^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^Thanks for the pix!
This is getting more interesting each day!
P.S. Heatsinks received, LEDs/drivers shipped yesterday.
Nice..almost there and time to build...weeeeeeeeeeeeee
Good Luck
Building a Home Made LED
- Thread starter tenthirty
- Start date
Nice..almost there and time to build...weeeeeeeeeeeeee
Good Luck
Thanks vukman! it will be a while for everything to reach here, I think just in time for flowering!
If reds and deep reds are dimmed with the same driver, using 3W LEDs @~600mA, an interesting driver would be the MW ELN-60-48D dimmable driver (24-48V, 0-1,3A adjustable, 62W, dimming is voltage controlled), with two of these, one for red another for blues, in two fixtures (2 separate heatsinks) 120W would be achievable easily and cheapily by running each fixture color string (~14 LEDs) in parallel with each driver.
Add a couple potentiometers and a 10V wallwart to control the dimming and you're done...
140W using 2 LPC-60-1050, 1 LPC-60-1750, 10 XM-L, 24 XP-Gs including heatsinks would be about $400, or $2.85 per watt
120W using 2 ELN-60-48D, 56 3W red/deep red/royal blue LEDs (from Aliexpress) including heatsinks would be about $250, or $2 per watt.
sounds really tempting!
If reds and deep reds are dimmed with the same driver, using 3W LEDs @~600mA, an interesting driver would be the MW ELN-60-48D dimmable driver (24-48V, 0-1,3A adjustable, 62W, dimming is voltage controlled), with two of these, one for red another for blues, in two fixtures (2 separate heatsinks) 120W would be achievable easily and cheapily by running each fixture color string (~14 LEDs) in parallel with each driver.
Add a couple potentiometers and a 10V wallwart to control the dimming and you're done...
140W using 2 LPC-60-1050, 1 LPC-60-1750, 10 XM-L, 24 XP-Gs including heatsinks would be about $400, or $2.85 per watt
120W using 2 ELN-60-48D, 56 3W red/deep red/royal blue LEDs (from Aliexpress) including heatsinks would be about $250, or $2 per watt.
sounds really tempting!
luvdemshrooms
Member
Thanks for the input, but the Cree folks and a couple electronic engineers assure me that you can read 125c on the thermal pads adjacent to the LED before panicking. All recommended lower temps than that for LED longevity. 100c at those pads seemed to be the general consensus.
At 2A after 18hrs my test unit only hit 78C.
My inductors are due today. As a pleasant coincidence, I have two nearly identical clones. I'll test my sample on one, with the other under my MH. I should know in a couple weeks if there's anything to this. If so, I'll build my 3 footer with a thread to document it, and then a grow log.
Thanks all who inspired me. While building LED lights for a living is fun, this was far better.
Please post here when you start the grow log!
Why did you use that diamond pattern? IMHO that wastes heatsink real state at the center, wouldn't an 4x3 array pattern dissipate better as every LED will have its own space?
luvdemshrooms
Member
My original intent was a hex pattern to match the hex stars. Alas, I failed.
I chose the pattern for the same reason I chose the 10" wide heat sink. I wanted the light to hit the plant from many angles to increase penetration. A circle or square pattern would have done the same. I went with the hex because I thought it would look cool. Even then I wound up shifting everything a bit so that when I drilled and tapped the holes, I would miss the cooling fins on the other side.
If I could have found a finned heatsink ring, about 12" in diameter, I'd have used that. I could have one made but the expense didn't seem worth it to me.
I chose the pattern for the same reason I chose the 10" wide heat sink. I wanted the light to hit the plant from many angles to increase penetration. A circle or square pattern would have done the same. I went with the hex because I thought it would look cool. Even then I wound up shifting everything a bit so that when I drilled and tapped the holes, I would miss the cooling fins on the other side.
If I could have found a finned heatsink ring, about 12" in diameter, I'd have used that. I could have one made but the expense didn't seem worth it to me.
luvdemshrooms
Member
Maybe someone can help. I've read the forum rules. They say nothing about the ability to edit a post, which I seem to lack.
What's the deal?
What's the deal?
You must have at least 50 posts before you will be able to edit your posts and do much more other things.
L.E. This should be useful, I guess http://www.icmag.com/modules/Benefits/
luvdemshrooms
Member
Weezard, why wouldn't combining CW + WW + NW be a better option than actinic R/Bs?
To me, actinics are like digital music reproduction, which provides an incomplete sign wave, and therefor less than full bodied sound. D2A converters cost many thousands of dollars attempting to fill in the missing sign wave gaps, and yet they fall short of analog playback
Whites have broad RGB bands with smooth transitions in between. The palnt can decide how much of the 'tweeners it needs, but if they aren't there...
To me, actinics are like digital music reproduction, which provides an incomplete sign wave, and therefor less than full bodied sound. D2A converters cost many thousands of dollars attempting to fill in the missing sign wave gaps, and yet they fall short of analog playback
Whites have broad RGB bands with smooth transitions in between. The palnt can decide how much of the 'tweeners it needs, but if they aren't there...
Now the letting the plant decide what it needs is one thing but locate its peaks and valleys and then putting the right spectrum to hit those however would make sense in my head. Why offer a ton of tweeners if you can have the exacters that the plants have been known to uptake peak levels on.
I still want to add some cw ww and nw to a r / b panel versus one without and see how that grows.
I still want to add some cw ww and nw to a r / b panel versus one without and see how that grows.
luvdemshrooms
Member
If you use white (any kind of white) you need more lumens to achive the same energy provided by the narow band leds.
