Led design help

Rahz

Rahz

Well-Known Member
SamWE19 said:
Errm not sure what you mean.

I have around 1m of height between the top of the cobs and the apex of the roof. But from there it slopes down.

I believe I have enough room to build a 45degree reflector from the top of the Heat sinks. However I won’t be able to put the reflector to a horizontal plane as you say it would be 45 degrees in the opposite direction due to the slope of the roof which is already covered in diamond Milar

When I say 1.5m that’s 1.5m of pots.

So I have a plant holder every 30 cm and I have 5 stacked on top of each other which makes it 1.5 but the plants will be growing out of these at a 45 degree angle not completely horizontally.

So the top pot may be 150cm but the plant may end around 200cm
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Okay. Seems like you are planning a canopy wider that 4' anyway. I was just assuming your 80 sq/ft was two 4x10 zones. You have the basic idea though. 90 degrees minimizes the amount of light the needs to be reflected while still keeping the pattern tight. If you can squeeze 6' of vertical in there it would be ideal.
 
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SamWE19

Well-Known Member
Rahz said:
There's a guy here (don't remember who) that does that.
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With the way I’m growing I have 150cm footprint if you count the pot footprint, now because the plants grow upwards in reality the canopy layer would still technically be 150cm but from the bottom pot to the top of the canopy would be 200cm.

So when working out yield this would technically be 150cm footprint I reckon.

Although if enough light makes it down to the ground I may just throw in a coco pot on the ground and drippers. To up the yield

Just realised my drawing is missing a pot tho. I’ve only drawn 4 on top of each other it should be 5
 
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SamWE19

Well-Known Member
Now with your recommended reflectors it would look like this rahz.

I could also put a coco pot with drippers on the floor to increase the footprint and catch that usable light?

That would increase the overall canopy to around 180cm I think that’s the max I can get it too

Do you think enough light would reach that far down from the cobs?
 

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Rahz

Rahz

Well-Known Member
SamWE19 said:
Do you think enough light would reach that far down from the cobs?
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By my thinking if a lamp is hung at 16" above canopy the 'wall' should be 16" from the side of the lamps light emitting surface. According to your drawing, and if you think the bottom row of plants won't reach 16" below the bottom cobs then yes, that's good usable area and coir pots would work fine.

Can you add more pots to the bottom of the shelves? Maybe something not to do right away but if taking care of 2 systems get to be a PITA it might be worth doing.
 
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SamWE19

Well-Known Member
Rahz said:
By my thinking if a lamp is hung at 16" above canopy the 'wall' should be 16" from the side of the lamps light emitting surface. According to your drawing, and if you think the bottom row of plants won't reach 16" below the bottom cobs then yes, that's good usable area and coir pots would work fine.

Can you add more pots to the bottom of the shelves? Maybe something not to do right away but if taking care of 2 systems get to be a PITA it might be worth doing.
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Can’t really add more hydro pots to the bottom of this system as the box on the bottom is the reservoir. I could add another pot if I move the system closer. As you see in the drawing the top pot is nearly touching the sloped roof. For every 20cm or so I bring it forward i can probably add another pot.

If I bring it forward another 20cm or so the plants will most likely finish at around 30cm from the cobs. Depending on what the par readings are I may be able to do that. But would I have 6ft of canopy that close to the cobs?
 
Moflow

Moflow

Well-Known Member
Here are some lux to par conversion numbers.

Cree COB 3000K 80 CRI 69.1
Cree COB 3500K 80 CRI 70.2
Citizen COB 3000K 80 CRI 69.4
Citizen COB 3000K 90 CRI 62.2
Samsung 561C 3000K 80 CRI 68.9
Divide Lux by above numbers.

For example, 50,000 lux ÷ 69 .1 = 723 , if you're using Cree 3000k at 80cri.
 
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SamWE19

Well-Known Member
Moflow said:
Here are some lux to par conversion numbers.

Cree COB 3000K 80 CRI 69.1
Cree COB 3500K 80 CRI 70.2
Citizen COB 3000K 80 CRI 69.4
Citizen COB 3000K 90 CRI 62.2
Samsung 561C 3000K 80 CRI 68.9
Divide Lux by above numbers.

For example, 50,000 lux ÷ 69 .1 = 723 , if you're using Cree 3000k at 80cri.
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I’m using citizen 3000k 80 CRIS and a mixture of 90 CRIS. But if I use the 62.2 for arguments sake that would mean I only have 980 par 30cm from 60w of 50% efficient cobs. Can’t be right. Unless my lux meter is junk.

I’ll know for sure In a few weeks when the par meter arrives
 
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SamWE19

Well-Known Member
In regards to my nute dilemma I think I’m gonna just go with ionic grow and bloom with nitrozyme, ionic boost, liquid silicon, and some agricultural aminos works out like 180 usd a grow instead of 500-700 for other lines. Don’t see how expensive nutes are any better probably just marketing gimmicks
 
Rahz

Rahz

Well-Known Member
SamWE19 said:
If I bring it forward another 20cm or so the plants will most likely finish at around 30cm from the cobs. Depending on what the par readings are I may be able to do that. But would I have 6ft of canopy that close to the cobs?
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6ft was based on 40cm to canopy. If you move to 30cm it changes to a 64" canopy or 5ft 4 inches. This would take 8 inches out of play, 4 off the top and 4 off the bottom. If you can also raise the lamp 4 inches you will be rid of the bottom 8 inches.
 
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SamWE19

Well-Known Member
Rahz said:
6ft was based on 40cm to canopy. If you move to 30cm it changes to a 64" canopy or 5ft 4 inches. This would take 8 inches out of play, 4 off the top and 4 off the bottom. If you can also raise the lamp 4 inches you will be rid of the bottom 8 inches.
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Because of the sloped roof I have no room for an extra pot so can’t really increase the canopy size so I might just bring the canopy to 30cm if the ppfd numbers allow. I should have the meter by Tuesday. The postage seems to have gone a lot quicker than expected
 
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SamWE19

Well-Known Member
Well I have played around with the meter today and I am very impressed.

I have not got any reflective material currently on any side of the cobs. It’s not optimised at all but even without all of that the numbers are insane.

Goes to show lux meters are absolutely useless to determine what the ppfd is.

I havnt done an accurate mapping atm as I have soil pots in the room atm whilst I was sorting out the hydro system but when the soil harvest is done with I’ll do an accurate mapping but some quick readings where as follows:

1300 ppfd in the middle at 30cm
800ppfd edge at 30cm
600 ppfd 90cm Away on the edge
900ppfd 90cm away in the middle
1200 ppfd 40cm Away in middle
Average 800-1200ppfd from canopy to 90cm away from lights.

So even on the very edges of the grow I have 800ppfd at 30cm and then 600ppfd 90cm away. Barely any drop over such a big distance.

So I can have 2ft tall plants with 800-1300ppfd across the entire canopy and also the sub canopy.

This doesn’t include installing reflective sheeting around the edges of the grow so these numbers will also improve.

Glad I bought this meter so I know for sure

I will probably just let the plants finish at 40cm since I know they will get solid buds all the way down and won’t need lolypopping
 
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