CCCmints
Well-Known Member
NO. LED:HPS = 750:1000
Anyone who tells you otherwise, is either misinformed, or spreading misinformation.
Your yield on a HLG550?
- Thread starter kdt15
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Anyone who tells you otherwise, is either misinformed, or spreading misinformation.
OneHitDone
Well-Known Member
Ok let's do some simple real world 123's
We'll even us the number those in this section like to use for a Gavita DE output - 1800 ppf
So you have 8 x 1800 = 14400 ppf
1440 / 1450 (HLG 600H) = 9.93
So in reality it is 10 HLG 600's to replace your 8 DE's or 13 HLG550's
CobKits
Well-Known Member
actually a hard and fast rule that 750W of LED is equivalent to 1000W of HPS is misinformation in and of itself because that would imply that all LEDs are the same efficiency and all HPSs are the same efficiency
you could be compating a 1.3 umol/ J blurple vs a 1.7 umol DE HPS or you could be comparing a 2.3 umol/J HLG with a 1.3 umol/J SE HPS
so a fundamental understanding of the units of measure of efficiency is important
no its not real that 400W of low-end blurples can replace a 1000W DE
yes its very real that 550W of a 2.3 umol/J HLG can replace a 1000W SE
see onehit's example above, his gross PPF comparison is even more straightforward
Perfect response exactly what I was thinking
CCCmints
Well-Known Member
What leads you to the conclusion that 550w LED @ 2.3 umol/J is a sufficient replacement for 1000W SE? I agree blanket statements are not useful, but if people need a generalization, 750:1000 is far more accurate than 400-500:1000. I also strongly disagree with your statement that PPFD is a useless measurement. The biggest reason HLG-550 can't compete with 1K SE HPS is because it has the same uniformity flaws with half the power.
The HLG-550 produces 30% less PPFD over a 4'x4' reflective space than 1K SE HPS. This was observed through physically testing a 1K SE HPS setup with the highest quality equipment I could think of, and with the data HLG provides on their website. So, if the HLG-550 runs @ 507.30w, and produces 30% less PPFD, what 550w LED design do you claim succeeds 1000w SE HPS??
I've assembled and tested a 757w COB array. The uniformity flaws are ironed out, and it produced nearly 9% higher PPFD than the 1K SE HPS.
So, 507.30w (HLG-550) produces 625 PPFD @ 22" in a 4'x4' reflective space. 1000w (SE HPS) produces 892.79 PPFD @ 22" in a 4'x4' reflective space. 757w COB array produces 970.41 @ 22" in a 4'x4' reflective space.
PPFD is the measurement that matters. It doesn't matter how efficient a fixture is if it can't evenly distribute its light across the desired footprint.
[PPFD/W]
507w HLG-550 = 1.23
757w COB array = 1.28
1000w HPS setup = 0.89
It'd be nice if you could replace 1K SE HPS with 50% less power, but you simply cannot, yet. I've seen no concrete evidence supporting this claim. I wonder where people even get this figure from...Cause after actually doing the tests, it seems blatantly obvious you can't succeed 1K SE HPS with 50% less power.
CobKits
Well-Known Member
the fact that 550W @ 2.3 umol/J = 1265 umol and 1000W at 1.3 umol/J = 1300 umol
you cant claim any kind of accuracy when you disregard efficiency entirely
its not useless in general, just for quantifying total output of a fixture. its analogous to measuring your engine's horsepower via the speedometer, literally impossible
input power is irrelevant. coverage pattern is irrelevant (provided its not insanely wasteful in getting it to canopy, which its not). photon output is 100% of it
again its arbitrary as you are not directly measuring all of the light as you would with a sphere or goniophotometer. its a simplification. look at bugbee's flat plane vs sphere discussion for an example of why it is a simplification and requires correction. your measurement attempts are flawed in the exact same way that crees "reference design" test does
http://www.cree.com/led-components/media/documents/HorticultureReferenceDesign.pdf
...except in the opposite manner. Cree suggests 550W of intermediate-efficiency LED tech can replace a 1000W DE, BUT they are comparing a par map of highly focused light over a 4x4 with no stray light from teh LED, vs a gavita which is casting a fair amount outside which is disregarded.
