COB efficiency Spreadsheets

BOBBY_G said:

i wish there existed a micro-trowel, you know, with the 'castle' shaped edge of a given size like you use to apply thin set for tile work

http://floorelf.com/using-the-proper-trowel

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try a small flea comb maybe ?

How much heat are y'all picking up at the diodes as opposed to the drivers?

I know it depends on how hard your driving the unit... I want to be using 3590's driven at about 25 watts each. What component should I expect to put out more heat? Diode or driver?

drivers are 90% efficient
chips are 40-60% efficient...

same power running thru each

EfficientWatt said:

Great Idea

Here is cxB3590 CB bin :

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Is there anywhere an explanation of all the different terms/columns above that i could read?
thanks

First column is the drive current.
Fourth column is lumens @ 50°C
Fifth column is voltage @ 50°C
Sixth column is dissipation wattage @50°C
Seventh column is fourth column divided by Sixth column
8th column is the seventh column divided by the LER (LER is the maximum theoretical lumens per watt in this case 325)
Ignore the last column because prices are always changing

yosim said:

Is there anywhere an explanation of all the different terms/columns above that i could read?
thanks

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nogod_ said:

First column is the drive current.
Fourth column is lumens @ 50°C
Fifth column is voltage @ 50°C
Sixth column is dissipation wattage @50°C
Seventh column is fourth column divided by Sixth column
8th column is the seventh column divided by the LER (LER is the maximum theoretical lumens per watt in this case 325)
Ignore the last column because prices are always changing

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excellent, thanks mate

ttystikk said:

I'd like a thermal paste on rye, with the hot bologna...

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'On toast'

I was looking at some citizens COBs. So does this mean the CXB3590 is still the most efficient at the moment? I know these are 3000k, but would be similar for 3500k right?

in a given chip size, 3500 will always be brighter than 3000K

youre also looking at 4 different models of citizens there

watt for watt in a given color temp and CRI, the 1212s are about 10-15% less bright than the crees, 1812s are a little less bright, 1818s are a little more bright, and 1825s are about 10-15% brighter

Nevermind wow. Never seen 64% efficiency COBs yet. What driver to drive 4 of these bad boys? What does that last column stand for? $/PARW? Wouldn't less $ per Par Watt be better? That part never made sense to me.

kaivorth said:

What does that last column stand for? $/PARW? Wouldn't less $ per Par Watt be better? That part never made sense to me.

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That entire chart is the same chip at different currents. the softer you run it, the more efficient it is, but also has lower unit output for the same chip cost, so $/PAR W goes up

CobKits said:

That entire chart is the same chip at different currents. the softer you run it, the more efficient it is, but also has lower unit output for the same chip cost, so $/PAR W goes up

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Oh man I'm an idiot. The dollars coming from chip cost vs light output. I was thinking more efficient, why would $ per PAR go up? Makes perfect sense now. Thanks for clearing that up.

Recommendations for drivers for these? I plan to run 4 of them at 700ma I think. Enough for a 2'x4' closet?

so there still is no real basis for the low current measurements on those chips

in the chart above going from 1.4A to 0.7A: CXB efficiency increases from 56.34 to 64.01 (+13.6% relatively), which may be a little optimistic.

in supra's tests (https://www.rollitup.org/t/cxb3590-1500w.878136/page-35#post-12156936)
PPFD/W goes from 7.75 to 8.5 (+9.7% relatively)

in a few of my tests ive done:
DB bin:
9.53>10.56 +10.8%
8.81>9.80 +11.2%
8.80>9.70 +10.2%
CB bin:
8.19>8.99 + 9.8%

seems like 10-11% bump is more real world as compared to +13.6%. the 1% variation between sSupra's tests and mine could very well be methodology (his tests were more 'pulsed', mine are steady state which would bias low current data ever so slightly higher)- its still well into the 60s in any case

kaivorth said:

Oh man I'm an idiot. The dollars coming from chip cost vs light output. I was thinking more efficient, why would $ per PAR go up? Makes perfect sense now. Thanks for clearing that up.

Recommendations for drivers for these? I plan to run 4 of them at 700ma I think. Enough for a 2'x4' closet?

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I run 12 in a 2x4 tent in my closet, but not needed I am sure
Not sure there is a 700ma driver that likes 4 though

I think I would run 6 or more in a 2x4 in at 700ma

kaivorth said:

Oh man I'm an idiot. The dollars coming from chip cost vs light output. I was thinking more efficient, why would $ per PAR go up? Makes perfect sense now. Thanks for clearing that up.

Recommendations for drivers for these? I plan to run 4 of them at 700ma I think. Enough for a 2'x4' closet?

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there are all kinds of meanwell HLG-xxxH-C700B drivers, depends on your system size. each chip uses ~33.4V at that current

http://www.meanwell.com/product/led/LED.html

in any case despite its reputation its difficult to recommend the CXB for low current operation due to its cost as all chips perform great at that wattage. heres 5 chips performing within +/- 3% of the CXB at 23W. the chip below it is a $12 chip.

My, my, what a difference a year makes.

ttystikk said:

My, my, what a difference a year makes.

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My lights were joining the "Flintstone Era" before I even got done with them haha

Holy crap you're right!!! $12 wow! CLU048-1818 looking like quite the buy.

Any comparable sheets with 3500k spectrum?
4 not going to be enough for a 2'x4' single plant setup? Don't mind buying more if needed. Want to grow a dense buds.

HydroRed said:

My lights were joining the "Flintstone Era" before I even got done with them haha

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Mine aren't obsolete... yet.

ttystikk said:

My, my, what a difference a year makes.

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you aint seen nothing yet