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LED grow light, how many lumens?

P

pwb

Hi, i'm new to growing plants, but i love chili so i think i will give it a try. I use 2x180watt LED light. Its 60 Bridgelux High power 3W LED on each lamp. Its full 10band made for growing plants. I see that one 3watt bridgelux give 180-220 lumen, but since its grow light (red, blue and some ir) is that different lumen? I now have the light maybe 50-60cm over the plants, i moved them closer that on the picture, but is that to close? Could the plants get sunburn? Could this realy give 24.000 lumen?
https://dl.dropboxusercontent.com/u/87802055/2014-04-14%2021.53.31.jpg

 
 
leds usually don't run them at full voltage so they don't do the max lumens. Why? because running at lower voltage (like half) produces less heat / waste, thus making the light more efficient and longer living.
 
IR have 0 lumens because lumens are the measure of visible light(and we can't see ir... atleast i can't lol). Also you can't really measure red / blue leds with lumens because they produce only a part of the visible spectrum. 
 
Anyways, you can move them to like 15-25cm for a day and see if they get burnt(they won't).
 
Lumens only indicate how "bright" a light source is to the human eye.
This is not relevant to plants.
 
 
OKGrowin said:
leds usually don't run them at full voltage so they don't do the max lumens. Why? because running at lower voltage (like half) produces less heat / waste, thus making the light more efficient and longer living.
 
IR have 0 lumens because lumens are the measure of visible light(and we can't see ir... atleast i can't lol). Also you can't really measure red / blue leds with lumens because they produce only a part of the visible spectrum. 
 
Anyways, you can move them to like 15-25cm for a day and see if they get burnt(they won't).
Click to expand...
 
If you run an LED at a lower voltage it wont light. They have a forward voltage you have to meet. Once that is met the brightness is controlled by the current. Voltage is nothing but on or off.
 
Some IR wavelengths bleed into the 'visible' spectrum. There's no defining line.
 
LED's can and do "burn" plants by bleaching the chlorophyll.
 
pwb said:
Hi, i'm new to growing plants, but i love chili so i think i will give it a try. I use 2x180watt LED light. Its 60 Bridgelux High power 3W LED on each lamp. Its full 10band made for growing plants. I see that one 3watt bridgelux give 180-220 lumen, but since its grow light (red, blue and some ir) is that different lumen? I now have the light maybe 50-60cm over the plants, i moved them closer that on the picture, but is that to close? Could the plants get sunburn? Could this realy give 24.000 lumen?
https://dl.dropboxusercontent.com/u/87802055/2014-04-14%2021.53.31.jpg

 
Click to expand...
 
I seriously doubt that light is 24000 lumens. You can probably go to 30cm off the top of the plants.
 
Yes red and blue are measured differently. Their brightness has to be converted to equivalent lumens.
 
If it has been HPS, how much watt do i then need to have to grow? And how close could a 400watt HPS have been to the plant if it didnt had the heat?
 
If it had been HPS with a lot more light than the LED then the plant will die off until it reaches equilibrium with the new light.
 
As far as how close you could get a 400w HPS without the heat this is just a guess, but I would say within a few inches. And the difference is that HPS bulbs do not focus the light like a 60 or 90 degree lens you will find on a lot of LEDs.
 
When I put my LED within 6-8" of a plant the leaves bleach and start dying. My LEDs all have 90 degree lenses I think.
 
There is a point where there is just too much light for a plant regardless of whether or not there is heat associated with it.
 
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