In the same way the gavita reflector focuses slightly tighter than a QB rig throwing (at least a little) light all the way out to almost 180 degrees. in your setup throeing light like that doesnt achieve your desired intensity, but in a warehouse with overlapping light patterns it sure does... if falls outside of the prescribed area of the fixture but is additive to the areas outside of it illuminated by other fixtures. Basically when you say your PPFD ratios are off from PPF ratios, you are demonstrating a missing measurement of light not shining on your space (site specific not a fault of the light) You dont mention your measurement technique. cree used 10000 points in a 4x4 which is extreme but i would think a grid of 3-6" would be sufficient (4 to 9 points per square foot)
correct and nobody is claiming that. youd need 2.6 umol/J at system level to do that were not there yet. i mean its doable but right now is prohibitively expensive, >$2000 to replace a 1000W SE. you'd need to buy 2 of the HLG550s and dim them down to 250W each, youd be right about there using the common rule of thumb of cutting current in half increases efficiacy by ~10%
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wietefras
Well-Known Member
@CCCmints Others have measured bigger differences between led and HPS.
One obvious cause for the discrepancy with your measurements is that it makes no sense to put a COB fixture at 22". Indeed that will lose you a huge amount of light. The fact that well distributed COB fixtures can be much closer to the plants means you cut down on wall losses tremendously. If you needlessly add those losses back in the yes, you will end up with warped results.
HPS 1000W should be at 30" to 36" height, Quantum boards at 18" and COBs could be as low as 8" depending on how many COBs you are using. Those are the actual heights you'd be operating them at and not some arbitrary value of 22"
Each extra inch in height will cost you somewhere between 1% and 2% of the light. So yes, at 18" quantum boards will also lose a lot of light on the walls like HPS does, but the COBs shouldn't. So you could cause your measurements to be as much as 20% too low on the average COB PPFD.
Led strips can go even closer. With 550W of led strips running at about 2.5umol/s and at most 4" to 6" above the canopy, you could beat a 1000W HPS SE
Also, you mention wattages. Are these actual draw? Because for HPS you simply assume 1000W and in every test I have seen, they do actually receive more than 1000W. That's even before driver losses. You coul;d easily be 10% off there too.
One obvious cause for the discrepancy with your measurements is that it makes no sense to put a COB fixture at 22". Indeed that will lose you a huge amount of light. The fact that well distributed COB fixtures can be much closer to the plants means you cut down on wall losses tremendously. If you needlessly add those losses back in the yes, you will end up with warped results.
HPS 1000W should be at 30" to 36" height, Quantum boards at 18" and COBs could be as low as 8" depending on how many COBs you are using. Those are the actual heights you'd be operating them at and not some arbitrary value of 22"
Each extra inch in height will cost you somewhere between 1% and 2% of the light. So yes, at 18" quantum boards will also lose a lot of light on the walls like HPS does, but the COBs shouldn't. So you could cause your measurements to be as much as 20% too low on the average COB PPFD.
Led strips can go even closer. With 550W of led strips running at about 2.5umol/s and at most 4" to 6" above the canopy, you could beat a 1000W HPS SE
Also, you mention wattages. Are these actual draw? Because for HPS you simply assume 1000W and in every test I have seen, they do actually receive more than 1000W. That's even before driver losses. You coul;d easily be 10% off there too.
CobKits
Well-Known Member
depends on the optics
cobs without reflectors have similar radiance patterns to discrete diodes. it all comes down to number of emitters and spacing between them. if you wallpapered the roof of a tent with any of the following:
-cobs (like 25 cobs per square foot)
-boards (continuous with no space between)
-strips (at small equal intervals say no more than an inch or two apart)
the radiance patterns would be literally identical.
of course with less emitters you need more height to get uniform coverage
a one cob fixture would be closer to an HID and would need 24-36+ inches to evenly illuminate
ANC
Well-Known Member
There are nice calculators you can use.
I took my 1.2 x 0.6m trays and divided them into three... as I am using 3 100W strips.
