Discussion of the pragmatic application of LED's

[PetFlora]

"Many years back I was doing side by sides with first and second generation LEDs. "

Yes I remember it well. Got a lot of reliable information from you.
Mahalo for the new links, I'll be busy for a while.

Not as long as I thought.
I'll go back and read the citations in a bit.

The first link is excellent.
Good science there!

The second is obviously grinding an axe and appears to be produced by their marketing department.
Their references are informative and accurate, but their conclusion are not.

As this thread is about pragmatic use we can conclude that what works, works.
And, the proper ratio of narrow bandwidth red and blue light grows excellent cannabis.

I have a side by side going now pitting a 120W. White LED "corn light" against a 100W., single, 44 mm. chip, R:B 4:1 DIY lamp.

I do not have the means to measure CO2 uptake, but I can easily measure water use.
I'm pragmatic, I weigh them.

In the first week, the 6000K White leds are lagging the 2 color chip by about 30%!
After a month I'll look at things like leaf thickness, fragility, blah, blah.

I'll keep y'all posted.

Why would you opt for 6000K? That's way too much blue. Our girls thrive on ~ 15% blue. A 4000-4500K would provide adequate blue with plenty of green and red

 

[PetFlora]

Here's a most helpful tip I learned back in the day when I first figured out blurple ain't where its at

[FONT=Arial, Helvetica, sans-serif]This is inside info from 2012, in response to a query I made on IC

As one can see, the CREE Neutral White (I call it 'Goldilocks', because it's almost 'just right'

) has a RSPD that still allows nearly ~25% of its total power in the blue range (and plants only really 'need' ~8-10%), and more than 1/3 of which (i.e. the area under the curve) is over ~580nm or so (which has a Photosynthetic RS of over 90%!) - which is much better than even your typical 'Enhanced HPS'.

Couple that with strong white light (green-response chlorophyll extending throughout and deep into leaf structures, with a net effect at or near that of the (mostly) surface-level blue and reds), which also takes care of most of the ~660nm+ you actually need for photomorphogenesis - and you can get by with 630nm reds just fine.

(i.e. 630nm red is ~95% of the PSR of 660nm, AND they currently still have ~20-30% greater radiometric efficiency - as well as being cheaper than the deep reds - so there's more 'bang for the buck'):

Something like that would probably meet the needs of ~95% of today's growers.

[/FONT]

 

[Weezard]

"Why would you opt for 6000K? That's way too much blue. "

Tell me about it.

It was an unexpected gift from a friend.
He had a get rich quick scheme to make LED retrofit bulbs to replace 400W. halides.

Did not do his homework.
Just sent me one from his first bulk purchase and asked me to test it.
Figured the too blue might be welcome in early vegs, so did a side by side for him.

It can not even stand against my 9 year old, 56W., R:B "brick".

After reading the links here, I dusted it off to see if proximity would provide enough intensity to seedlings to to make paying for the green bands worthwhile.

Does not matter how much I doubt it.
Don't really know until I try it, yah?

Aloha,
Weeze

 

[Tri_Cho_Me]

I'm an LED grower! Advanced Platinum Series P450, some two supplemental LED bulbs for just outside the P450 footprint.

I like LED'a because they are energy efficient, run cooler, and the LED's themselves will never dim. They put out the same light on day 1 as on day 1,000.

Tri_Cho_Me

 

[Weezard]

"will never dim. They put out the same light on day 1 as on day 1,000.

That would be almost true at 24,000 hours.
They actually do dim eventually, especially if they run too hot.
After 50,000 hours they can be down as much as 20%. But still be usable.
Beats replacing HPS bulbs every cycle.

I run mine at 90° F. and they have been in service, counting down time, for ~54,000 hours and have not lost 5% yet.
During that time, they used about 3,024 Kwh. @ $ .40per. so cost me a tad over $1200. US.
Had I used 400 W. HPS, it would have cost me ~ $9,677, not counting the cost of bulb replacement, or cooling.
That's why I use leds.
Aloha,
Weeze

 

[Tri_Cho_Me]

"will never dim. They put out the same light on day 1 as on day 1,000.

That would be almost true at 24,000 hours.
They actually do dim eventually, especially if they run too hot.
After 50,000 hours they can be down as much as 20%. But still be usable.
Beats replacing HPS bulbs every cycle.

I run mine at 90° F. and they have been in service, counting down time, for ~54,000 hours and have not lost 5% yet.
During that time, they used about 3,024 Kwh. @ $ .40per. so cost me a tad over $1200. US.
Had I used 400 W. HPS, it would have cost me ~ $9,677, not counting the cost of bulb replacement, or cooling.
That's why I use leds.
Aloha,
Weeze

Hell ya man. Thank you for replying kindly and providing additional thought and opinion. Some others on here aren't as generous.

What LED's are you running?
What do you think of COB LED's?
If you had to buy a new light today, what would you get?

Tri_Cho_Me

 

[Weezard]

"What LED's are you running?

Browse through my albums. all my arrays are DIY but there are choke pictures.
I answer picture comments.

What do you think of COB LED's?

Best way to fly. Not a fan of white led cobs though.

If you had to buy a new light today, what would you get?"

"had to buy" Nope.

Had to replace?

Different story.
Actually my ancient lights are performing well, but I'm building a couple with modern tech anyway.
It's gotten so easy and inexpensive to DIY now that I could not resist.
Will be posting pics of the new build when my thermal grease arrives.
Slow boat, China, could be a while.
I have documented old builds on another site.
It would be discourteous to point at it here, but if you google "Calling out to Weezard for led advice" it will probably pop up.

