mc130p
Well-Known Member
Same current, 2X the voltage = ~2x the power
I noticed a discrepency in data; Can anyone clarify?
tyb
COB efficiency Spreadsheets
- Thread starter nogod_
- Start date
UKpeanuts
Well-Known Member
Doer
Well-Known Member
More power? This says to me that the quantum loss may not just be from Current. Higher Voltage seems to waste electrons also.
If this is correct......
mc130p
Well-Known Member
Well, it's a double edged sword.....higher current means higher I^2R resistive heat losses.....
SupraSPL
Well-Known Member
Yep you guys got it. The first example is dissipating 23W and the second is dissipating 49W. So to make a direct comparison you have to use row 2 on the 36V chart which also dissipates 49W.
I should have included a 350mA row for the 72V version for a more clear comparison. That 23W row is extrapolated from the CXA graph. Cree did not expect them to be ran that low so they clipped that data off the CXB graph.
I should have included a 350mA row for the 72V version for a more clear comparison. That 23W row is extrapolated from the CXA graph. Cree did not expect them to be ran that low so they clipped that data off the CXB graph.
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SupraSPL
Well-Known Member
That is something I was surprised by too, you would think the high voltage version would have an advantage but according to the data sheet, not so.
medicinehuman
Well-Known Member
OK my 36v cbx3590's seem to be brighter @ 700mA than the 72v although they do have different drivers, HLG 185 700 AND INVENTRONICS 160w quad driver 700mA. I've been wondering for a few days about it. If anyone needs advice on roofing I might be able to help you 
Randomblame
Well-Known Member
There is definately something wrong deffinitiv. Exactly the opposite must be actually! Maybe the internal current poti have a defect. You can check the real power draw with a kill-a-watt.
medicinehuman
Well-Known Member
Yep something wrong , only 54.6 watts it's drawing. Lucky I have a few extra lights. I put a passive cooled @1050mA with a quad driver and it looks much better. Has anybody ever had to return a driver, how easy is it.
medicinehuman
Well-Known Member
DoctorDelta9
Well-Known Member
Awesome thread! Finally all the spreadsheets in one place.
I'm trying to calculate my par/ft2.
Trying to find the LER for cxb3590 72v 3000k CB.
I will be running
3000k x12
Over a 6x6 area
I'm trying to calculate my par/ft2.
Trying to find the LER for cxb3590 72v 3000k CB.
I will be running
3000k x12
Over a 6x6 area
alesh
Well-Known Member
Cree CXA/CXBs 80CRI 3000K is around 325lm/W.
Actionbone
Well-Known Member
Does enyone know the spreadsheets of cxb 3070/3590 5000k?
Doer
Well-Known Member
Fricking roofing! That is one those things that I can easily screw up. I mis-calculated the hip transition the one time I tired it. I had to pull up a bunch of material. Really, I may take you up on this. I am buying this house that has an addition....well. Maybe I can just send you a picture in PM later on this year.OK my 36v cbx3590's seem to be brighter @ 700mA than the 72v although they do have different drivers, HLG 185 700 AND INVENTRONICS 160w quad driver 700mA. I've been wondering for a few days about it. If anyone needs advice on roofing I might be able to help you
I have no doubt you could see the difference in the COBs. Oh well, I will make do with the counter-intuitive, yet again.
Doer
Well-Known Member
Smoking green since 1970. I just noticed that. I graduated high school that year, and had no green smoke ever, until college in the fall.
medicinehuman
Well-Known Member
You are an old fucker 
Doer
Well-Known Member
No you are an old fucker! Anyway, I did LSD a bunch of times before I smoked pot.You are an old fucker