Cheap and Cheerful DIY using Citizen cobs

Evil-Mobo

Well-Known Member
Thanks! And yeah, I built two to go in a 4x2 space.

Honestly even cheaper and more cheerful would be stepping up to an HLG-185 for like $4 more, and maybe some of the $12.50 Mechatronix mega heatsinks. That would give an extra 50W for $14 more, and a bit more weight. If CDI had those heatsinks in stock I probably would have.

I built this around what I could get ahold of without a six week wait, but things are only going to get easier to build and buy.
How many 3070's could I run with a mean well HLG-240H-C1050B?
 

BOBBY_G

Well-Known Member
I can try to write something up, although now that you opened that can of worms with the "subforum changing the world" thread, it shined a glaring, duh moment light on how crippling it is not to be able to edit/curate top posts with the up-to-date information around here. There was no good explanation given, and "just ask a mod" to edit posts, update images, all that crap, is a poor excuse for a solution.
im sayin. ive said some stupid inaccuate shit back when i got started and it pains m that other people are attempting to build knowledge off of that
 

BOBBY_G

Well-Known Member
This is a great thread @JorgeGonzales
I have a general cob question and a lot of those in the know are in your thread so hopefully I can ask it here:
Where are all of these cobs being produced seeing usage besides grow lights? Are they starting to show up in large numbers in consumer / commercial products?
Most applications appear to be in high bay warehouse, stadium, and streetlighting
 

BobCajun

Well-Known Member
So, this is my first cob build, but not my first DIY light. I built to a modest budget, and chose Citizen over Vero 29s after crunching the numbers and realizing Citizen is way ahead of Bridgelux at the moment, likely because they are a generation ahead right now.

These are a minimalist design, meant to be easy to build in modular chunks, with aluminum angle, pre-drilled heatsinks, and hand tools.

The parts for one lamp, not including screws and wire:

4x Citizen CLU048-1818 $100
1x Meanwell HLG-120H-C700B $52
4x Mechatronix 9980 Xtra heatsinks $38
4ft 3/4 x 1/8 aluminum angle $10

Total with CLU048-1818: $200

Draws 160W at the wall, ~167lm/W @ 3500k

Same build with CLU048-1212 would be $150, and ~160lm/W. 1212 is a great deal, if it was easily available. It isn't. This type of build would work fine with anything smaller than a 3590, like a CXB3070 or Vero 29.

I wanted one cob per square foot, so with the heatsinks that ended up being two 16" and two 12" lengths of aluminum angle, in an H shape like so:

View attachment 3684362

Honestly, single rivets and a dab of epoxy would have been just as effective as two screws in preventing slippage. I just wanted to be able to dismantle if I forgot anything, but it all went together fine.

Then the heatsinks, which I attached with two thread rolling M4 bolts each. The holes are already drilled in the heatsink for a different cob holder. Test fitting the driver as well. The HLG-120H is a perfect fit for the 12" spacing.

View attachment 3684368

And the hard part was over at that point. I only snapped one bolt head, which is pretty good for me.

Skipping to the finished light, I used solid core wire. If this was something that would be flexed a lot or taken apart and put back together a lot, no way. But I wanted something that stayed neat without being fussy, so it was perfect here.

Editing to add, I forgot to mention the wire routing holes were sanded smooth to prevent wear on the insulation. Alesh shows safer and potentially neater routing aids here https://www.rollitup.org/t/cheap-and-cheerful-diy-using-citizen-cobs.909460/#post-12606160

View attachment 3684373

View attachment 3684374
View attachment 3684371

Love these cob holders. I ordered the Ideal to try as well, but they were fiddly as hell, and these allow an Angelina to attach directly.

The only other interesting bit is the switch. A bit of magic with some resistors and a DPDT on-on-on, and et voila:
View attachment 3684378
View attachment 3684376

Basically just putting one or two 24k resistors in series, using crap I had around the house. The 100% setting is an open connection between the dim wires, so it runs about 10W over the 150W it pulls with a 100k resistor.

And that is about that. Some more pictures:

View attachment 3684390 View attachment 3684393

View attachment 3684395
A good choice of components. Only thing I would have done differently was to get the opaque metallic 60 degree Angelinas instead of the translucent 90 degree. Not much point lighting the walls with those translucent ones. You would get another 6% efficiency. You wouldn't need a 90 degree spread with a single COB anyway. With a high bay, yes. With one COB, you might as well get a fairly tight beam so you can position the light higher above the plants and still get good intensity. Just a suggestion. Whatever works for you.
 

