LED grow lights - how much is enough?

cannabis mechanic said:

To be clear, what I have is an LED assembly that draws 200W of power. It is advertised as a 2000W light, and I was under the assumption that this means it produces the equivalent LIGHT OUTPUT of a 2000W incandescent lamp. I am getting two more of these soon, so my total "advertised" wattage will be 6 kilowatts. Of course my grow lights will not be dissapating 6 kilowatts of power. I thought that was assumed.

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Best to avoid anything advertised by scammers.
You can't get more out than you put in.

HLG + QBs (and the clones) are good if you want LED and the power they advertise, is the power you get.

CM, confusion reigns supreme when it comes to classifying light fixtures.
While we all care about how many watts of power we pull from the outlet, the plants only care about how many photons of light(PAR) they receive.
Somebody posted a nice list of the ppfd levels it takes to grow.
This is where confusion enters.
Different light sources have a wide range of efficacy at converting watts to photons.
The most accurate method to see how 'much' you need is knowing how efficient your fixture is.

GBAUTO said:

Different light sources have a wide range of efficacy at converting watts to photons.
The most accurate method to see how 'much' you need is knowing how efficient your fixture is.

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Nonsense,
It's never going to exceed 100%
With the Amazon burples probably 50% of power from the socket.

I'm sorry for confusing you.
I don't see where you're getting this 100% or 50% value.

What I was trying to convey is that it's the number of photons available in the grow space.
Watts are the misleading part of the description.
You need to know how efficient the fixture is at producing those photons if you want to use watts as a metric.

what's your ballast say?

A ppfd chart shows how well a fixture spreads the light over a space. PAR and other values are important but do not tell the entire story. It is very easy for lights to have high PAR values and also have a poor distribution in a ppfd chart.

cannabis mechanic said:

Sodium lamps are not an option for me. As I mentioned in an earlier post, I am a ham radio operator. HPS lamps put out lots of spurious RF, and would fuck up my HF communications. That's a big reason why I chose low-voltage LEDs.

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If you can wire a plug mate you can build a great light very easily these days.

Its like lego. Don't even have to solder anything.

However even a DIY fixture will cost you more than a cheap light on amazon. But it will certainly out perform it too by a lot and last you many years longer than a cheap LED.
Typically a cheap LED has a low efficacy , is built from old tech, run hot so lifespan is less, made with little quality control and probably zero customer service.

The most common reasons for using LED are to get more light for the power your using or to get less heat for the same light output.
I think your the first guy ive seen with your reason.

If anyone's been salty with you its only because its a question asked daily. Not your fault though, its hard to get real info on the internet when every other guy on youtube is making a living trying to peddle crap at you and every "best LED light 2020" webpage is just an amazon traffic generating BS page designed to part you from your hard earned cash.

If you did want pointing in the right direction for DIY LEDs then just hola, loads of folks on here will help out!

coreywebster said:

Typically a cheap LED has a low efficacy , is built from old tech, run hot so lifespan is less, made with little quality control and probably zero customer service.

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This is the biggest benefit of using top-tier diodes vs old epistar diodes.
We are approaching almost double the light output at the same power level, so it's a HUGE difference.

GBAUTO said:

This is the biggest benefit of using top-tier diodes vs old epistar diodes.
We are approaching almost double the light output at the same power level, so it's a HUGE difference.

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Yeah this is what a lot of folks don't get, they assume all LEDs have good efficiency , which they do in comparison to incandescent but nobody grows with incandescent and HPS is pretty reasonable lm/w . Lots of LEDs are a good chunk worse, not that long since they were boasting about 110lm/w

coreywebster said:

Yeah this is what a lot of folks don't get, they assume all LEDs have good efficiency , which they do in comparison to incandescent but nobody grows with incandescent and HPS is pretty reasonable lm/w . Lots of LEDs are a good chunk worse, not that long since they were boasting about 110lm/w

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Its also critical to understand spread of a fixture and its purpose. I know you guys know this better than me, but its the other critical piece that few look into.

