What do I need for my DIY COB??

Airwalker16

Airwalker16

Well-Known Member
Okay, I'm not very good at all the electrical jargon. I was watching growmau5's, 6 part series and it inspired me to take the plunge and finally make my own light. I want to make 2 identical lights. I plan on using 2- 10"wide 44" long heatsinks to hold 8 CXB3590's each. (If i can get away with less width or length or if id need more, please let me know) I want to use a dimming potentiometer on both of them so I know I need a "B" style meanwell driver to have that capability. Really, the thing I dont understand are the drivers. Supra 1500w CXB3590 thread is AWESOME. I read about being able to run 8 of the cobs with the one driver at 64%. This is where I get lost. How do you, or what is it that does, control the percentage? I basically just want to know what driver I will need to purchase to run 8 CXB3590's on a 10"x44" heatsink?

Growmau5, I can't express enough how much confidence your videos gave me to just do it. So thank you. Also thank you to Supra and REALSTYLES for all your input.

One more thing- I plan on contacting the INFAMOUS Jerry at king brite for my cobs, lenses and holders. Now, does he sell the chip-lok holders, because that looks like the cleanest, easiest way to install these. Also, I'll use kapton tape to mount everything. Not the best looking option I know, but from what I've read, it's very efficient and can hold the weight of the COB, Holder, and Lens with no problem.

Also, if you have links to the best places/places you've gotten your parts from personally, let me know. I understand this basically:

COBs, lenses, holders- king brite
Heatsinks- heatsinkusa.com
Drivers- meanwell.com
Holders- newark.com
Reflectors for cheap(angela,angelina)- I have NO Idea.


So any input/answers would be so appreciated as the whole DRIVER LINGO is like French to me. ;)

-Jordy
 
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African420

African420

Member
you can get the cobs and drivers, reflectors everything from kingbrite, i got my quote this morning from Jerry at KB

only your heatsinks and holders must be sourced elsewhere as per your links :)
 
Airwalker16

Airwalker16

Well-Known Member
I REALLY wish I understood the aspect of drivers, and how to know what they can run, the differences between them all, wattage and Amps, efficiency percentages as how to achieve them, and everything else that's second nature to so many of you.

I want to build a light so bad. I bought a 4 COB gogreen I'm using now but I want to build a 16 cob for flower.
 
Airwalker16

Airwalker16

Well-Known Member
I understand the forward voltage is equivalent to the output of the driver so that you can see how many can run on a single driver. But this post from supras:

@64%
(8 )CXB3590 3500K CD @ 700mA (23W ea) $380
(1) HLG-185H-C700 $65
184 dissipation W ->66W heat ->
passive cooled heatsink 7920cm² -> 4.23"X44" $68 (could split these into 2 or 4 units)
or
active cooled heatsink 2640cm² -> 3.5"X36" heatsink (for spread) $45 + 80mm fan + psu $10
active cooled heatsink 2640cm² -> 1.8"X44" heatsink $34 + 80mm fan + psu $10
(8 ) lenses $32
117.8 PAR W covering 6ft² = 879 PPFD
117.8 PAR w covering 7ft² = 754 PPFD
$545 = $4.63/PAR W passivecooled


Is what is confusing me. The cobs are still 36fv right? How can I run 8 CXB3590S on one 700ma driver? And how is the wattage only 23w?
But this is the basis of my idea to build an 8 cob cxb3590. As he says it's the best setup in his opinion.
 
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jewbag

jewbag

Well-Known Member
you have to purchase a driver that matches the current you want to run your cobs at. so, you can choose between hlg c700, c1050, c1400, etc. these different drivers have different outputs/max voltages, with the lowest current driver having the greatest output. therefore the 700ma driver can run the most amount of cob's. additionally, the lower the current of the driver the lower wattage your cob's will run. According to ohm's law, fv*i ~ w, and 32.9v*0.7a ~ 23w. at 1400ma this becomes 34.9v*1.4a ~ 48.8w. the hlg-240h-c700 can run (10) cxb3590 36v, the 185h can fit 8. also rewatch the first episode of @Growmau5's series because he explains this pretty clearly.
 
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Airwalker16

Airwalker16

Well-Known Member
I just watched it about 3 times. Haha. That's why I'm Cinfused. It's slowly making sense though. I know more after today then I did my entire life.
 
alesh

alesh

Well-Known Member
You need either a reflector or a lens. Not both. I'd avoid using kapton with lenses and/or lenses and use holders instead. But if you choose to use kapton, you don't need COB holders.
Also consider Cutter as an option.
 
