Building New Panels - Sharing the Process

[tenthirty]

Here is a good example of extreme plant morphology.
https://www.icmag.com/ic/showthread.php?t=250841&page=5

Will his plants produce....yes.
Will they be dank.......yes.
Will they be what he wants or express their full potential????

Being a cheep lazy stoner hating trimming,
I got into this because I wanted to grow budsicles on the least electricity possible.

Cut it down, trim a few leaves....done!!

What proper spectrum brings to the table is better health and consistent morphology.
The light needs to be as consistent and homogeneous as possible,
and as harmonic rich as possible.

In an ideal world all the diodes would produce the same spectral curve providing for very consistent light at any time/place in the growth chamber. Thus my comments in his thread.

Everything is a compromise????

 

[guvoo]

Guvoo has 17 LEDs in his snappy design.

if you need more leds it will be no problem.
the fan/heatsink combo is calculated for 50W. thats about 20 white Leds and 4 red leds at 700mA. placing is the problem here.
and the fan circuit needs also a little modification.

the Spectrum is good for veg and flower. the only change I made is in the blue range

4 cool white
1 blue 465nm
gives a better spread in this range

some stuff on this

http://e-archivo.uc3m.es/bitstream/...ez_Final Project 2012_Aalto University_LE.pdf

and here you can play with led and see what happen to the spectrum.

http://buildmyled.com/custom-led-strip/

 

[rrog]

Some pretty amazing resources here. I'm grateful for the lessons. Thank you.

tenthirty- You advocate less blue in flower. To clarify, the example of extreme plant morphology used the WW+ NW+ CW in a 2:2:1 ratio, and you'd attribute the blue to that. I couldn't argue that, as I normally veg and flower with a Ushio HPS, no blue enhancement.

I supplement with a quality reptile MH lamp for UV-b as a side note.

guvoo- So that would handle 50W. Even better. I want to cover a 4x4 footprint, 3-4 plants. Rives mentioned that KNNA feels we should look at 30W per sq. ft. I'd need 8 of the unit you originally built? Am I understanding this correctly? I think those great units were 30W each?

 

[WeedIsGod]

What a cool link guvoo. Thanks.

WW+ NW+ CW in a 2:2:1
That looks like a veg panel to me.

CW+NW+WW+625+660 in a 1:1:1:1:1

WW:NW:630:660
9:3:1:2

 

[rives]

Rrog, bear in mind that you could easily scale that design up to get more into the range that I was talking about earlier. I don't recall Guvoo ever discussing why he went with that low of wattage, but personally, I would want to get coverage of a coverage of 1.5-2 square feet per unit if for no other reason than the simplicity of hanging them. Take a look at the following 100-200 watt offerings from California Lightworks, or the now obsolete ES165 from Lumigrow.

http://californialightworks.com/

https://growershouse.com/lumigrow-es165-led-grow-light

 

[rrog]

I see they're looking at 50W psf at california lightworks.

So clearly a 200W panel is possible, or would it be better to have two 100W boards, maybe?

Those are great images.

 

[tenthirty]

tenthirty- You advocate less blue in flower.

Yes and no........
Too much either way red or blue and limited spectrum causes the plant to be malformed to one degree or another, possibly to the point of strange growths on the plant.

What seems to be more important is a consistent full spectrum within the growth chamber.
Then you can steer the plant with shifting the spectrum red or blue,
but by using discrete colors of leds the consistency of light is compromised.

You can get away with some lack of consistency, but how much?????

FYI,
I will probably never use a discrete color of led again in something that I build, that is unless we're talking about remote phosphors.

 

[rrog]

I can see the logic of whites for sure. guvoo commented elsewhere that the blues had a wider field and that needed to be accounted for.

If we're shooting for 30W+ psf, I need ~500W for a 4x4 footprint. So how to divide that up. If I assumed 4 plants in a 4x4 area, I should look at 4 panels, each with at least 150W.

Seems like that should spread out the coverage?

Is it difficult to shift the spectrum red to blue? I wonder if I should be looking at one panel with a total of 175W, where I can somehow "dim" some to accentuate red or blue. Since one or the other will be dimmed, maybe ~150W effective output? Am I picturing this process correctly?

 

[rives]

If you want the capacity for each in the same fixture, you can power the reds and the blues with dedicated, dimming drivers so that each one can be tweaked to whatever level you want. This is what the Lumigrow design does.They drive the reds and the whites together, but independently of the blues.

While I appreciate tenthirty's point on light consistency, I think that with a sufficient number of chips and the correct lensing that there is enough overlap to minimize the problem.

 

[rrog]

To your point, Rives, if I were to use more LEDs, more spread out across a 175W panel, there could be enough overlap. Both reasonable perspectives.

Question- if you had the aforementioned WW+ NW+ CW in a 2:2:1 ratio, is it reasonable that you could dim the bluer of the three or the redder of the three. Or can we only adjust blue / red if we have discrete LEDs for that wavelength?

