Help With Strip Spacing for 800 ppfd

butterbudface

Well-Known Member
I recently did a grow with 49 samsung strips, powered by 7 x 320w meanwell drivers. The area was 45 square foot or 4.2sqm.

This seemed like way to much light, i could be wrong here as i did not do any ppfd calculations.

For my next run i want to make sure i have my strips spaced just perfect.

Can any of you clever led gurus please help with ppfd calculations?

This round will have 10 x 240w drivers and 50 strips. What must i space them at to get 800 ppfd?

What info do you need to help me calculate this if anyone is willing to help.

Is 800ppfd the correct amount of light to aim for?
 

canadian1969

Well-Known Member
map it out with a cheap ebay Lux meter, that will work fine to give you a rough idea of the PPFD (with conversion) search Lux to PPFD calculation, but the Lux readings alone will tell you where you are uneven in coverage/intensity.
 

butterbudface

Well-Known Member
map it out with a cheap ebay Lux meter, that will work fine to give you a rough idea of the PPFD (with conversion) search Lux to PPFD calculation, but the Lux readings alone will tell you where you are uneven in coverage/intensity.
I want to start welding the light frames and need to work out the spacing before i start building the room
 

tomate

Well-Known Member
I want to start welding the light frames and need to work out the spacing before i start building the room
Then we need more information to help you.
1. the exact dimensions of your grow space (metric)
2. which strips exactly
3. which drivers exactly

To get an even light distribution, you just have to space the strips evenly. The resulting average ppfd depends on how much light you have in total over a given area.
 

shimbob

Well-Known Member
I recently did a grow with 49 samsung strips, powered by 7 x 320w meanwell drivers. The area was 45 square foot or 4.2sqm.

This round will have 10 x 240w drivers and 50 strips. What must i space them at to get 800 ppfd?
If the first round, with a total of 2240watts was too much light, the next round at 2400watts is going to be even worst, regardless of strip spacing and assuming the same space.
 

nfhiggs

Well-Known Member
I recently did a grow with 49 samsung strips, powered by 7 x 320w meanwell drivers. The area was 45 square foot or 4.2sqm.

This seemed like way to much light, i could be wrong here as i did not do any ppfd calculations.

For my next run i want to make sure i have my strips spaced just perfect.

Can any of you clever led gurus please help with ppfd calculations?

This round will have 10 x 240w drivers and 50 strips. What must i space them at to get 800 ppfd?

What info do you need to help me calculate this if anyone is willing to help.

Is 800ppfd the correct amount of light to aim for?
Run the strips ( 50 strips at 2400 watts) through the Samsung calculator to get the total lumens, Divide the lumens by the par conversion factor for the CCT in this chart:

Samsung conversion chart.png

That will get you the total PPF. Divide that number by the square meter area they cover to get the average PPFD
 

canadian1969

Well-Known Member
I want to start welding the light frames and need to work out the spacing before i start building the room
okay so build one drivers worth, one panel, what 5 strips per driver? lay the strips in the frame loose so you can adjust them and then do what I said with the Lux meter, but yeah the guys are right, if you are building on this level buy a proper quantum meter man. Sound like you may not be doing this for yourself, so doubly, get the proper tools. Seems like a question your previous build would have answered anyway. You seriously built a 45sq' grow space and never put a meter under any of it?

p.s. Welding? how are you building your frames?
 

butterbudface

Well-Known Member
Run the strips ( 50 strips at 2400 watts) through the Samsung calculator to get the total lumens, Divide the lumens by the par conversion factor for the CCT in this chart:

View attachment 4159578

That will get you the total PPF. Divide that number by the square meter area they cover to get the average PPFD
This will help me.

Then we need more information to help you.
1. the exact dimensions of your grow space (metric)
2. which strips exactly
3. which drivers exactly

To get an even light distribution, you just have to space the strips evenly. The resulting average ppfd depends on how much light you have in total over a given area.
I am trying to determine the grow space. the strips are 4ft long, i need to find the spacing that will determine my growspace.

there is a data sheet for exactly the strip and driver that was used? not sure what more you want?

If the first round, with a total of 2240watts was too much light, the next round at 2400watts is going to be even worst, regardless of strip spacing and assuming the same space.
not the same space dude, this is a new room, i am keeping the old one as is. I understand that if you put more watts over the same space it will be more light.

All that cash on lights and you can't buy a cheap quantum meter...
I like to see the calculations on paper man.

okay so build one drivers worth, one panel, what 5 strips per driver? lay the strips in the frame loose so you can adjust them and then do what I said with the Lux meter, but yeah the guys are right, if you are building on this level buy a proper quantum meter man. Sound like you may not be doing this for yourself, so doubly, get the proper tools. Seems like a question your previous build would have answered anyway. You seriously built a 45sq' grow space and never put a meter under any of it?

p.s. Welding? how are you building your frames?
It goes something like this

fixture.PNG
room.PNG

Yeah pretty much scaled it up from my cob setups, same amount of watts but they run way more efficient that why i want to try stretch the light out as much as possible if that makes sense.

I'm going to do as @nfhiggs said and try the samsung calculator.

Might post here for some more help.
 

nfhiggs

Well-Known Member
I am trying to determine the grow space. the strips are 4ft long, i need to find the spacing that will determine my growspace
OK, this is easy - Start with the Samsung calculator and enter the strips your using and the number (50) and run the current until the wattage reaches 2400. Then take the total lumens and divide by the conversion factor to get the total PPF. Divide that number by your target PPFD (800) and you'll have the area in square meters they will cover.
 

butterbudface

Well-Known Member
OK, this is easy - Start with the Samsung calculator and enter the strips your using and the number (50) and run the current until the wattage reaches 2400. Then take the total lumens and divide by the conversion factor to get the total PPF. Divide that number by your target PPFD (800) and you'll have the area in square meters they will cover.
I have been trying all morning, i am struggling with the samsung calc
 
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