Bridgelux EB Series Build

Dachem2010

Well-Known Member
Not you humble to me it sounds like your researching it all depends on if the lamp uses quartz envelope as normal glass blocks uv spectrum so ceramic metal halides will definitely have some as they use that quartz so they can burn at a higher temp., uvb leds are horribly inefficient and very expensive and can't used something with UVC as that's very damaging to all biologicals
 

Randomblame

Well-Known Member
I think he is referring to a university study:

"UV-B RADIATION EFFECTS ON PHOTOSYNTHESIS, GROWTH AND CANNABINOID PRODUCTION OF TWO Cannabis Sativa CHEMOTYPES."

What they forget to mention is that that test used a very high dose of UV to reach that maximum result. 72W/m2 of UV bulb. With a pretty much linear relation between UV light intensity and THC delta (pun intended). So if you use a lot less then the effect is a lot less too.

Now what would happen if you add 72W of regular light per m2? You might get say 20% more yield. Not sure I'd take a THC increase over a yield increase.

Plus I wonder if the plants don't yield less because of the UV. If you make them struggle to survive the UV for a THC response, wont that detract from actual yields. Don't remember if the article mentioned something about that.
See, now that does not sound like something "beneficial" to me. Its obvious that UV is damaging to plants - and as Wietefras points out, gains in potency would likely be offset by yield loss. I've said before, the evidence *is* compelling, but IMO, it falls short of being convincing.

See below, buddies! UVB cause nothing bad as long as you don't use too much and burn them their ass off.
The highest ever measured UVB radiation was measured in the Andes below an ozone hole, over 580μW / cm². It's probably too much but 300-400μW / cm² with 15 / 45min cycles should be safe.
Each and every outdoor plants gets some UVB. Let's take a mexican sativa grow near Mexico City, 2000m above zero, UV-Index is 12-14 in summer, that's ~300-350μW/cm²(factor 25) or 35mW/m² for 4-5h evey day. In Miami Florida they can get the same level. Even fiber hemp is not badly affected by UVB and there is no trichome layer filtering UVB on such strains.

The test are done with a UVB dose of 6,7 and 13,4kJ/m2, that's ~155 and ~310μW/s/cm² for 12h. That's a lot! My current reptile bulb is ~120-180μW/cm² at 1' distance and the only thing that was different than usual was more foxtailing and higher trichome density.

Test results Bluedream with and without UVB are done with Indagro Pontoon (2x 4ft bulbs per 4x 4', running for 15min/hour) and their latest LED fixture. Sorry, no link! But I've found them when I inquired about the UVB pontoons.

One of the old dutch guru's, I believe Jack Herer*), told in one of his books about fiber hemp that they brought fiber hemp to Jamaica. After a few generations trichomes began to form again and they adapt to the new enviroment. He assumed that at latitudes with low UV radiation each hemp species loses potency over time and the opposite happens when it gets more UV light. I still tend to believe that as the more I think of it the more sense does it make.

I had my 39w tube running about 50% of the time, say 6h per day, that's about 15kw / h in 9 weeks. I could have used 20w more white but my 440w fixture is anyway too strong for my small 2x 4' area. So in my situation it makes no sense to add more light but adding UVB does make sense. When you consistently pull good results and max yield per area the only thing left is to add some UVB to get a better product.

*)The Emperor's New Clothes or Why the Hemp Cultivation Should Be Legalized. At least that's the title when translated from my language

BTW, the test were done 1987, todays UVB bulbs like the PureUV from Agromax are much stronger. With 54w you got 440μW/cm² above a 2x 4' area(0,84m²) that would be 370μW/cm² above 1m2. For a dose of 13,4kJ/m²(higher dose in the test) you need ~310μW/s/cm² for ~12h. With 12h á 370μW/s/cm² the dose would be 16kJ/m².
 

