Randomblame
Well-Known Member
@wietefras
I have LER and QER for LM561c from HLG's website. QER was calculated for 380-780nm I think.
$1200 dollar budget for 8'x4', strips or Cobs?
- Thread starter Shua1991
- Start date
@wietefras
I have LER and QER for LM561c from HLG's website. QER was calculated for 380-780nm I think.
projectinfo
Well-Known Member
Ya I'm not saying it can't be done, I use strips and really like my setup is all haha
The entire light is cool to the touch and I can touch the plants with the strips
http://rollitup.org/t/flower-pics-blueberry-canuk-seeds-feminized.958471/#post-14059463
wietefras
Well-Known Member
That 321 doesn't sound right. The QER is indeed for the full range and that's not the one to use for PPF calculations.
I compared all the 80CRI SPDs to see which was more efficient in PPF or YPF:
YPF corrects for the McCree curve. It also uses a wider range (360-760nm) To me that seems like a fairer comparison still than PPF. It's funny how it's pretty much the reverse of ordering by lumen.
Last edited:
Rahz
Well-Known Member
Nice. I'm finishing up a 3500/80 vs 3000/70 grow. It will be close but I'm thinking the 3000K 70CRI lamp will take the blue ribbon for yield. It already won the veg portion of the grow. The 3000K sample dominated under a par meter vs 3500/80, 3000/90/80, 2700/80 with and without Mcree factored in.
Rahz
Well-Known Member
I asked earlier and didn't get the answer I was looking for, so I will rephrase. What do you expect final plant height to be in that setup? I have an interest in stacking grows so would be helpful to know what kind of final plant height you're dealing with.Ya I'm not saying it can't be done, I use strips and really like my setup is all haha
The entire light is cool to the touch and I can touch the plants with the strips
View attachment 4087926
http://rollitup.org/t/flower-pics-blueberry-canuk-seeds-feminized.958471/#post-14059463
wietefras
Well-Known Member
Yes I was surprised that for the LM561C 80CRI 3000K beats the 2700K and 3500K in PPF/W. Not so much the 2700K, but the Cree 3500K is normally higher in PPF than 3000K. Which is why people mostly use Cree 3500K instead of 3000K. Guess for these Samsung strips 3000K is the best option? Or perhaps 2700K if you can find it.
That's all based on datasheet figures though.
Rahz
Well-Known Member
Yea. I've noticed estimates aren't lining up with results under a meter. A previous grow indicated the 90 CRI samples beating out the others despite not having the best par on paper or under a meter. After this test, assuming the 70 CRI sample is the winner, I'll do 3000K 70 -vs- 3000K 90 and revisit that situation.
projectinfo
Well-Known Member
Final height for me will probably be 2 feet above the pot.
And I've got like 4 ft to spare for height
6 plants per 2x4 table so I flowered at 13 inches approx
I'm sure you would figure out the draining and height. And I'm using an indica so it's a low plant.
I don't like the idea of stacking personally because it seems harder to maintain. But to each their own
I built a table frame over my res, then put a flood table in the frame.
Connected all the drains to drain into one bucket.
And I top feed pure coco, every day.
If your going to stack maybe N. F. T. , or top feed, constant feed water running over your roots
Randomblame
Well-Known Member
Hmmm, the LER/QER difference might be because they calculated LER and QER at 65mA, maybe a different datasheet?
Yeah, it looks funny but at the end it's logical. Good that I ordered mine in 3000°K. Only knew the calculations for CRI70, 80 and 90 from @Rahz thread but I assumed that these are transferable to strips as well and 3000°K/CRI80 provides the best performance.
You confirmed my assumption, thanks!
Last edited:
Randomblame
Well-Known Member
nfhiggs
Well-Known Member
24 strips will hit 655W running at nominal test current - that covers one 4x4 tent. If you want to run them at 50% of test current, you need 48 per tent. 100 total just gets you the bulk price discount from Digikey.
wietefras
Well-Known Member
They seem to use a rather different SPD than is in the datasheet. Perhaps they got something from the sphere test they had done.
Also did the SPD for the 70CRI and 90CRI 3000K leds, but they came out even poorer. Which is odd, because the 70CRI is available in S7 bin and gets up to 178lm/W, but then the LER is much higher (345lm/W) so PPF and YPF come out lower than with the 80CRI 3000K. Which goes against Rahz's findings that the 70CRI performed better.
You're welcome
Serva
Well-Known Member
you don't need 655w... 16 sqft x 30 w/sqft = 480w
that's why 70 strip are enough at half current for 4x8
nfhiggs
Well-Known Member
You said in your original post "500-600 watts". So I was working towards 600W. I rounded upwards in my figures since its good to have extra headroom to work with. You can always dim down, but you can't dim up.
Rahz
Well-Known Member
Results within 2%. The 3000K 70CRI lamp produced slightly more but also needs to be cured a bit more than the 3500K 80CRI. Once that's done the finals will be one way or the other by about 0-1% so it's a tie.
Keep in mind, the 3000K 70CRI is kicking out a little more than 3% the PAR of the 3500K 80CRI lamp. This is a reasonable indicator higher CRI (red shift to higher nm peak) produces better spectrums for flowering growth. Unfortunately a phosphor penalty still exists so it ends up breaking even, at least in this particular test.
I built my DIY LED fixture using Solstrips. They seem to be the best value out there for quality LEDs as far as I know. They use the same chips as Quantum boards - Samsung LM561C. Strips run $19.99 ea and the cost for pre-wired drivers is also fair. He also does some "sheet" configurations if you want to go that way.
https://solstrip.com/en/solstrips/25-210-solstrip-x1-400.html#/45-cct-3500k
You can run the strips at up to 50 watts ea all day long with cheap aluminum channel as a heat sink or buy sinks from them. Lower power levels are more efficient as with any LED. I have been very impressed with the customer service and quality of the strips. My plants love them.
https://solstrip.com/en/solstrips/25-210-solstrip-x1-400.html#/45-cct-3500k
You can run the strips at up to 50 watts ea all day long with cheap aluminum channel as a heat sink or buy sinks from them. Lower power levels are more efficient as with any LED. I have been very impressed with the customer service and quality of the strips. My plants love them.
OLD MOTHER SATIVA
Well-Known Member
the more i use no lens/reflector cobs the more i am impressed
..packs it on
and you can get real close
..packs it on
and you can get real close
Randomblame
Well-Known Member
You can get them a lot cheaper direct from the manufacturer. At least he says that the 3500°K strips only have LM561b+. The shop owner should take CRI90 into the offer, because so far there are no strips in higher CRI classes.
And as we know plants love them.
7,50$
https://m.alibaba.com/product/60730934376/Quantum-boards-96-LED-Samsung-lm561C.html?spm=a2706.8288997.0.0.75021fd79UMjhO
That would work for folks who need 50 strips at a time! Not real practical for small growers though. Plus there are all the usual risks for buying from alibaba - like getting ripped off and trying to handle warranty claims or dealing with scams and fake led's etc etc.
Id much rather pay a little more, and buy only what I need, from a reputable dealer, in-country, that I can trust not to screw me over or rip me off.
Actually, buying from that guy would have cost me more than 3 times as much as buying from Solstrips. Of course, I would have had 44 left over strips... if I ever got the order. Maybe I could also go into business selling LED's!
Not