JorgeGonzales

Well-Known Member
A good choice of components. Only thing I would have done differently was to get the opaque metallic 60 degree Angelinas instead of the translucent 90 degree. Not much point lighting the walls with those translucent ones. You would get another 6% efficiency. You wouldn't need a 90 degree spread with a single COB anyway. With a high bay, yes. With one COB, you might as well get a fairly tight beam so you can position the light higher above the plants and still get good intensity. Just a suggestion. Whatever works for you.
You shared your opinion before I built, I'm not sure why you think I would change my mind now.

I'm not using a single cob, and have no idea where your 6% figure comes from. In BJB versions the metalized 60 degree reflector is 3% less efficient than the translucent 90 degree reflector, according to Ledil.

You might have argued that 60 degrees would need less height adjustments overall, because it will, but it's also harder to source, more expensive, and I liked what I saw from actual measurements made at 12 and 18" by @robincnn, and a bird in the hand and all that.

But I'm happy to discuss. Just think we already did.
 

BobCajun

Well-Known Member
You shared your opinion before I built, I'm not sure why you think I would change my mind now.

I'm not using a single cob, and have no idea where your 6% figure comes from. In BJB versions the metalized 60 degree reflector is 3% less efficient than the translucent 90 degree reflector, according to Ledil.

You might have argued that 60 degrees would need less height adjustments overall, because it will, but it's also harder to source, more expensive, and I liked what I saw from actual measurements made at 12 and 18" by @robincnn, and a bird in the hand and all that.

But I'm happy to discuss. Just think we already did.
Oh, I can't actually remember who I discussed what with most of the time. Sorry for repeating then. The 6% figure came from the pdf for the Angelina line. It says those white ones are 94% efficient and the metallic ones are 100%. You can see light's coming through the sides, right? Those aren't actually made for directing all the light down. Granted that little bit of loss won't make a huge difference. Just seems a little wasteful, that's all.



 

JorgeGonzales

Well-Known Member

BobCajun

Well-Known Member
100% efficiency should set off the bullshit meter, that's all I know.

Actually, efficiency looks like it changes based on...something. Holder geometry?

http://www.farnell.com/datasheets/1850839.pdf
http://www.mouser.com/ds/2/229/13839-Ledil-datasheet-879954.pdf


Best I could do, but overall the metal version is a little less efficient, no matter what your eyes tell you, if you trust Ledil. After that 100% efficient claim I'm not sure I do!
Well the 100% was simulated. It would seem that a reflector that has a metallic inner surface is going to reflect more light downward than a translucent white one. That data sheet did show slightly lower efficiencies though, so apparently no advantage, weird.
 
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Budzbuddha

Well-Known Member
So who is the source for these cobs ?
And what would be a better replacement for a 3590 ( 3500k ) ?
Im at the point of my build where all i need is the cobs.
5) cob 3500k
Meanwell 185 1400b / lpc 60 1400

image.jpg

Love this thread - any suggestions appreciated :leaf:
 

benbud89

Well-Known Member
Great stuff, Jorge. You do a really nice job building and sharing your info. I always thought you were a douche with your sarcastic comments in other threads, but really nicely done!
 

thetr33man

Well-Known Member
So who is the source for these cobs ?
And what would be a better replacement for a 3590 ( 3500k ) ?
Im at the point of my build where all i need is the cobs.
5) cob 3500k
Meanwell 185 1400b / lpc 60 1400

View attachment 3685402

Love this thread - any suggestions appreciated :leaf:
https://led.cdiweb.com/ProductDetail/CLU0481818C4303H5K2-citizen/590991/

They came out recently with their 5th gen cobs , youll see the lumen/watt is kinda low on this chip, but its 90 cri with a nice red amount, so while the lumens (green heavy) is lower, should be a good veg+flower chip.
 

JorgeGonzales

Well-Known Member
So who is the source for these cobs ?
And what would be a better replacement for a 3590 ( 3500k ) ?
Im at the point of my build where all i need is the cobs.
5) cob 3500k
Meanwell 185 1400b / lpc 60 1400

View attachment 3685402

Love this thread - any suggestions appreciated :leaf:
The source is the problem, there isn't one. Which is really too bad because they have a complete line of cobs suitable for our purposes from $10-60, that are class leading in a lot of ways, both price and performance.

