DiY LED - Cree CXA3070

hayrolld

Well-Known Member
Can I run a single CXA3070 with a 100W dimmable constant current driver (AC to DC30-36V 3000mA), if it were dimmed to say 25%-45% and NEVER exceeding 50%? I know the 3000mA is a killer, but if the driver is dimmed below 45% would that suffice? Also, then I would have some power in the driver if I ever wanted to upgrade.

Secondly, would I be able to run 2 CXA 3070 with the driver running full? I've read that the voltage has to be doubled or something if you want to connect 2 chips to the same driver? Is this accurate?

I've done hours of research but cant seem to put all the pieces together.

Thanks all!

Here is the setup I am planning on purchasing...could this be a badass setup for the low price of $120+-

$48.00
http://www.aliexpress.com/item/Freeshipping-IP67-Waterproof-100W-Dimmable-Constant-Current-LED-Driver-AC-to-DC30-36V-3000mA-for-100W/828608854.html

$24
http://www.aliexpress.com/item/CPU-cooler-Two-8cm-fan-2-heat-pipes-Multi-platform-Radiator-socket-LGA775-1155-1156-754/32275859473.html

AB bin - $38.00
http://www.aliexpress.com/item/Freeshipping-1pcs-Cree-XLamp-CXA3070-led-74-117W-COB-EasyWhite-5000K-Warm-White-3000K-LED-Chip/2052849889.html

Thanks again!
That driver is not a good choice for what you want to do. Watts=amps X volts. To figure volts needed in a driver, find the cob's voltage forward and multiply by how many cobs you want to use. For cxa3070, Vf is 38.5volts for one, or 77volts for two. The driver you linked maxs out at 36volts, so not a good choice. If you want 25-45% of 3000ma, get a Meanwell hlg-120h-c1400 that is dimmable. It will cover the power range you want, and you can run up to three cxa3070s with it. Price should be close to what you were looking at. Please find and read the sticky thread on DIY LEDs - How to Power Them, this is all explained there and a better place for questions like this. It will help you figure out how to power and wire everything for your build.

Mod- not sure if its possible, but could my response and the previous post be moved to the DIY how to power thread please?
 

jimbob9

Active Member
Hi Guys/Gals,
I'm planning on building a light myself shortly.
Quick fan question, what do y'all think about using a Meanwell GS12U05-P1I to power 20 Arctic 11's?
http://www.mouser.com/ds/2/260/GS12U-spec-22957.pdf

From some previous reading, looks like the Arctic 11's pull roughly 70mA at 5V. This Meanwell's at 5V 2A, 76% efficient.
I'm planning on using CXB 3070's at 1400mA.
Thanks to all you DIY LED pioneers!
 

BruceLeeSkills

New Member
Hi guys,
new to the forum and thank you all for the valuable information.

Would you all say that currently, the cxb3590 is the way to go in terms of efficiency and output?
And if more on a budget and less emphasis on efficiency, running the vero29 hard would be the best option for a low initial investment but also high output?

The cob market moves so fast its hard to keep up!
 

Voidling

Well-Known Member
You have to decide on budget being upfront costs or running costs over time.

I'm having the debate between the vero line and the cxa3070. I'm aiming for 5,000 lumens per square foot. Meaning a single cxa3070 would give roughly 2sq ft. Or use couple vero to spread better and run two different temperature cobs.

Pricing 3.5" heatsink at 6" is the same cost as the arctic 11 when shopping is included since Amazon shopping is free. So may still run the arctics on vero 29 or 18
 

GrnZ32

Member
Hi guys,
new to the forum and thank you all for the valuable information.

Would you all say that currently, the cxb3590 is the way to go in terms of efficiency and output?
And if more on a budget and less emphasis on efficiency, running the vero29 hard would be the best option for a low initial investment but also high output?

The cob market moves so fast its hard to keep up!
Im pretty new to the cob technology but have done a lot of reading through members like Supra and others. I believe the consensus (and please someone step in if im wrong) is that the cxb3590 is potentially the most powerful and/or efficient cree cob on the current market. Their worth is determined by how much you drive them, what sort of coverage, and how much up-front cost your willing to spend. More up-front cost of running more lights at lower power reaps more benefits of better coverage, less heat waste meaning smaller electric bill, and better crop-out. how much is the diminishing returns on cost of this sort of light? i guess it matters how long till the next much more efficient jump in LED or other lighting technology...


As for myself im currently building 2 cxb3590 72v lights running on one meanwell HLG-120h-c1050a to get the 150watts out of two lights for under $200. The driver is dimmable so I can start on some seedlings I got cookin then amp it up for flower once i get more of em put together. Just waiting on my pk3 and kapton tape at the moment...
 
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BruceLeeSkills

New Member
Im pretty new to the cob technology but have done a lot of reading through members like Supra and others. I believe the consensus (and please someone step in if im wrong) is that the cxb3590 is potentially the most powerful and/or efficient cree cob on the current market. Their worth is determined by how much you drive them, what sort of coverage, and how much up-front cost your willing to spend. More up-front cost of running more lights at lower power reaps more benefits of better coverage, less heat waste meaning smaller electric bill, and better crop-out. how much is the diminishing returns on cost of this sort of light? i guess it matters how long till the next much more efficient jump in LED or other lighting technology...