 

[rives]

You can dim anything independently as long as it is powered by it's own dimming driver.

 

[rrog]

Thanks R-

From another LED Builder, Stardustsailor:

-4 x cool whites ( 6000-9000°K )
-4 x neutral whites ( 4500-6500°K )
-12 x Warm Whites ( 2500-3500°K )
-4 x Red 620-640 nm ( 630 nm )

Seems like you could dim the reds for veg, and dim some CW for flower?

Next- is there a thought on LED wattage vs penetration? Is a 175W panel full of 3 watt better or fewer but higher wattage?

 

[Goldy]

depends how your gonna do them man, scrog ought to be great with 3w to 5w but id be tempted not to go to 10w..
if your goin for tall trees youl want higher wattage. you could always just grab some and dim them if theyre too intense. be the first person to chuck 1k of leds in a tent lol..if you could pull it off itd be siick. just given me an idea haha

p.s. im not certain but i imagine you could go hard and use high watt leds even fairly close up..just youd have to be perfectly dialed in with your spectrum or youll experience bleaching and other mutations. again pretty sure this is due to unequal hormone/chemical production causing an inbalance..some regulate breakdown and protect chlorophyll etc.

 

[rives]

First, I should note that the contributor that you referenced above has a distinctly different take on workable spectrums than most. From what I have read, he is very opposed to 660nm light - empirical evidence refutes this, as far as I'm concerned. Look in my albums to see the result of 660nm light.

The power question is another bowl of worms. Detecting a trend here? The lower powered LEDs are more efficient. The higher powered ones, with equivalent lensing, have better penetration. The lower powered ones, scattered evenly over the canopy, give an all-encompassing light source with no shadowing. The higher-powered units are infinitely easier to build with. When I built the Hybrid fixture, I used (41) Osram Golden Dragon Plus LEDs per 4" x 22" heat sink. If my current experiments work out the way that I hope, I will eventually change out each of the (4) PL-L lamps with (5) NW LED's driven at around 13-15 watts. I used 10 watt chips on the VolksLED, and with a 4" x 22" envelope it did an amazing job at vegging a 30" x 30" screen. I wouldn't expect it to do as well over taller subjects, but it is currently over the top of two bushes that are 20"+ tall and they are some happy girls.

Read, read, read, then pay your money and take your choice!

*edit* I just read Goldy's post and would add this - I've bleached the shit out of some plants with my ES330 running at 12"+/-. For the last several weeks, I've been running a 40w cw within 4" of the tops of two small plants, and haven't seen any problems. I'm starting to believe that whites won't bleach.

 

[tenthirty]

Question- if you had the aforementioned WW+ NW+ CW in a 2:2:1 ratio, is it reasonable that you could dim the bluer of the three or the redder of the three. Or can we only adjust blue / red if we have discrete LEDs for that wavelength?

That would work.

I'm starting to believe that whites won't bleach.

Now that is interesting!!

 

[WeedIsGod]

Dimmed LED's use the same amount of energy as undimmed, don't they? I'd rather get the spectrum right for full cycle, or have certain LED's on a different on/off.

 

[rives]

Dimmed LED's use the same amount of energy as undimmed, don't they? I'd rather get the spectrum right for full cycle, or have certain LED's on a different on/off.

No, they do not. The voltage & current goes down to dim them, thus the wattage drops off.

 

[rrog]

Rives- Generally I'd be more interested in penetration. Not as interested in efficiency.

So for a 150W panel, using 10W LEDs:

WW 6 Three dim-able?
NW 6
CW 3 Three dim-able?

Given that some are dimmed at any point, Maybe I have an effective output of ~125W per panel

4 of these over a 4x4 area = 500W, or 31W psf in flower. That should do it?

 

[tenthirty]

Speaking of extreme plant morphology.
https://www.icmag.com/ic/showpost.php?p=5408496&postcount=15

So for a 150W panel, using 10W LEDs:

WW 6 Three dim-able?
NW 6
CW 3 Three dim-able?

Given that some are dimmed at any point, Maybe I have an effective output of ~125W per panel

4 of these over a 4x4 area = 500W, or 31W psf in flower. That should do it?

Ok, so now you have a ball park. It's time to pick the players.

What heat sinks will you use?
What drivers will you use?

 

[rives]

Remember, you are going to need a separate driver for each dimming group. So for your example, unless you could group the (3) undimmed ww with the (6) undimmed nw, you would wind up needing a total of four drivers per fixture.

Now for another twist - 10 watt chips don't necessarily pull 10 watts. You need to look at the curves for whatever components you are thinking about and see how hard they can really be pushed. This is impacted tremendously by how efficient your heat extraction is. For instance, the Golden Dragon's that I am using are considered a 1 watt chip. At their normal recommended current level, they run at about .8 watts. I'm pushing them at about 1.5 watts with temperatures about 10-15 degrees over ambient. Your cooling design is of paramount importance.