Mahalo fo' da kind words.
Aloha,
Weeze

 

[PetFlora]

Weez

How about making one light using a small CW or NW CoB (~ 50w) in the center then surround it with various diodes to compare against your non white light

This is what Amare Technology does with his CoB Hybrid designs. I now have 3 of them; the original SE 220 (with warm white CoBs), the replacement SE 250 (with cool white CoBs), and getting ready to hook up his Pro3 which is 300w. Not sure which spectrum CoB, but likely the cool white.

The Pro 3 is replacing my 2.5 year old BML SPYDR 600 (~ 360w, pre CoB). Back then I contacted BML and convinced Nick that if he let me select the spectrums I could provide him with a light for both veg and flower, which would garner him a lot more sales. He agreed and collaborated to select the diodes. It is 90% mix of cw, nw, and ww chips + some 450s and 625.

The design is fantastic, but the execution leaves a bit to be desired, as the 6 @ 4ft bars are designed to slide along the spine to either use as 2 x 4 or spread to 4 x 4. During veg collapse for more light to the babies, then spread to 4 x 4 for the mature plants. Great idea, not so good execution. Anyway it's for sale if you know anyone


View attachment 384115

 

[Weezard]

I do get asked to build arrays often, and might even do so if I run out of beer money.
Fortunately, I'm still solvent enough to enjoy being retired.

I'd be happy to send these folks to you, but that design would not fly here.

Why not?
Simple economics.
That level of power consumption, at our power costs, makes growing more expensive than buying, yah?
I'm not a cheap-skate, I'm a broke-skate on anti-social in-security.

Aloha,
Weeze

 

[PetFlora]

Just paid my bill. I was running 2 ac systems (one just to keep the room cool enough for buds to swell) + 3 lights

The SPYDR , the Amare se 220 (220w) and the SE 250, which I believe is rated at 275w + the pumps running every hour + air stones, large circ fan + the rest of the house

Last month it was $295. This month due to cooler weather it dropped to $222.+ for 1975 kWs

I did not total weight from all 3 but well over a pound. That buys the lights and the electric with bunch left over

@ $10/g let alone $15, which is not unreasonable for this quality.

This part of the haul (see picture) came from the se 250 + a fair amount of larf that will make some sweet butter


View attachment 384264

 

[ThaMagnificent]

Hey Pet,

With your Amare and Veg Bloom did you need to add in any extra Cal/Mag?

 

[Weezard]

State of the art

State of the art

"Last month it was $295. This month due to cooler weather it dropped to $222.+ for 1975 kWs

I did not total weight from all 3 but well over a pound. That buys the lights and the electric with bunch left over "

You are paying ~1/4th what we do for power.
Must be nice.

My cabinet easily holds 15 plants.
I use less that 200 Watts of bi-color leds total for vegging, starting, and cloning.
In 60 days, that's 192Kwh. Roughly $79 for 2 months
That include the fans and I need no AC, in the tropics.

Here's a snap of the new light. Single chip, 44mm., 100W., 660nm,. 460nm., 4:1 ratio.


Building it is as easy as legos.
The main fan that comes with the 'sink is 12v. but the chip runs on 24v..
Had a 12v. wall-wart kine supply ready, but if it were to fail, my $50 chip would be toast.

So, I tied the power supply to the assembly and slapped a 12v. muffin fan on it.
I run the fans in series across the 24v. supply. Should it fail, I have a replacement on hand and no damage done.

With the 2 fans, and throttling it to 60Watts total input, it runs at 90° F. with an ambient of ~82° F.
Next to my 10 year old 56W, array, it is impressively bright.


It was way too easy to assemble.

Had planned to do a thread, but when I reached for my camera, it was almost done.
Meh, any English schoolboy could assemble one in an hour so there's really no need for a tutorial.
I'll do a walk through, on demand, and will be happy to provide a list of the parts needed if anyone cares.

One chip, $48.
One 24V. 4.5A. power supply. $20.
One spiffy, heat sink w/quiet fan. $35
One 12v. muffin fan. On hand. Or about 3 bucks.
Only 2 solder connections. Or, you could use clip leads if you don't speak solder.

Build time?
About an hour total if you are too stoned to remember what you are doing. (That would be me.)

Cost about a buck a Watt.
It is already putting that white light, LED, corn light to shame.
I am extremely happy with the results so far.
Am now assembling the dual bay heat sink designed to hold 2. 44mm., 100W., chips.
Using one all red, and one all blue chip, I will hang it from a central cord and spin it for color blending.

Will adjust the output ratio for morphology control only because I use sunlight for flowering and do not need a "bloom ratio".
Aloha,
Da purple Weeze

 

[PetFlora]

Hey Pet,

With your Amare and Veg Bloom did you need to add in any extra Cal/Mag?

Yes. I vegging without added CaMg, but the plants were very spindly.

Once I moved them to the main leds I started adding 10+ ml of CaMg and both clones have firmed up.

However, one not as much as the other, BUT, both were in the same bubbler, and their roots hammocked. In separating them, one suffered a lot

 

[ThaMagnificent]

Yes. I vegging without added CaMg, but the plants were very spindly.

Once I moved them to the main leds I started adding 10+ ml of CaMg and both clones have firmed up.

However, one not as much as the other, BUT, both were in the same bubbler, and their roots hammocked. In separating them, one suffered a lot

10mL/gal?

 

[PetFlora]

10mL/gal?

I use Emerald Harvest CaMg @ 5ml/gallon