How many watts per SF?

wil2279

Well-Known Member
I'm looking at cob and qb fixtures... I'm going to do a 2x4 scrog. How many watts per SF would be optimum? I'm willing to spend whatever it takes to get the best, most optimum and efficient lights for my grow. I was looking at timber lights and hlg lights...
 

Airwalker16

Well-Known Member
30-50watts a square foot is what you're gonna get. You're gonna want to get a driver setup that will give you more power than you may need. This way, you have the ability to dim the lights and maintain control of your PPfd. This is done by choosing the "B" version of the Meanwell driver you're using. "B" is always the last character in a model #. You may actually find some strains can handle the more intense light and others may not. But regardless, having too much is always better than not enough to begin with here.

2X4 areas beg board builds. It's a rectangle.. if money is TRULY not a factor here, do yourself a favor and buy at least one if not all of the ChilLed Tech boards to either dominate or design a light around with. I'd use a Chilled board in the middle with strips using 2 along either lengthwise side of it and say 3-4/6-8 total 1ft(11") Samsung F-series Strips to fill in the ends oriented perpendicularly to the chilled board and strips.

| | | _______ | | |
| | | ====== | | |
| | | ====== | | |
| | | _______ | | |

___ strips
=== chilled board


Something like that? The top strip would be at the edge like the bottom one is though. The line just stays low when I type with that key. The strip rows you would want to space out more also. The blank spaces don't register in this posting program so I can't demonstrate it here.
 
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Retardid_greenthumb

Active Member
I'm looking at cob and qb fixtures... I'm going to do a 2x4 scrog. How many watts per SF would be optimum? I'm willing to spend whatever it takes to get the best, most optimum and efficient lights for my grow. I was looking at timber lights and hlg lights...
lux and par meters are king
 

wil2279

Well-Known Member
30-50watts a square foot is what you're gonna get. You're gonna want to get a driver setup that will give you more power than you may need. This way, you have the ability to dim the lights and maintain control of your PPfd. This is done by choosing the "B" version of the Meanwell driver you're using. "B" is always the last character in a model #. You may actually find some strains can handle the more intense light and others may not. But regardless, having too much is always better than not enough to begin with here.

2X4 areas beg board builds. It's a rectangle.. if money is TRULY not a factor here, do yourself a favor and buy at least one if not all of the ChilLed Tech boards to either dominate or design a light around with. I'd use a Chilled board in the middle with strips using 2 along either lengthwise side of it and say 3-4/6-8 total 1ft(11") Samsung F-series Strips to fill in the ends oriented perpendicularly to the chilled board and strips.

| | | _______ | | |
| | | ====== | | |
| | | ====== | | |
| | | _______ | | |

___ strips
=== chilled board


Something like that? The top strip would be at the edge like the bottom one is though. The line just stays low when I type with that key. The strip rows you would want to space out more also. The blank spaces don't register in this posting program so I can't demonstrate it here.
I want to keep this simple also. I am a carpenter... Not an electrician. Right now I was looking at 300 watt 3 board kits from timber grow lights... I also looked at the 3 board kits and lights from HLG. Then I looked at the 4 board light from timber that is 480 watts. Someone told me 480 watts was kinda overkill.
 

Humple

Well-Known Member
I want to keep this simple also. I am a carpenter... Not an electrician. Right now I was looking at 300 watt 3 board kits from timber grow lights... I also looked at the 3 board kits and lights from HLG. Then I looked at the 4 board light from timber that is 480 watts. Someone told me 480 watts was kinda overkill.
480 watts is absolutely overkill for a 2x4. Most people settle around 30-40 watts per square foot. Very rarely do I see someone exceed 40w - that's a hell of a lot of light, and you can definitely overdo it. Make sure you get something dimmable that will provide at least 30w sq/ft, and leave some headroom, just in case you need it.
 
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wil2279

Well-Known Member
480 watts is absolutely overkill for a 2x4. Most people settle around 30-40 watts per square foot. Very rarely do I see someone exceed 40w - that's a hell of a lot of light, and you can definitely overdo it. Make sure you get something dimmable that will provide at least 30w sq/ft, and leave somesome head, just in case you need it.
Thanks... I think I have found a 320 watt Samsung quantum board fixture that will be just about perfect for what I am trying to do... I can get a couple of them for around $800 which is also pretty acceptable. I was prepared to spend about twice that if I had to...
 

canadian1969

Well-Known Member
You're gonna want to get a driver setup that will give you more power than you may need. This way, you have the ability to dim the lights and maintain control of your PPfd. This is done by choosing the "B" version of the Meanwell driver you're using. "B" is always the last character in a model #
A and B functions are both dimmable, A by screwdriver (built in potentiometer), B by external potentiometer (100KOhm) that you have to purchase ($1 or less) and wire yourself. Just for clarification.

For QBs and Strips; 30 watts a square foot is fine, the height of the light also plays a factor, the closer you get your light to the canopy the less power is required. If you are only 12 inches above the canopy you may only need 15-20 watts per square foot. At 24" you would need 30-40.
 
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