Brotherjericho's stupid questions about DIY and such

SupraSPL

SupraSPL

Well-Known Member
Sounds like you have a good plan. KNNA was convinced that number of photons is more important than spectrum. I think that is especially true in the case of XTE vs Luxeon whites. Cutter is offering the XTE 3000K R3 bin on 20mm stars and they are cheap.

I am in the same boat, trying to get flowering room temps down without running AC too much and without the sound of a tornado from cranking up the fans. DIY LED really knocks those temps down and has the bonus of stickier stinkier buds. I normally get .5gr/watt from 600HPS and have been getting 1gr/watt from DIY LED built similar to what you posted above. I am sure you could get much higher numbers but I am referring to medium yielding varieties. After sampling 100 different females, I have never come across a heavy yielding variety that has the flavor and potency of the best medium yielders.

80% efficient 700mA drivers
90%+ efficient 700mA drivers

Good luck with your build!
 
SupraSPL

SupraSPL

Well-Known Member
brotherjericho said:
So you don't think pushing the reds to their max is a bad thing for longevity?
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SB is right, cooling (heat spreading) is what matters because the longevity ultimately depends on the junction temp rather than the current (as long as you don't exceed the maximum drive current).

Most DIY LED designs achieve low enough junction temps that the LEDS will retain >90% of their original efficiency before they end up getting replaced by newer emitters. Based on all that and taking efficiency and bud size into consideration, I run them all at 700mA and aim for junction temps of 50-55c.
 
brotherjericho

brotherjericho

Well-Known Member
^^ Thanks.

Well, everything is ordered. Total, including shipping, is $525. Yikes! Could have purchased two Hans Panels or one Area51 SGS-160 (more wattage!) for that price but I could not have the several advantages of my DIY: separate control of each 30 piece section, as well as control of reds in each section, footprint tailored to my grow needs, and finally, passive cooling. At least I hope I get there on the last one, I have 1230 in^2, running ~116w, approximate efficiency of 37% (could be better, low balled it) since I am running Cree XT-E whites, XP-E reds, and Rebel ES deep reds all at 700ma max. So using 37%, thats roughly 73w to dissipate, at 16.84 in^2/w. Think I'll be good?
 
J

jcmjrt

Well-Known Member
brotherjericho said:
You should be good since you are using all high quality LEDs (less heat, more light!).

I'm diying a new LED strip and part of the order has arrived. I have the heat sink/manifold system done and when the rest of the LEDs and drivers get here, it won't take long to be up and running. The flowering is going great right now but with the extra light...well, I'm hoping for even better. :)
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turnip brain

turnip brain

Active Member
jcmjrt said:
You should be good since you are using all high quality LEDs (less heat, more light!).

I'm diying a new LED strip and part of the order has arrived. I have the heat sink/manifold system done and when the rest of the LEDs and drivers get here, it won't take long to be up and running. The flowering is going great right now but with the extra light...well, I'm hoping for even better. :)
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Hey, if any different than just fan/tube, i.e. actual manifold to tubes, please post pics of your heatsink/manifold system. Thanks.
 
J

jcmjrt

Well-Known Member
turnip brain said:
Hey, if any different than just fan/tube, i.e. actual manifold to tubes, please post pics of your heatsink/manifold system. Thanks.
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http://shop.stevesleds.com/Biocube-29-Gallon-LED-retrofit-kit-Oceanic-AND-Coralife-Biocube-29-Gallon-retrofit-kit.htm


I don't have pics but it looks like what you see at stevesleds.com. I've cut them pretty closely and then JB welded the manifold to the two tubes whereas steves looks like he precision cut and then riveted the parts together and my tubes are only about 1/2 inch apart from each other.
 
brotherjericho

brotherjericho

Well-Known Member
jcmjrt said:
http://shop.stevesleds.com/Biocube-29-Gallon-LED-retrofit-kit-Oceanic-AND-Coralife-Biocube-29-Gallon-retrofit-kit.htm


I don't have pics but it looks like what you see at stevesleds.com. I've cut them pretty closely and then JB welded the manifold to the two tubes whereas steves looks like he precision cut and then riveted the parts together and my tubes are only about 1/2 inch apart from each other.
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I was thinking about going with an aluminum DIY heatsink, but I had to go massive to get passive cooling. I could do it, find some 3" angle (basically 12 ^in2 per in length!) but the prices started to exceed the cost of a heatsink cut to length from Heatsinks USA. With fan cooling, sure, but I want to reduce the amount of wiring I'd have to do plus reduce potential failure by 1-2 factors (number of fans) and make my grows more stealthy. Sometimes I'm gone for a few days, fan goes out...all sorts of bad stuff might happen. But that's just my thought process.

