DIY LED 220w Cree XTE + Philips ES

stardustsailor

stardustsailor

Well-Known Member
Oslons SSLs are precious shining diamonds !
drawing.jpg.....

And they are really tiny ....
Just ~3x3 mm !!!

They can be only reflow soldered ....
Which actually ,is easier than normal soldering ,somewhat .....

Secret of successful reflow- soldering ,lies on solder paste temperature and stencil design quality/thickness...

Forget about gluing 'em onto a pcb of some sort ... ....

Only lead -free ,(silver/copper) solder alloy can be used .....
And even better ,in a neutral Nitrogen atmosphere-if possible-,to minimise reaction of solder with atmospheric oxygen .....
(Oxidation,bubble forming )
 
SupraSPL

SupraSPL

Well-Known Member
Ideal spectrum offers them loose or mounted on stars. I heard somewhere that SSL can be mounted on XP stars and it does seem tricky to find SSL stars in the US.

SDS, do you have any suggestions for solder paste for the SSL? Out of curiosity why does it have to be lead free? I have never tried reflow but I might have to learn DIY reflow for some parts of the next lamp.

XP vs SSL solder pad.png
 
stardustsailor

stardustsailor

Well-Known Member
Just use a good quality solder paste of SnAgCu solder alloy ...

-Copper and Silver conduct heat much better than Lead .
The most important reason why this type of solder is used when reflowing leds .

-Copper and silver are both harder metals than lead ..
Thus solder joint withstands more stress from (different level ) thermal expansions of both mc-pcb and led case .
A solder joint made with lead solder might not last long ,under certain conditions ,when used in leds ..

-Enviromental regulations .Health Safety .
 
SupraSPL

SupraSPL

Well-Known Member
I noticed Steves LEDs selling the Luxeon M. It is similar to the XM-L. It is high voltage so when run at 700mA it dissipates about 8 watts. Here are the numbers for the best available bins:

452nm deep blue C5G bin: 57.7% (700mA 50c)
5000K S35G bin: 40.5% (700mA 50c)
3000K Q75G bin: 34.31% (700mA 50c)

Since XM-L deep blue is not currently available, these are the most efficient blues available on the market, outgunning the Luxeon ES which is 55% (700mA 50c).
 
S

SnotBoogie

Well-Known Member
SSL stars can be had from

Mouser ("Bergquist" is the brand i think)

ideal-spectrum

A place SDS linked me once - led-tech.de i think?
 
G

glennorch

Active Member
This is an amazing thread for sure... I learned a lot as well. Supra may I ask you about the wattage of each panel and the heatsink measures? Is it aprox 50w each?


Do you guys think it's worthy efficiency speaking to use XM-L2 warm whites instead of the double amount of them but XT-E?


Cheers! :)
 
SupraSPL

SupraSPL

Well-Known Member
The LEDs on each heatsink are dissipating about 50 watts each. Each section is 10" long, 6" wide and 2.5" tall with a total surface area of 845 in2 or 5450 cm2. So the formula I am using 17in2/watt or 110cm2/watt to aim for a Tj of 50c.

Regarding XTe vs XML2 I am asking myself a similar question :) 34.5% vs 39%, so XML2 is a 13% improvement for more than 2X the price. Mouser offers lots of choices for XML2 if you are in the mood for DIY reflow soldering.
 
G

glennorch

Active Member
Hey man cheers for the reply... yeah I guess it's not clear yet. The improvement is not amazing to make a big difference. Same with the new Luxeon M neutrals though... isn't it? lol

And by the way, DIY reflow soldering will be tricky for sure!

Thanks and peace bro.
 
tebos

tebos

Member
SupraSPL said:
Ideal spectrum offers them loose or mounted on stars. I heard somewhere that SSL can be mounted on XP stars and it does seem tricky to find SSL stars in the US.
Click to expand...
Yes, you can use XP stars, they have the same footprint (3535). Lead free is just a pain in the ass imho.
 
brotherjericho

brotherjericho

Well-Known Member
SupraSPL said:

LED ratio
KNNA recommended a flowering ratio of 9 red 2 white 1 blue. The perfect ratio is not known exactly but KNNA has a good understanding of it. It does not need to be exact as the plant will adapt. However the less the plant needs to adapt to the SPD the better. The ratio he gave back then depends on the efficiency of each LED so to be more accurate we need to know the ratio in terms of radiometric output. He suggests 15-20% blue for flowering and 20-30% for vegging. The way you divide up the rest is up to you.

I put a spreadsheet together for radiometric output and played with the ratio until I ended up with blue radiometric output at 17%.
7 Lux ES 660nm red
3 XP-E 630nm red
5 XT-E warm white
2 Lux ES 442nm blue
Click to expand...
Is there a tool or spreadsheet available to figure out the radiometric percentage of blue? I am trying to figure out how to get this 15-20%, and its straightforward without the whites, but then you get a blue contribution from them. Or are you ignoring the whites for the calculation?

Thanks!
 
Highocaine

Highocaine

Well-Known Member
Generally ignoring whites for that blue percentage. DIY this day I'd go with red+white. Fewer parts to source, and Cree makes good ones.
 
SupraSPL

SupraSPL

Well-Known Member
brotherjericho said:
Is there a tool or spreadsheet available to figure out the radiometric percentage of blue? I am trying to figure out how to get this 15-20%, and its straightforward without the whites, but then you get a blue contribution from them. Or are you ignoring the whites for the calculation?

Thanks!
Click to expand...
I use a spreadsheet to do the job. It is a very complex calculation and unfortunately it is based on guesstimates of the LER of a given tint of white LEDs. I have counted boxes to try and get an idea of the percentage. I settled on 10% blue for the 3000K XTE WW. The SPD graph green surfer posted was more accurate than the Cree publications (XTE 3100K) and I counted 12% blue. For neutral whites 17-23%. Guod posted his estimates, 8% blue for 2700K, 28% for 6500K. I hope that helps your calculations.

If you post up your exact numbers, bins and driver currents I can easily give you an estimation because I have already calculated the efficiencies of the emitters and bins you are using. Or if you prefer I can upload an XLS.
 
brotherjericho

brotherjericho

Well-Known Member
SupraSPL said:
I use a spreadsheet to do the job. It is a very complex calculation and unfortunately it is based on guesstimates of the LER of a given tint of white LEDs. I have counted boxes to try and get an idea of the percentage. I settled on 10% blue for the 3000K XTE WW. The SPD graph green surfer posted was more accurate than the Cree publications (XTE 3100K) and I counted 12% blue. For neutral whites 17-23%. Guod posted his estimates, 8% blue for 2700K, 28% for 6500K. I hope that helps your calculations.

If you post up your exact numbers, bins and driver currents I can easily give you an estimation because I have already calculated the efficiencies of the emitters and bins you are using. Or if you prefer I can upload an XLS.
Click to expand...
Thanks, but I've already got my order together, so I've got what I've got :-P. With the numbers you just posted, I should be pulling around 11-12% with my reds running, and 18% with them off. That's actually about what I'm looking for, all whites for the stretch phase, and then toss in the reds (on dimmers) once it slows down. My plants go from 6500k fluoros in veg, so going to ~18% blue for first part of flower will be less of a shock. Or at least that is my hypothesis!
 
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