Weezze
Well-Known Member
Ok! But if you compare a LED light and HPS that give the same lumens, I'm pretty sure the LED would be better to grow! 
Advice about wattage of LED light
Ian Bastage
Well-Known Member
When you are talking about LEDs, a watts for watts comparison is very misleading. Everybody tries to use the power consumption but consumption ratings are just that — they do not tell you how much light is getting to the grow area. And the marketing guys love to use big numbers in their model #s to sound impressive but typically they mean nothing.
LEDs grow lights are in their 4th (?) generation or so. Bare LEDs with a reflective housing, LEDs with a focusing lens in front, LEDs arrays with a focusing housing and now COBs which are LED arrays on the same small circuit board. Different generations use different wattage chips that they drive at different percentages of total possible output. 3W, 5W, 50W etc. So, more confusion. Of course, each successive generation does the job more efficiently then its predecessors but they are all still available in the marketplace today competing for your $s.
So, how do you compare? Look for PAR charts that show you the light intensity spread at a stated distance - usually 18" or 24" above the surface. As long as the PAR chart shows you the spacing of the measurements, it can tell you if the light will cover your entire grow area with figures above 400 μmol. That is probably the best layman's guide to the effectiveness of an LED light imho. And this is assuming that it covers the color spectrum that the plants need, which is another topic altogether.
LEDs grow lights are in their 4th (?) generation or so. Bare LEDs with a reflective housing, LEDs with a focusing lens in front, LEDs arrays with a focusing housing and now COBs which are LED arrays on the same small circuit board. Different generations use different wattage chips that they drive at different percentages of total possible output. 3W, 5W, 50W etc. So, more confusion. Of course, each successive generation does the job more efficiently then its predecessors but they are all still available in the marketplace today competing for your $s.
So, how do you compare? Look for PAR charts that show you the light intensity spread at a stated distance - usually 18" or 24" above the surface. As long as the PAR chart shows you the spacing of the measurements, it can tell you if the light will cover your entire grow area with figures above 400 μmol. That is probably the best layman's guide to the effectiveness of an LED light imho. And this is assuming that it covers the color spectrum that the plants need, which is another topic altogether.
There'd be a lot less confusion about LEDs if people would simply STOP buying any LED grow light panel that is manufactured and/or sold by an entity that misrepresents its products' wattage! Then those companies would go out of business.
It's like when people first started growing with CFLs, and no few of those people thought that their 23-watt CFL was as capable as a 100-watt one, since the things were advertised as being so.
If a company wants to sell me a "600w" LED panel, it better show that it's consuming ~600 watts when plugged into my Kill A Watt meter. I don't care what the sum total of the "theoretical maximum" of all the little LEDs are - try to run that much through them and they'll melt, catch on fire, produce smoke as their final accomplishment, or just quietly fail.
Lumen (singlular and plural) don't grow plants, lol. Lumen are for reading the newspaper by. It's a measurement that is heavily weighted in preference to the portions of the spectrum that the human eye perceives as being the brightest. It's a totally nonsensical scale to measure a GROW light's ability with.
It's like when people first started growing with CFLs, and no few of those people thought that their 23-watt CFL was as capable as a 100-watt one, since the things were advertised as being so.
If a company wants to sell me a "600w" LED panel, it better show that it's consuming ~600 watts when plugged into my Kill A Watt meter. I don't care what the sum total of the "theoretical maximum" of all the little LEDs are - try to run that much through them and they'll melt, catch on fire, produce smoke as their final accomplishment, or just quietly fail.
Ok! But if you compare a LED light and HPS that give the same lumens, I'm pretty sure the LED would be better to grow!
Lumen (singlular and plural) don't grow plants, lol. Lumen are for reading the newspaper by. It's a measurement that is heavily weighted in preference to the portions of the spectrum that the human eye perceives as being the brightest. It's a totally nonsensical scale to measure a GROW light's ability with.
Mayne
Well-Known Member
still, lumens represents Brightness on any scale. We can say the same for PAR meters being bullshit to, agree?
it "Meesures" blues and reds, but because the intensity from those blues and reds are brighter, you get a higher reading. BUT, it doesnt meesure how much cyan, or 660nm or 430nm, if the light has it or not. and those specs are important as reds and blues.
Lumens, lux, numbers gives people baseline information that cant afford $1,300 equipment.
Yes, The companys are out to sell, sell, sell. They dont care about a handfull of people making their own lights, because there are 20 others that arnt informed, rushing, no research, and they will make their money off them, like all businesses do, right full so, ..