As for myself im currently building 2 cxb3590 72v lights running on one meanwell HLG-120h-c1050a to get the 150watts out of two lights for under $200. The driver is dimmable so I can start on some seedlings I got cookin then amp it up for flower once i get more of em put together. Just waiting on my pk3 and kapton tape at the moment...
Basically running the same setup as you for a small space. Are you active/passive cooling? I'm still undecided after reading the other thread on this subject although I'm leaning more towards an active design. With a pot/dimmer I can turn it way down if a fan ever craps out on me.
What meanwell drivers do you guys recommend for driving 1 or 2 fans?
 

SupraSPL

Well-Known Member
Another option, if you are using single drivers (up to 60V), is a DC to DC converter added to the COB circuit. I have not tested this yet but seems promising

http://www.ebay.com/itm/DC-DC-Boost-Power-Converter-4V-34V-to-4V-60V-5V-12V-24V-48V-Adjustable-LM2587-/262001926576?hash=item3d008821b0

The simplest most electrically efficient option is passive cooling. With sufficient surface area, passive friendly profile and relatively low drive currents, temp droop can be in the 1-2% range. Passive is a lot more attainable now thanks to the very high efficiencies we are seeing now with top bin CXB3590s
 
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SupraSPL

Well-Known Member
Ran a few tests on the APV-12-12

140mm high rpm fan:
.325A 12V = 3.74W
power draw = 4.8W
efficiency = 78%
power factor = .4
so the system is drawing 3.2X more current than the fan is using, not bad relatively

80mm high rpm fan:
.167A 12V = 2W
power draw = 2.8W
efficiency = 71.6%
power factor = .42
drawing 3.33X more current than the fan is using, not bad relatively

140mm low rpm fan:
.123A 12V = 1.476W
power draw = 2.4W
efficiency = 61.5%
power factor = .54
drawing 3.1X more current than the fan is using, again not bad considering the PSU is running at 1/10 of max current
 
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alesh

Well-Known Member
Another option, if you are using single drivers (up to 60V), is a DC to DC converter added to the COB circuit. I have not tested this yet but seems promising

http://www.ebay.com/itm/DC-DC-Boost-Power-Converter-4V-34V-to-4V-60V-5V-12V-24V-48V-Adjustable-LM2587-/262001926576?hash=item3d008821b0

The simplest most electrically efficient option is passive cooling. With sufficient surface area, passive friendly profile and relatively low drive currents, temp droop can be in the 1-2% range. Passive is a lot more attainable now thanks to the very high efficiencies we are seeing now with top bin CXB3590s
Could be used with virtually any COB/driver combination with the exception being 70+V 3590s.
The converter has to be connected in parallel with one COB only of course.
schematics.jpg
 

Greengenes707

Well-Known Member
Ran a few tests on the APV-12-12

140mm high rpm fan:
.325A 12V = 3.74W
power draw = 4.8W
efficiency = 78%
power factor = .4
so the system is drawing 3.2X more current than the fan is using, not bad relatively

80mm high rpm fan:
.167A 12V = 2W
power draw = 2.8W
efficiency = 71.6%
power factor = .42
drawing 3.33X more current than the fan is using, not bad relatively

140mm low rpm fan:
.123A 12V = 1.476W
power draw = 2.4W
efficiency = 61.5%
power factor = .54
drawing 3.1X more current than the fan is using, again not bad considering the PSU is running at 1/10 of max current
Nice. Even at full current load it's almost the same figures...just tested apv12-12 vs 16-12 and got near identical characteristics wile running (6) .18a@12v fans.
Lower apparent power from the 16 actually.
 

PurpleBuz

Well-Known Member
Could be used with virtually any COB/driver combination with the exception being 70+V 3590s.
The converter has to be connected in parallel with one COB only of course.
View attachment 3481627
well that just flew over my head ! Can someone explain whats up in simpler terms ?

is this a buck driver that will allow us to run fans off of the constant current led driver ?
 

GrnZ32

Member
Basically running the same setup as you for a small space. Are you active/passive cooling? I'm still undecided after reading the other thread on this subject although I'm leaning more towards an active design. With a pot/dimmer I can turn it way down if a fan ever craps out on me.
What meanwell drivers do you guys recommend for driving 1 or 2 fans?
Im going active cooling with a alpine 64 plus CPU heatsink/fan each cob for easy setup and maneuverability. This will likely change when I plan the next light with more than just two cob led's. Heres my noob question - when i dim the driver and led's on my 72v cobs and 1050a driver does this in turn increase my LED efficiency or even decrease my dimmer efficiency somehow? wondering if i could just later rebuild a larger dimmable lamp with these same drivers and gain efficiency by dimming.
 

CanadianONE

Well-Known Member
The link you provided only has a single trim pot to adjust voltage, it doesn't have the second trim pot to limit current. Anyone going this route make sure to grab the boost converters with 2-3 trim pots. The third trim pot on three pot version is for voltage cutout for battery charging.
 
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