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Dachem2010

Well-Known Member
Does anyone know the micromoles/s/w for the EB gen.2 trying to calculate my ppfd (rough estimate) it's not on their data sheet. Im trying to decide if me getting another HLG-185H-20A to run them around 1033ma is worth it.
 

nfhiggs

Well-Known Member
See below, buddies! UVB cause nothing bad as long as you don't use too much and burn them their ass off.
The highest ever measured UVB radiation was measured in the Andes below an ozone hole, over 580μW / cm². It's probably too much but 300-400μW / cm² with 15 / 45min cycles should be safe.
Each and every outdoor plants gets some UVB. Let's take a mexican sativa grow near Mexico City, 2000m above zero, UV-Index is 12-14 in summer, that's ~300-350μW/cm²(factor 25) or 35mW/m² for 4-5h evey day. In Miami Florida they can get the same level. Even fiber hemp is not badly affected by UVB and there is no trichome layer filtering UVB on such strains.

The test are done with a UVB dose of 6,7 and 13,4kJ/m2, that's ~155 and ~310μW/s/cm² for 12h. That's a lot! My current reptile bulb is ~120-180μW/cm² at 1' distance and the only thing that was different than usual was more foxtailing and higher trichome density.

Test results Bluedream with and without UVB are done with Indagro Pontoon (2x 4ft bulbs per 4x 4' 15min/hour) and their latest LED fixture. Sorry, no link! But I've found them when I inquired about the UVB pontoons.

One of the old dutch guru's, I believe Jack Herer*), told in one of his books about fiber hemp that they brought fiber hemp to Jamaica. After a few generations trichomes began to form again and they adapt to the new enviroment. He assumed that at latitudes with low UV radiation each hemp species loses potency over time and the opposite happens when it gets more UV light. I still tend to believe that as the more I think of it the more sense does it make.

I had my 39w tube running about 50% of the time, say 6h per day, that's about 15kw / h in 9 weeks. I could have used 20w more white but my 440w fixture is anyway too strong for my small 2x 4' area. So in my situation it makes no sense to add more light but adding UVB does make sense. When you consistently pull good results and max yield per area the only thing left is to add some UVB to get a better product.

*)The Emperor's New Clothes or Why the Hemp Cultivation Should Be Legalized. At least that's the title when translated from my language
Thanks for the links Random - I'll look at these when I have some time. Are these your test results?
 
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Randomblame

Well-Known Member
Does anyone know the micromoles/s/w for the EB gen.2 trying to calculate my ppfd (rough estimate) it's not on their data sheet. Im trying to decide if me getting another HLG-185H-20A to run them around 1033ma is worth it.
That's the numbers at nom. current for 3000°k strips...

@700mA(43,75mA per diode)
QER=4.84 µmol/J
LER=331.66 lm/W
= 2.55 µmol/J
@1050mA(65mA per diode) it's probably ~2,35μmol/J...
 

Randomblame

Well-Known Member
The two T12 UVB "pontoon" bulbs(40w each) only run 15min per hour and they mentioned a measured strength of 400μW/cm² 2' above a 4x 4' area, thats actually the same dose like 60 mins with ∅100μW/cm². Would be 4,32kJ/m²; a relatively low dose and comparable to the intensity my Arcadia reptile bulb puts out at 14"' distance. .
Nevertheless, there was already a difference of 14% with this relatively low dose and if you use more UVB the drug content increase almost lineary up to a certain point.
You only need a 2ft. Agromax(22$), a 24w electronic ballast(~9$), two screw in sockets(G5) for T5 bulbs(1$, ebay), some single core wire (2$) and a 100 x 550 x 1mm alu sheet for a reflector(5$). ~40$ and because of its strength a 2 ft. bulb should be enough for an 80 x 80cm or area(0,64m² or 6,85ft²).
I think that is not too much for a promising test. The total costs and the additional consumption of 15kwh each 9 weeks is minimal even at 25ct / kwh it's less than $4. After 1500h the output is still 80%, with 2500h 60% is left. If you use it 15min/h that's only 3h per day or 200h each 9,5 bloom weeks. One bulb should last at least 7 runs, 10 when you replace it when only 70% UVB is left. But with 70% it's still more UVB like a new reptile bulb produce.
 