They have an output of 115 degrees. which means the lights need to sit at about 15cm to cover the whole 3rd with no waste.
PPFD levels are also nice in the sweet spot at this level. Even with colas starting to raise up in flowering, the lower canopy is still well lit.
I took my 1.2 x 0.6m trays and divided them into three... as I am using 3 100W strips.
They have an output of 115 degrees. which means the lights need to sit at about 15cm to cover the whole 3rd with no waste.
PPFD levels are also nice in the sweet spot at this level. Even with colas starting to raise up in flowering, the lower canopy is still well lit.
since1991
Well-Known Member
Welp....Iam keeping my 8 Gavitas for now anywAys. Iam not spending 4 to 10 k on lamps anytime soon thats for damn sure. Lol. You guys speak in ways I just cant understand. Nor do I want to. Makes my head hurt. If that's what it takes to get into the led world or buy a frikin grow light without getting ripped...the led thing has some growing up to do. I want no part of it. Got screwed about 8 years ago on some ridiculous led claims I fell for too. About 2k worth of JUNK. Iam not doing it again. Still salty after all these years from that fiasco. Felt like I bought a lemon from a used car salesman. I pull about 25 to 28 ounces of perfectly dried and cured top flower per Gavita 6/750. On the 600 watt setting only. Consistently too. The cross lighting and the way I got them hanging (Gavita helped me with that) is the key for me. And its something I could of never of got with even 10 singles ended 600 watt hps fixtures. 200 ounces bare minimum every 60 to 70 days from 4800 watts. And Iam very happy witj that. But if I can squeeze the same yield from even 3000 - 3500 watts of real power..the savings in electric bill would be really nice. But again...I hear such conflicting claims and answers from growers smarter than me with all the technical/sciency jargon. I cant be spending 6 or 10 thousand frikin dollars on lights again. Not anytime soon. My girl would probably leave my ass. Lol. My weed sells its obvious but not anywhere like it did back in 2000 or 2001. Big bucks for a gamble on led lamps (again!!!) just isnt happening. Iam definitely giving the led thing more time.
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Evil-Mobo
Well-Known Member
Nothing wrong with the lamps you have. If I had the headroom and the rooms electric would handle it that's what I'd be running. I'm only running LED now because I have to in the current situation. If not my 600's would be up and I'd be trying to figure a way of getting DE lamps setup in my larger space. It takes time to weed through all the BS because you have a lot of claims thrown out and around be people who don't have any experience with the subject, or who are pushing their own agenda to sell product. Good luck with your growing sounds like you're doing just fine as is.
Getgrowingson
Well-Known Member
2 units has been my best so far but mine is the diy 600w version . Running low yielders like cookies and og crosses etc
NanoGadget
Well-Known Member
OneHitDone
Well-Known Member
The wattage thing is interesting, you never hear anyone comparing the HLG550 to the Gavita 6/750 Flex fixture with the SR Reflector. Sure narrows that wattage gap doesn't it??
There is definitely still a place for SE lamps. It's called Air-Coolability. Anyone in a box or tent will become very fond of it.
Don't hear of many running cobs at 8" unless your talking about seriously under-driving them, like 20W??
since1991, pucker up brother! better get Rocket Mortgage on the phone for a second to purchase some HLG's
At least Spectrum King is honest enough to say that the reality on the led's is 5 years and then plan on making the investment again
since1991
Well-Known Member
Naw. Iam cool with the Gavitas for a skosh. Iam done spending money on equipment fer awhile. My rooms are dialed and my basement is a bud assembly line. Thx for the heads up. Alot of bowshit to sift through on these forums. And it can get truly wallet draining if you let it. Oh..btw. My cousin has my old setup I hooked her up with when I bought the Gavitas a few years back. 7x7x7 tent with 4x600 watt single endeds..air cooled. And she kills it in yields. 70 to 80 zips every 60 to 70 days( over 4 pounds always and sometimes 5). Hell of a setup and still.running strong after all these years. Definitely a place for se hps. For sure. People say these are yesterdays news...I beg to differ.