I do like the idea of that fan on the end of the tubes. Each one has 5 in^2 per in length, so you get decent cooling if you don't overdue it with the LEDs. But add that fan on the end, could be nice. Wonder how quiet it is? Might look at something similar for my veg tent should I go all LED.
 
turnip brain

turnip brain

Active Member
SupraSPL

SupraSPL

Well-Known Member
brotherjericho said:
I have 1230 in^2, running ~116w, approximate efficiency of 37% (could be better, low balled it) since I am running Cree XT-E whites, XP-E reds, and Rebel ES deep reds all at 700ma max. So using 37%, thats roughly 73w to dissipate, at 16.84 in^2/w. Think I'll be good?
Click to expand...
Back in the day when KNNA made his recommendations the lamps were about 26% efficient and most of us were getting the emitters from him. So he offered us a one size fits all starting point of 21sq in/watt for passive cooling, but he was referring to dissipation wattage since all of our lamps were about the same that made for easy math.

I adjusted that number down to 17sq in/watt since we are in the 40% range now, but that number still refers to dissipation wattage. So based on that, for 116 dissipation watts you would need 1972 sq in to get near a 50c Tj target. Sorry to be the bearer of bad news!
 
SupraSPL

SupraSPL

Well-Known Member
brotherjericho said:
Total, including shipping, is $525. Yikes! Could have purchased two Hans Panels or one Area51 SGS-160 (more wattage!) for that price but I could not have the several advantages of my DIY: separate control of each 30 piece section, as well as control of reds in each section, footprint tailored to my grow needs, and finally, passive cooling.
Click to expand...
With all due respect to area 51, one of the best lamps out there I am sure and very well thought out to provide a marketable solution, your lamp will perform better IMO. Area 51 flowering mode dissipation wattage should be ~120w because of 15-20% driver losses and 50% ac-dc conversion losses to power 2 fans so your dissipation is about equal. The XPG outdoor white will not compare to your XTE WW, your XPEs are P3 bin, your SPD is better and you are going lenseless which should nab another 10% and provide better adjustability for your canopy. Finally, your Tj will be much lower which is critical for the reds.
 
brotherjericho

brotherjericho

Well-Known Member
SupraSPL said:
Back in the day when KNNA made his recommendations the lamps were about 26% efficient and most of us were getting the emitters from him. So he offered us a one size fits all starting point of 21sq in/watt for passive cooling, but he was referring to dissipation wattage since all of our lamps were about the same that made for easy math.

I adjusted that number down to 17sq in/watt since we are in the 40% range now, but that number still refers to dissipation wattage. So based on that, for 116 dissipation watts you would need 1972 sq in to get near a 50c Tj target. Sorry to be the bearer of bad news!
Click to expand...
Oh, so its still just total wattage of all the LEDs, and not difference in light energy watts? So 116w, the total of my LEDs, is what I am supposed to use, and not that number times .63? I was wondering about that...
 
brotherjericho

brotherjericho

Well-Known Member
Went back and read your thread on DIY LED 220w, I see now, had this totally mixed up. Oh well, still like the area for the way I want to layout my LEDs...could have gone slightly smaller but this is still going to be a good size for my flower tent. I will actually have each 30 piece section (~58w) on an 8.46"x10" heat sink (so 2 heatsinks), will one 120mm fan per section be fine? Will building some type of enclosure be necessary, since the fan will obviously not cover the whole 8.46"x10?

Thanks!
 
SupraSPL

SupraSPL

Well-Known Member
I use those for veggin and figured them to be good for 40-45 watts each with passive cooling. I end up with heatsink temps of about 95f. You could give it a go and see what temps you are getting with 1 fan on each. They can also benefit from the circulation fan if you have one in the room.
 
R

RainerRocks

Active Member
brotherjericho said:
What do you folks think about these? 82 deg reflectors, no lens, so no loss of light but better than the 120-130 deg viewing angle of the LEDs.



http://www.mouser.com/ds/2/229/Lisa2-XP-E-Ledil-datasheet-195139.pdf

It says for Cree XP-E, but are the XT-Es that much of a difference that it would not work?
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When I bought my rapidled lenses I also asked rapid if the XP-E's lenses would also work for the XT-E's (being I ordered both ) and they said yes.

I never got the chance or time to put them on but I did try and see if they would fit and they did.

That being said you better email mouser because they might be different than my lenses.
 
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