Airwalker16

Airwalker16

Well-Known Member
I'm sure I could drill and tap it wouldn't be that hard. Kapton just seems so much simpler. What's the hype about cutter?
 
alesh

alesh

Well-Known Member
Airwalker16 said:
I'm sure I could drill and tap it wouldn't be that hard. Kapton just seems so much simpler. What's the hype about cutter?
Click to expand...
They seem to have competitive prices and all the components DIYers use. I ordered from KB in the past and I was satisfied.

Kapton seems simpler but I don't see it as a convenient method with optics.
 
F

flexy123

Well-Known Member
It's actually "relatively" simple with the drivers.

Look up the specs of the COBs, say, the CXB3070 or CXB3590. The CXB3070 in general are run under-driven at 50W.
So if you have a fixture with 4 lights you want to run a 50W, you need a 200W driver.
(In this case for 50W per COB you run them 36Vx1400mAH), so the driver must be 1400mAh and 144V (36V x4), assuming you have the 36V LEDs. (Watts = V*Amps)

CXB 3590 you can also run at 1400mAh but personally I think it makes more sense to run them at 1600-1750mAh, is 36Vx1750mAh == 63W for each 3590. Fixture with 4x 63 = 252W, in this case you'd want a 250W driver that can provide 1750Mah.

* This means also if you want to run COBs at 50W (or 60ish for the CXB3590), usually ONE driver can be good up-to 4 COB, more COBs = more drivers. Eg. fixture with 8 COBs 2 drivers.

TLDR: Check COB specs, think at what W you want to run each COB and what W makes sense, this will tell you what type of driver(s) you will need.
 
F

flexy123

Well-Known Member
>>
How can I run 8 CXB3590S on one 700ma driver? And how is the wattage only 23w?
>>

You can run the COBs at whatever wattage you want, I personally would not want to run CXB3590 at only 23W. (Mind you their max is 137W, correct me if I am wrong). But of course if you want to run them very cool etc. you can do that, except of course you need more COBs for the same light as if you were to run them at say, 1400mAh.

36V*700mAh = 25W
8x25W = 200W
8x36V=288V

HLG-185H-C700 works since it can provide 700mAh and 286V.
Whether this setup makes sense, I am not 100% sure. As said a little too under-driven for my taste.
 
F

flexy123

Well-Known Member
Airwalker16 said:
I'm sure I could drill and tap it wouldn't be that hard. Kapton just seems so much simpler. What's the hype about cutter?
Click to expand...
I really didn't want to do that, not wanting to spend $40-$50 on a heatsink and then (literally) screw it up. This is why I let the light build by someone. However, may well be that drill/tap in aluminum is child's play. I just never did it and didn't want to risk anything.
 
alesh

alesh

Well-Known Member
flexy123 said:
It's actually "relatively" simple with the drivers.

Look up the specs of the COBs, say, the CXB3070 or CXB3590. The CXB3070 in general are run under-driven at 50W.
So if you have a fixture with 4 lights you want to run a 50W, you need a 200W driver.
(In this case for 50W per COB you run them 36Vx1400mAH), so the driver must be 1400mAh and 144V (36V x4), assuming you have the 36V LEDs. (Watts = V*Amps)

CXB 3590 you can also run at 1400mAh but personally I think it makes more sense to run them at 1600-1750mAh, is 36Vx1750mAh == 63W for each 3590. Fixture with 4x 63 = 252W, in this case you'd want a 250W driver that can provide 1750Mah.

* This means also if you want to run COBs at 50W (or 60ish for the CXB3590), usually ONE driver can be good up-to 4 COB, more COBs = more drivers. Eg. fixture with 8 COBs 2 drivers.

TLDR: Check COB specs, think at what W you want to run each COB and what W makes sense, this will tell you what type of driver(s) you will need.
Click to expand...
Just FIY, mAh (milliampere-hour) is unit of electric charge (1 mAh = 3,6C). Electric current is measured in (milli)amperes - (m)A.
 
Airwalker16

Airwalker16

Well-Known Member
And my question got lost in a sea of replies haha. But how many drivers can be plugged Into one grounded 3 prong US wall cord?
 
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