But when just narow band leds are used, it is very likely that some strains to be out of sync with the wave lengths of that leds so even the power is increased, the photosinthesis will not be made with maximum eficiency.
It would be very useful to have some kind of variable wavelength leds (depending on the forward voltage fir example). But this is just fantasy for the moment.
If the leaves seems black on some blend light of red and blue , this does not mandatory means that the photosyntethis process is optimal, but rather that the used liht does not contain the any component closed to the green colour.
If you grow the plants on a obscure room (with black walls, and everything is black) under blue and red leds, the green of the leaf will apear always as black. But if in that room you introduce objects with different colours , the green will became more or less visible, depending on how much light is reflected and refracted by sorounding objects.
Some calculation could be made to achive a theoretical maximum eficincy, but as we all know, it's a big difference between theory and real facts.
I personaly use a mix of red , deep red, blue, royal blue, cool white, warm white abd extra cool white (20000K) on my DIY LED panel and I am very satisfied with the quality of my buds.
My point is that is now a single way to build a led panel and the results could be similar with diferrent setups. I bet you can get very good results with a 1000w panel giving a footprint of 4sf even if that panel contains only green leds (which can sound a little bit crazy).
But when just narow band leds are used, it is very likely that some strains to be out of sync with the wave lengths of that leds so even the power is increased, the photosinthesis will not be made with maximum eficiency.
It would be very useful to have some kind of variable wavelength leds (depending on the forward voltage fir example). But this is just fantasy for the moment.
If the leaves seems black on some blend light of red and blue , this does not mandatory means that the photosyntethis process is optimal, but rather that the used liht does not contain the any component closed to the green colour.
If you grow the plants on a obscure room (with black walls, and everything is black) under blue and red leds, the green of the leaf will apear always as black. But if in that room you introduce objects with different colours , the green will became more or less visible, depending on how much light is reflected and refracted by sorounding objects.
Some calculation could be made to achive a theoretical maximum eficincy, but as we all know, it's a big difference between theory and real facts.
I personaly use a mix of red , deep red, blue, royal blue, cool white, warm white abd extra cool white (20000K) on my DIY LED panel and I am very satisfied with the quality of my buds.
My point is that is now a single way to build a led panel and the results could be similar with diferrent setups. I bet you can get very good results with a 1000w panel giving a footprint of 4sf even if that panel contains only green leds (which can sound a little bit crazy).
Succinct and to the point
Succinct and to the point
The short, answer:
"Why offer a ton of tweeners if you can have the exacters that the plants have been known to uptake peak levels on?"
Mahalo Medmaker.
Weeze
Succinct and to the point
The short, answer:
"Why offer a ton of tweeners if you can have the exacters that the plants have been known to uptake peak levels on?"
Mahalo Medmaker.
Weeze
luvdemshrooms
Member
So basically, personal preference?
Or am I misunderstanding?
Or am I misunderstanding?
Only predominantly green.
Only predominantly green.
@hempfield
"If you grow the plants on a obscure room (with black walls, and everything is black) under blue and red leds, the green of the leaf will apear always as black."
That's sounds correct, but it is not.
Were the plants a pure green, it would be so.
They are not.
They are a blend of colors.
I was half kidding with the absorption thing.
Thought it obvious that absorbing the light does not necessarily mean using that light for photosynthesis.
The point was, reflected light does not get used at all.
Ya bought it, then threw it away.
"Hey! I bought you kids a ton of green light, and it's still on the plate.
Eat yer greens ya little ingrates! Plants in China are starving!"
@petflora
I'm guessing your electricity rates are more reasonable than mine.
I just can't afford, a smorgasbord, that gets ignored.
Aloha, y'all
Weeze
Only predominantly green.
@hempfield
"If you grow the plants on a obscure room (with black walls, and everything is black) under blue and red leds, the green of the leaf will apear always as black."
That's sounds correct, but it is not.
Were the plants a pure green, it would be so.
They are not.
They are a blend of colors.
I was half kidding with the absorption thing.
Thought it obvious that absorbing the light does not necessarily mean using that light for photosynthesis.
The point was, reflected light does not get used at all.
Ya bought it, then threw it away.
"Hey! I bought you kids a ton of green light, and it's still on the plate.
Eat yer greens ya little ingrates! Plants in China are starving!"
@petflora
I'm guessing your electricity rates are more reasonable than mine.
I just can't afford, a smorgasbord, that gets ignored.
Aloha, y'all
Weeze
Less is more.
Less is more.
It's not about longevity so much as efficacy.
The cooler your junction, the more photons per watt.
Always shoot for the "sweet spot".
A.
W.
Less is more.
It's not about longevity so much as efficacy.
The cooler your junction, the more photons per watt.
Always shoot for the "sweet spot".
A.
W.
luvdemshrooms
Member
Gotcha. So, the data sheet puts me at roughly 90% at the temps I'm running.
I'll try a fan and see what happens.
I just happen to have a couple. It's good to be a collector of bits and pieces. Sometimes.
Was it your post where the mention of water cooling came up?
I'll try a fan and see what happens.
I just happen to have a couple. It's good to be a collector of bits and pieces. Sometimes.
Was it your post where the mention of water cooling came up?
luvdemshrooms
Member
I wonder if your way of looking at this revolves around keeping your electric bill as low as possible, where as I want a very bright light (in the correct wavelengths) and am willing to pay a bit more to do so.