Personally, i think wattage is overrated myself, right now anyways. Ill know more when this run is in completion.
its about light intensity and penetration of undercanopy illumination saturation.
it "Meesures" blues and reds, but because the intensity from those blues and reds are brighter, you get a higher reading. BUT, it doesnt meesure how much cyan, or 660nm or 430nm, if the light has it or not. and those specs are important as reds and blues.
Lumens, lux, numbers gives people baseline information that cant afford $1,300 equipment.
Yes, The companys are out to sell, sell, sell. They dont care about a handfull of people making their own lights, because there are 20 others that arnt informed, rushing, no research, and they will make their money off them, like all businesses do, right full so, ..
Personally, i think wattage is overrated myself, right now anyways. Ill know more when this run is in completion.
its about light intensity and penetration of undercanopy illumination saturation.
EastCoastGhost
Well-Known Member
I have Mars 1200 (585 actual draw) in a 4×4 and I got great results, almost 23oz of really sticky dence bud in my first grow so hopefully I will get even more this next run...️
Sure, since brightness is a subjective term that has to do with our perception of the amount of light that we're seeing. Ergo, of course a light source that has a higher lumen specification appears to be brighter.
Measuring a light's prowess at growing cannabis by referencing its lumen specification wasn't exactly a great idea when everyone and their brother were all using the same basic output high-pressure sodium lamps. Trying to compare two light sources that have different spectral outputs by comparing their lumen specification is... foolish.
Ian Bastage
Well-Known Member
The trouble is that that 600w fixture might do a piss poor job of reflecting the light to your grow surface, so it still might be a bad purchase.
One big advantage of LEDs that is little mentioned is that fact that they don't degrade with usage. Yes, they will eventually fail but the light they produce until it fails is consistent. The light output of traditional incandescent, fluorescent & HID lights all gradually degrade over time so the output after 2000 hrs is not the same as a new lamp.
I've read that high temperature causes decreased performance, but IDK if that's true or not. And, even if it is, IDK if that would be a permanent thing, or go away after the components return to their designed operating temperatures.
Yes. Every now and then you have to drive to the store, get a new bulb, come home, unscrew the old one, and screw the new one in. At which point the used bulb can serve as an emergency backup for the rare time when one actually fails. Or it can be given to your poorer buddy, who'd he much happier to run your year-old bulb than his three-year old bulb (or to replace the one that he got clumsy and broke, et cetera).
IDK what the actual failure rate on LED grow panel components is. Just from reading sponsors' product threads, it's clear that they do fail from time to time. The percentage is probably low, at least for the first year or three. I've got one in use that's been running ~18 hours for a year or more with no failures <KNOCKS ON WOOD> .
But I wonder, if/when I see an issue, how long that'll put the thing out of service while I either order replacement parts, wait for them to arrive, and install them. Or, if I do not feel up to performing the repair myself, how long it'll take to ship my big, 35-pound LED panel off (and how much it'd cost to do so :icon_roll ), get repaired, and get shipped back. I'm guessing the answer is "longer than it takes to drive to/from the store for an HID bulb."
If I have a bulb failure, I grab a backup. Sure, its performance is degraded. But it's a 45-second walk to the (storage) closet and back, lol. At which point, I can go get a new bulb at my leisure.
How many people who use LED grow panels have spares? Quite a few - but not all. If you're just starting, read the reviews/tests to find out what this week's latest and greatest is... You probably only bought the one, both because you're just getting into growing and because the really good LED products aren't cheap. A lot of people are handy with a soldering iron and can see well enough for fine-detail work. They'll have their light back up quicker (assuming the parts arrive in a timely manner). Some very few people will have had the forethought to order a few things ahead of time, in case of a future failure. But not many.
There are both positives and negatives. In a perfect world, I'd like to have three more LED panels just like the one I'm using now (or a newer generation of the same basic product, since there have effectively been TWO wattage and technology upgrades just in the less than two years that I've been playing with it). But that'd be a rather significant hit to the budget, even if I was quite well off (which I am not). Right now I'm just growing in a dinky little 3'x3' space. I mostly switch between that, a 3'x5.5' space, and a 4'x4' tent, depending on a number of factors. So small potatoes and low budget. And I don't grow to sell - which is just a thing, as far as that goes, but[.b] it means that I cannot look at spending a significant amount of money as a business investment, lol. If this LED panel suffered some kind of catastrophic failure... I'd replace it with a HID setup and both a HPS and MH bulb. It'd be a substantially cheaper for the same general neighborhood in terms of performance.
If I WAS growing lots more, and selling product... I'd still have to set down and calculate the difference in yearly costs (wouldn't be a huge amount) versus the difference in the cost of the hardware. And then, seeing how the technology is still improving (due to being relatively young - when considered solely for growing plants), the break-even point would have to be - at most - within two years. Otherwise, I'd still go with HID. Give it ten - or even three, who knows? - years and my opinion may change. That's just how I feel today.