Great stuff, Jorge. You do a really nice job building and sharing your info. I always thought you were a douche with your sarcastic comments in other threads, but really nicely done!
Why can't I be both?
 

JorgeGonzales

Well-Known Member
@JorgeGonzales hey man, is this the BJB holder that you used to direct fit the
MODULED XTRA 9980-B

BJB GmbH & Co. KG: LED COB Connector: 47.319.2033.50
You know, funny you mentioned that. That confused both me and the CDI sales rep trying to help me figure it out, but I think they both work. The 47.319.2030.50 is what I ended up using, since they are in stock for a buck.

Looks like the only difference is (minimum?) wire size:

http://www.bjb.com/index.php?pid=347545&lid=4
http://www.bjb.com/index.php?pid=398478&lid=4
 

BuddyColas

Well-Known Member
So, this is my first cob build, but not my first DIY light. I built to a modest budget, and chose Citizen over Vero 29s after crunching the numbers and realizing Citizen is way ahead of Bridgelux at the moment, likely because they are a generation ahead right now.

These are a minimalist design, meant to be easy to build in modular chunks, with aluminum angle, pre-drilled heatsinks, and hand tools.

The parts for one lamp, not including screws and wire:

4x Citizen CLU048-1818 $100
1x Meanwell HLG-120H-C700B $52
4x Mechatronix 9980 Xtra heatsinks $38
4ft 3/4 x 1/8 aluminum angle $10

Total with CLU048-1818: $200

Draws 160W at the wall, ~167lm/W @ 3500k

Same build with CLU048-1212 would be $150, and ~160lm/W. 1212 is a great deal, if it was easily available. It isn't. This type of build would work fine with anything smaller than a 3590, like a CXB3070 or Vero 29.

I wanted one cob per square foot, so with the heatsinks that ended up being two 16" and two 12" lengths of aluminum angle, in an H shape like so:

View attachment 3684362

Honestly, single rivets and a dab of epoxy would have been just as effective as two screws in preventing slippage. I just wanted to be able to dismantle if I forgot anything, but it all went together fine.

Then the heatsinks, which I attached with two thread rolling M4 bolts each. The holes are already drilled in the heatsink for a different cob holder. Test fitting the driver as well. The HLG-120H is a perfect fit for the 12" spacing.

View attachment 3684368

And the hard part was over at that point. I only snapped one bolt head, which is pretty good for me.

Skipping to the finished light, I used solid core wire. If this was something that would be flexed a lot or taken apart and put back together a lot, no way. But I wanted something that stayed neat without being fussy, so it was perfect here.

Editing to add, I forgot to mention the wire routing holes were sanded smooth to prevent wear on the insulation. Alesh shows safer and potentially neater routing aids here https://www.rollitup.org/t/cheap-and-cheerful-diy-using-citizen-cobs.909460/#post-12606160

View attachment 3684373

View attachment 3684374
View attachment 3684371

Love these cob holders. I ordered the Ideal to try as well, but they were fiddly as hell, and these allow an Angelina to attach directly.

The only other interesting bit is the switch. A bit of magic with some resistors and a DPDT on-on-on, and et voila:
View attachment 3684378
View attachment 3684376

Basically just putting one or two 24k resistors in series, using crap I had around the house. The 100% setting is an open connection between the dim wires, so it runs about 10W over the 150W it pulls with a 100k resistor.

And that is about that. Some more pictures:

View attachment 3684390 View attachment 3684393

View attachment 3684395
Well researched and well done on the build! I like that the driver stiffens up the build...very simple elegant design. Thanks for sharing.
 
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Greengenes707

Well-Known Member
They make 3 bjb's for the 3070 now. Which I'm pretty sure is for citizen chips too.
-The original(no chip lock, and 20g or less wire)
-One that is the same as the original but with the chip lock feature.
-The best one imo, that takes bigger wire and has the chip lock feature.

The new one just came out late last year/early this year.
 

JorgeGonzales

Well-Known Member
They make 3 bjb's for the 3070 now. Which I'm pretty sure is for citizen chips too.
-The original(no chip lock, and 20g or less wire)
-One that is the same as the original but with the chip lock feature.
-The best one imo, that takes bigger wire and has the chip lock feature.

The new one just came out late last year/early this year.
Sounds right to me, if the chip lock feature is the plastic posts that fit in the mounting holes on the cob. 2030 must be the middle one, 2033 the last.
 
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