain, the LED's I ordered draw 700ma-750ma, I've found this driver too, I presume this would be suitable for one series?

http/www.ebay.co.uk/itm/High-Power-3w-LED-Driver-MBI6651-based-Luxeon-700ma-/220816213881?pt=LH_DefaultDomain_0&hash=item3369ac0779#ht_4577wt_958

This one will run all 6 LEDs if you put a 24V source into it. Or 3 LEDs with 12V in which case you would need 2 plugs and 2 drivers and 2 series of LEDs

Andy

 

[StandbySetting]

Thanks very much, I'll get all of the equipment ordered tonight!

 

[StandbySetting]

One last question, what current 12V transformer should I use for this driver:
http/www.ebay.co.uk/itm/High-Power-3w-LED-Driver-MBI6651-based-Luxeon-700ma-/220814282565?pt=LH_DefaultDomain_0&hash=item33698e8f45#ht_4625wt_958

At a guess 700mA, or does it not matter as the driver will control the current for me? I have a 600mA 12V transformer, presumably this wont supply enough current and I'll need to buy a bigger one? Does Wattage of the transformer matter either?

 

[SuperColey1]

One last question, what current 12V transformer should I use for this driver:
http/www.ebay.co.uk/itm/High-Power-3w-LED-Driver-MBI6651-based-Luxeon-700ma-/220814282565?pt=LH_DefaultDomain_0&hash=item33698e8f45#ht_4625wt_958

At a guess 700mA, or does it not matter as the driver will control the current for me? I have a 600mA 12V transformer, presumably this wont supply enough current and I'll need to buy a bigger one? Does Wattage of the transformer matter either?

Needs to be 700ma or more. doesn't matter if it is 2A (2000ma) as it will only draw what it neds but must be = to or greater than.

No idea what you mean r.e. transformer really. I am no electrician. I just use those variable voltage adaptor plugs

Andy