View attachment 4115133
The wattage thing is interesting, you never hear anyone comparing the HLG550 to the Gavita 6/750 Flex fixture with the SR Reflector. Sure narrows that wattage gap doesn't it??
There is definitely still a place for SE lamps. It's called Air-Coolability. Anyone in a box or tent will become very fond of it.
Don't hear of many running cobs at 8" unless your talking about seriously under-driving them, like 20W??
since1991, pucker up brother! better get Rocket Mortgage on the phone for a second to purchase some HLG's
At least Spectrum King is honest enough to say that the reality on the led's is 5 years and then plan on making the investment again
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CCCmints
Well-Known Member
But you are claiming that. Solely considering the total photon output when determining which fixture performs better is flawed practice. Its no better than saying LED:HPS = 750:1000; Both statements ignore very important variables.
You can't claim any kind of accuracy when you disregard how well a fixture's light spreads over its advertised footprint. This is really the most important figure to observe. Its not like my fixture sacrifices efficiency to achieve a higher PPFD. And it beats 1K SE HPS even with its highest PAR spike being 249µmoles/m2/s less than HPS’. I’m still going to send my fixture out to be tested in a sphere, and the report they produce will be valuable. However, I’m more concerned with PPFD and uniformity rather than obsessing over efficiency. That doesn’t mean I run my chips @ 100w each…But you see my point.
But what makes PPF a more valuable measurement than PPFD? I wouldn't call either one "useless". Both must be considered to determine the efficacy of a lighting system.
Strongly disagree. Simply focusing on the total photon output, and ignoring canopy coverage, is a bit ludicrous. How could input power and coverage ever not be considered important factors?
What makes measuring the actual output of your fixture in a real environment inferior to measuring it in a perfect sphere? I get that a sphere measurement is not useless, and I plan to send my fixture to the same lab HLG used to have it tested in one, but I care about PPFD/uniform light distribution way more than micro improvements in efficiency. Both figures are valuable.
49-point test with 2" squares about 5" apart.
CCCmints
Well-Known Member
I’ve measured them both at different mounting distances of-course, but I wanted to showcase the fact that LED can conquer 1K SE HPS with 25% less power draw and no mounting distance handicap. I agree with you, definitely can put the fixture closer than 22”. I’m not sure about 8”, but definitely closer than 22. Why do you say COBs can be placed so much lower than Quantum Boards?
I know it draws a bit more than 1000, but I don’t agree with the difference being 10%.
I’m interested in why you say COBs can be placed so much closer.
wietefras
Well-Known Member
Why not measure it then?
The distance is determined by the desired uniformity of lighting. You want the darkest area's to still have about 80% of the average light intensity.
With 120 degree angle COBs I measured and ran simulations and it turned out that at 2/3 of the distance between COB and canopy you get this uniformity. Barring some small regions in the corners. Or run it up to the height same as the the full distance to have some more play for growing plants. Going higher than that and you are just wasting light on the walls.
A regular COB fixture is designed to have one COB per sqft. This means a 12" distance from COb to COB and therefore an ideal height between 8" (2/3 * 12") and 12". With led strips you can set the height go to half the strip distance.
For HPS lights, you essentially have one big light. Which in a 5'x5' tent means you if you take 2/3 of 5', you end up at 40". In general you'd use 36", so pretty close.
A QB is basically a big single light source. With QB's in a 5'x5' you use 4 boards, but they are very close to each other. So it's a bit of a guess if the rule of thumb actually applies. I've seen PPFD matrices of a single QB in a 2x2 and indeed the ideal height turned out to be 18" which is also the height recommended by HLG). Which again, is pretty close to the 16" the rule of thumb would give you.
So for 4 QB's in a 5' tent, I would actually revise my estimate. For 4 QB's in a 4x4 tent it would be 18", but 4 in a 5x5 I'd say 5' *2/3 = 20" would be the rule of thumb. Perhaps even 22" because you need a bit of extra height since the QB's are mostly in the center and not distributed evenly over the grow.
In essence it boils down to how much area each light needs to cover. This determines how high it needs to be above the surface to produce that spread. If you have more distinct points of light, the height needed will get smaller.