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Dachem2010

Well-Known Member
Thank you randomblame so I'm coming in at 811 ppfd est. If I add another driver it will be 1495 ppfd I know it's a game of diminishing returns think it's worth it it will be a HLG-185H-20A so it can be dimmed
 

PSUAGRO.

Well-Known Member
I think kitehigh was averaging 5% thc bump consistently with his clones & lab testing using t5 uv_b(arcadia)......different strains, different results i guess? That's why you don't monocrop;)
 

Randomblame

Well-Known Member
I think kitehigh was averaging 5% thc bump consistently with his clones & lab testing using t5 uv_b(arcadia)......different strains, different results i guess? That's why you don't monocrop;)
Yeah, most probably strain depending too. Here the difference was only 2,6% between the two test buds but 4,32kJ/m² is a relatively low dose. But it's a linear increase, with a twice as high dose the result should be twice as good.@Aolelon (hollar at you, my friend) sended me 6 Agromax bulbs via USPS, because you can not buy them here with us. I'll replace my Arcadia bulb once it has run for ~1000h. I hope they'll do not burn my girl's ass off, lol!


Thank you randomblame so I'm coming in at 811 ppfd est. If I add another driver it will be 1495 ppfd I know it's a game of diminishing returns think it's worth it it will be a HLG-185H-20A so it can be dimmed
811μMol/s/m² sounds already very good and tops that grow closer to the light will anyway get higher intensity. If you shortened the distance lets say to only 8" you're certainly over 1000μMol/s/m².
You could do the first run with 811 and add a second fixture/driver one run later if you still think it's necessary. +1500 sounds perfect at first but in fact it will cause a lot more trouble and the difference in yield is probably only 20% or less for twice as much energy. Not because of the light just because of not enough area!
Also with the most productive strains (like BlueDream, PowerPlant, DutchDragon, ...) it's almost impossible to get more than 60g/sft and you have to have perfect environmental conditions to get to those regions at all.
I pull consistently "only" 45-50g per squarefeet in soil and in the hope of increasing it a little I'll be switching to a coco DWT system later this year. But my light will still remain the same apart of the UVB bulb. I could use up to 45w/sft if I want(I have 440w above ~9sft) but I always see light stress when I go higher than 80%(350w) and the end result remains more or less the same.
 

Dachem2010

Well-Known Member
That's kinda what I was thinking 2x the energy with 20% increase not worth it I'd rather work on increasing potency and widening the spectrum a lil with uvb, 400nm-430, 660-700nm to widen the spectrum to better fit the mccree curve and dam right now its 6 in from the small guys and 3 from the one that's gonna im surprise I'm not getting light stress on the auto they are sucking up nutrients like crayzie.
This is for the EB gen.2
eb gen2 spectrum.jpg
 

Piczkens

Member
Hi guys,
I want to build lamp with 1 ft EB Gen 2 strips.
6 strings in parallel, 3 strips in each string.
Can i use ELG-150-C2100A for this?
 

led1k

Well-Known Member
I did some calculations for a RIU poster in a micro box thread, maybe you saw it....
9x 280mm EBs at 1050ma will generate over 10,000 lumens, to saturate a 1.7sq foot area.
LESS than 100 bones to get the parts to achieve that. The light source consuming nearly ZERO vertical space. I'm actually considering several stackable boxes using the 2x2 formulas to maximize room volume....single plant mini rooms....
I like that idea. The concept of Blade Servers for growing bud! What's the latest on this?
 

led1k

Well-Known Member
my par meter arrived today, what is the best way to go about doing a par map i've never done one before? do i tape up some squares and just take measurements at like different heights? what heights you want me to test at guys? will test with single board (6 x strips at 300w total) under both boards, (600w total) and then will test under 4 boards at 1200w on the weekend.
I'm trying to figure out the spacing needed to get the most even PAR readings for my 15 2' EB Gen 2... Any hints based on your readings would be fantastic!
 
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