DIY COB LED Calculator

mx5spd

Well-Known Member
Newest Version gets me Java Exception error. I miss the good old days. Started making lights with KNNA years ago. grab a handful of Osram Dragons glue them to the biggest chunk of AL you could find and Presto "We have Nugs" LOL. Now its a bunch of engineering I need to build a new light LOL


Will my machine restarted twice dings several times and now it works. I neither question fate or the computer Gods.
 
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mr. Amsterdam

Well-Known Member
Sorry I don't have a solution. Seems to be some single cases and it seems to happen to users outside US. It's beyond my knowledge. Someone posted earlier that they had to change their settings and language on their OS. I'm not sure how that gets connected. Try running it on your phone...

I thought you were wondering what number to put in the Tj field. For the most part, people around here use 50, as in 50*C.
Yes i did fill in 50 or 55 oC but it wasn't working, so i thought that i have Tj wrong but it isnt't working in general because we don't come from the US. Where do i need to make adjustments on my computer in my settings so i can make it work?
 

bggrass

Well-Known Member
Yes i did fill in 50 or 55 oC but it wasn't working, so i thought that i have Tj wrong but it isnt't working in general because we don't come from the US. Where do i need to make adjustments on my computer in my settings so i can make it work?
I don't know. I did not set up a restriction in it. Maybe @joe666 can pitch in and tell you what he did...
 

mx5spd

Well-Known Member
Gentlemen, Thank you for such a labor saver. In an hour or so I had worked four or five arrays compared costs and came to conclusions. Maybe some of you more experienced guys could give these numbers a quick look.

1.56 sq ft continuous grow popsickle cabinet

(2) CLU 1818 @ 1.05 amps
Total Watts per Sqft 68.59
Par Watts per Sqft 29.49
PPFD 1542.55
10x14 USA Heatsink profile passive

Think that's enough light?
 

joe666

Member
I don't know. I did not set up a restriction in it. Maybe @joe666 can pitch in and tell you what he did...
first thing i did was set everything to usa english everywhere keyboard and all localisation settings , but i since then returned to my native keyboard and citicalc still works , it seems to be related to the region and format settings i put in under format english united states ( that place where you set the date formats etc like M/d/year or D/M/year etc i am in windows 10 64bit , i am not 100% sure if it works because of this only or if having other keyboards input layouts available in the list helps , but setting all to usa english works here if all else fails . you can revert to your other settings once done with calc.
bgggrass any chance it has to do with the date format month/day/year / day/month/year ? thanks for the tools by the way :)
 

bggrass

Well-Known Member
The PPFD based on canopy area, What distance is that referring to anyone know?
I was asking the same question when I made the calc.... I was told that distance doesn't matter.... If you figure it out, I'll add the modification.
 

joe666

Member
The PPFD based on canopy area, What distance is that referring to anyone know?
well distance of light source would make the canopy area variable and since its fixed in the calc , distance does not matter light has no where else to go.
having said that , adding a light source distance tab in calc with a variable canopy area would be nice if possible though , would add the possibility of finding out the most area you can use with x amount of cobs :p
 

MeGaKiLlErMaN

Well-Known Member
The PPFD based on canopy area, What distance is that referring to anyone know?
1ft.

well distance of light source would make the canopy area variable and since its fixed in the calc , distance does not matter light has no where else to go.
having said that , adding a light source distance tab in calc with a variable canopy area would be nice if possible though , would add the possibility of finding out the most area you can use with x amount of cobs :p
Distance does matter with PPFD. At one ft you get 1542ppfd, once you back off a bit it drops. The calc always assumes this length as a set standard.
 

MildGro

Member
I'd love to give this a shot - is there a problem with the link?

Edit - sorry was looking in the wrong place duh
 
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bggrass

Well-Known Member
Sorry if this has been asked already

Will this be updated for Vero 29 gen 7's or are the V2's too similar in efficiency to need a change?
What are the numbers for gen 7? I've been out of the loop but if someone has the numbers, I'll look into it when I have time
 
Here's SupraSPL's spreadsheet that I modified a bit using the values from the Gen 7 data sheet.
Some of the factoring values have been changed to get the lumen #'s somewhat close to the data sheet #'s.

Someone should check my math because I am a complete noob at this stuff, just trying to learn.

Comparing the fV of the data sheet and Supra's spreadsheet seems a little off.
42.4V @4200mA on the Gen 7 Data sheet vs 42V @3600mA on Supra's spreadsheet (assuming he used 29V2 values?)

https://www.dropbox.com/s/ef7lyfaxlidtzji/Vero 29 Gen7 Spreadsheet.xlsx?dl=1
 
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