Ian Bastage
Well-Known Member
You are right TS. As a new amateur, I have a new light but if it failed I would have to scramble for replacement parts and jury rig a short term solution while I waited. You are lucky to have a backup plan.
I considered a DIY COB or a manufactured COB (which usually look like homemade COBs anyway) but I decided that a good mid grade LED <$400 was fine for now. When pot prohibition ends here (presumably next year), I may add a COB or two to really flame the grow surface. But first, I have to learn to grow.
I considered a DIY COB or a manufactured COB (which usually look like homemade COBs anyway) but I decided that a good mid grade LED <$400 was fine for now. When pot prohibition ends here (presumably next year), I may add a COB or two to really flame the grow surface. But first, I have to learn to grow.
LedTestLab
New Member
600 W LED light for 169 us? Its impossible guys, just impossible! Good quality driver costs for 600w LED's already is 150 us . Then best material also for LED cooling is aluminium and as we know aluminium is not the cheapest material... So in my opinion 600W LED for 169 us is nothing more like chines bullshit.. At the moment Best COB's at market is Citizen Clu series...read abouth them, Japanes really make the best in led industry right now
This is not entirely true....
All LEDs will lose output over time, definitely not as drastic of a loss as a HPS bulb... but they do lose output over time...
A lot of the rate at which this occurs is due to the thermal management and junction temperature the LED's operate at....
This typically is called Lumen Maintenance and generally you will see a measurement such as LM80 at 50,000 hours, which means that at 50,000 hours of operation, the LED will be only outputting 80% of its light or in other words operating at 20% less than when new.
Generally most premium chips like cree SMD's will last anywhere at LM80 from around 40,000 to 68,000 hours but again this depends on the junction temperature, thermal management and also what mA they are driven at.
Most cheap Epistar, Epiled and generic LEDs generally will have a LM80 of less than 35,000 hours even though most manufactures still claim 50,000 hours of use...
Some chips like OSRAM SSLs have a lumen maintenance of LM95 at 100,000 hours which means that at 100,000 hours, they have only lost 5% of the light output and still push 95% of the light output... again, all dependent on junction temp, how hard they are driven, thermal management.
So even though you are right that they don't lose output as fast as HPS, which could lose 20% of its light within the first 5000 hours, they still do lose output over time.
Now most LED manufactures do not have 50,000 hours to test LEDS before market, so Lumen Maintenance figures generally are based off calculations of a LED being run for 5,000 hours, measured at even increments and then the curve is calculated as a perceived failpoint.
Mayne
Well-Known Member
Love your shows Ice,
Ian Bastage
Well-Known Member
I stand corrected. Thanks for the detailed answer.
Thanks guys...
I definitely like to shine a light on the subject.....lmao
JohnnyC
Well-Known Member
My 900w meizhi along with supplementary light for flowering works like a charm with great results. I’ve had it for 2 years now and it hasn’t let me down. The truth is it does put off a decent amount of heat on full spectrum. (With both veg and bloom switches on). I have very good ventilation also and efficient air exchange With tower fans. The meizhi 900w led works extremely well in veg (with bloom switch off) and in fact it is the only led I use for veg.
This light seems to work best for my setup with veg light for veg, then a week and a half after the flip to 12/12 I use only the bloom switch because it puts off shit for heat so I can get pretty close after the flowering stretch. This is when I introduce another supplemental led light that brings my growing environment to a max temp of 75-77 degrees light on and 69 lights off with rh from 42-48
This light seems to work best for my setup with veg light for veg, then a week and a half after the flip to 12/12 I use only the bloom switch because it puts off shit for heat so I can get pretty close after the flowering stretch. This is when I introduce another supplemental led light that brings my growing environment to a max temp of 75-77 degrees light on and 69 lights off with rh from 42-48
I'm guessing that it produces roughly the amount of heat that a 400-watt HID would, since (if I'm not mistaken) that's a 418-watt device. Probably about 1,426.216 BTU of heat per hour.
JohnnyC
Well-Known Member
I would say you are right on the money
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Northlight®
Active Member
It's not that hot.
In my setup at the moment i have the Meizhi 900 (400w from the wall) + one 400w HPS.
The heat emitted is almost the same
In my setup at the moment i have the Meizhi 900 (400w from the wall) + one 400w HPS.
The heat emitted is almost the same
JohnnyC
Well-Known Member
Not to hot but I don’t like running at 81-82
JohnnyC
Well-Known Member
I’m talking about my environment and conditions what works for me at the moment. Sounds like you have shit figured out And dialed in nicely northlight