Ali express is your best friend always custom build your light for your grow area. It's far cheaper and you can fix em way easier. And you can get more power more cost effectively.

I am currently using 6 - 1000watt.Mars Hydro and grow 12 Autoflowers to about 2ft to 4ft and produce a Quarter Pound per plant at least every 70 days.
I'm also doing full cycles under the same lights and get 4ft plant with about 8 ounces per plant or more. These are only 40 days in and have 30 days of flowering left. Budget LEDs are a whole lot better now. People will scoff at it. Especially old heads. But if I can get full spectrum output on the same levels and pull less watts from the wall then I'm going with that. Efficiency of light spectrum is what you are after. Not just what it draws from the wall. It has to convert that energy into usable light. So just because someone has a 600watt hps doesn't mean that it's better than a 1000watt led. Studies show leds convert more light more efficiently.
Try a plant under led and one under traditional lighting and see what you think for yourself.

Id recommend grasscity or thcfarmer forums cannabis mechanic.. you can find decent info here.. but its such a toxic place that you will spend 2x as long digging through insults and condescension before you get the info you ask for ...
This forum from my brief experience tends to be just full of internet gangsters or lonely hippies who really have 0 communication in real life.. so they have noone to verbally abuse and are soft soo definately noone to physically abuse.. so they rant and rave on a pot forum and talk down to anyone with questions.. belittle them.. call them names.. because theyve been inadequate their whole life.. and growing pot is their 1 thing in life they can do without totally fucking up.. and they want to get self worth out of it by bashing others and feeling on top..
Rather than teaching others soo they can get better themselves..
Truth is.. why would they really want you as good as them.. then theyd lose their last spot in life they were better than others and able to look down..

Anyways.. just go to thcfarmer .. half decent.. and truthfullt grasscity seems very friendly.. cause idk about you.. but id rather receive shit info kindly and from a nice person.. than good info from a dickhead who talks shit to me and makes me wish we were face to face soo i could bash their head in..

Goodluck buddy.. and as far as the initial question..
Your lights will be fine for your plants.. my plants are rather large rn.. but i tend to aim for about 100w draw per plant but im sure id be fine with far less .. if your true draws 200w a light.. 3 lights.. 600w.. you should be good.. best ones to answer it will undoubtedly be your plants though.. if they seem happy .. who cares about anything else..
I suppose the truth is.. until we can talk to a plant we will never really know what they really need or how a light makes em feel haha
Goodluck bud

There are no mysteries when it comes to lighting.

Go outside see what people can do with sunlight and see the obvious standard to which we look to create indoor lighting.

There is the technology, the efficiency, the spread, power and its application. Many technologies exist for different setups.

How a thread can elicit so much emotion is interesting to me. We were discussing lighting, not politics, lol.

Every person in this thread wanted to help direct towards better lighting. Some people arent stoned when they post and are cranky. Others have smoked all day and get bitchy. Lol you arent a newbie if you havent been razzed and reacted with an F U feeling at least once. I did, lol. Go look it up if it makes you feel more like part od the group.

I know many of the posters who posted in this thread, not personally, but their knowledge levels. They all can and will take your interest in lighting to a higher level.

When friends marvel at how THIS newbie could grow stuff better than anything they have had from a store or other growers, the reason is my lighting. It creates dense, potent stinky buds.

We are sensitive creatures. Lighting however shouldnt really create so much emotion....lets just grow some killer sxxx instead and share how we do it.

Efficiency and spread is what almost every non commercial indoor grower is concerned with. We can pinpoint efficiency for any fixture and discuss it objectively. That does require that you be willing to accept you may have made poor or mediocre choices in the past. Its worth it imo.

I spent 6 months researching everything before buying a light. That is extreme, but i got it right the first time. Im happy to try and help anybody.