tyler.durden
Well-Known Member
I have 3 systems touching each other, they're about 40in x 25in. I figured putting a 420w rectangular LED board above each system would give me 1260w of LED. Do you think that would work to replace the 2 1000w HPS?
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- Thread starter StinkBud
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ttystikk
Well-Known Member
Well that's spot on the ratio I suggested; 2000/1260=.63 or 630W vs 1000W of HPS.
Given the other parameters I mentioned in terms of temperature and RH I think it should work pretty well.
When you mentioned this at first, I was under the impression you were running three 1000W HPS fixtures and that's why I said what I did.
Tracker
Well-Known Member
Once you get over about 45w of LED output power per sqft of canopy, the returns on more power are diminishing unless you supplement co2. Have you measured/mapped ppfd on your canopy? Do you know what numbers you're hitting now?
tyler.durden
Well-Known Member
I don't know the numbers, I just know that I have 2 1000w Hortilux HPS in air cooled hoods over a canopy of approximately 8ftx4ft. I have lower ceilings now than before, so I can't raise them as much as I'd like, so some plants top colas get a little heat stressed. I think LED would suit my setup better, so I'm trying to study a lot before I invest.
ttystikk
Well-Known Member
(420W x 3 = 1260W) / (8' x 4' = 32ft²) =
39.375W/ft² which isn't crazy but it's going to be plenty for LED.
I think you'll really enjoy the results.
Tracker
Well-Known Member
39w per sqft of canopy is good to work with. Bar style LED's will spread the light intensity over the canopy so much better. There's still higher intensity in the center relative to the edges, but the light is spread out so much better.