First Time DIY COBS builder

Bachomp

Well-Known Member
I'm trying to find these cobs
CXB3070 BB @3000k
I can't seem to find that they exist. However I can find them @3500k. But would that really be better than running another style bin at 3000k.? I'd like to keep it relatively simple. Dimming my light etc seems like an unnecessary luxury..
Dimming isn't a luxury is allowing you to not run your driver's at 100% for that 1050ma. 3500k is what you want if your using the same fixture for veg and flower.

Also I'm using 4 CXB3590S on a 185c-1400 driver in a 2.5x2ft setup. 2 COB per heatsink passive cooled and the hottest spot I've seen gets to 90f. If your looking for simple id suggest not using 8 heatsinks.
 

rickymac21

Well-Known Member
Dimming isn't a luxury is allowing you to not run your driver's at 100% for that 1050ma. 3500k is what you want if your using the same fixture for veg and flower.

Also I'm using 4 CXB3590S on a 185c-1400 driver in a 2.5x2ft setup. 2 COB per heatsink passive cooled and the hottest spot I've seen gets to 90f. If your looking for simple id suggest not using 8 heatsinks.
Thanks for the post .
This light fixture will only be used for flower.
You suggest just using 2 heatsinks then. 4 on each one? So I would replace my heatsink fan combo from arctic cool with fewer larger fans to cool the 2 heat sinks.


As for the dimming. If those drivers would be running 100% I don't see why they were suggested. How would that be more effecient than running larger drivers not fully loaded?

I understand it might be upsetting for some people to come on here and see the same questions over and over. I see it too. But this is gibberish to me. And it seems everytime I think I get it figured out, I read new information, or get new suggestions for what equipment to use. So I do apologize.
 

Rahz

Well-Known Member
It would be better than another bin at 3000K. I prefer 3500K myself.

Dimming isn't that complicated and using the larger drivers will cost less than using a driver for each chip.
 

Rahz

Well-Known Member
Cutter also has the 3000k ad bin.
Good point. The AD bin is the top 3000K bin.

How would that be more effecient than running larger drivers not fully loaded?
The HLG series drivers operate around 94% efficiency and would be fully loaded at full bright. The ones you had picked out run at 85% efficiency at full load, but since they are 60 watt drivers running cobs at 50 watts, not fully loaded.
 

Symbolic

Member
I intend to build a light fixture for a new grow.
The space will be small (2'x4' foot print) but I plan to use 8 cree 3070's to get max penetration and light spread.

- 8 cxa3070-0000-000N0Z430H
- 8 Arctic cool Alpine 11 plus cooler fans
- 8 Meanwell LPC-60-1400 drivers
-(1) Meanwell plc-30-12 driver ??? (To power the fans/coolers)
-18 gauge wire for wiring everything needed
-20"x40" white mdf/particall board (mount for fans and Cobs)

Just a couple questions before I start making purchases.
1.) Will the meanwell plc -30-12 driver be sufficient enough to power the fans I listed? The fans only draw .16amps a piece I believe, so all together it would seem to stay under the drivers max output of 2.5amps.
2.) Any recommendations for connection blocks to wire the cob drivers together? Also probably a similar block for wiring the fans together. Or would I be just fine soldering all wires together in parallel and using heat shrink wraps around those connection points.

3.) Am I going overboard with the 8 Cobs in my space? I'd just like to ensure I have optimum coverage. Will be going s.o.g. setup this time so plant height will be minimal.

I know I can find most of this information , in fact I've probably read it a dozen times. I'm just new to the l.e.d. scene in general, let alone diy fixtures. So I'm seeing a lot of information but still having a hard time determining what's best for my application. Any tips or additional supplies recommendations are welcome. Thanks !
Not overkill, but def at ur max watt/sqf -- w/ ur 2' x 4' that put u @8sqft so if ur run ur lights at 1.4A ur puting out 50w/sqft

if u run them @ 1A now u are at 35w/sqft.. which is still over 25 and from what i hear u are n great shape!

@edit this guy https://www.rollitup.org/t/my-150w-vero29-tent.892059/page-3 is running 3 51w COBs at 1.4A w/ 30w/sqft and having amazing growth even n veg.. there is a diminishing return.. and i think after 50w/sqft u are hitting that return!

hope this help!
 
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rickymac21

Well-Known Member
Good point. The AD bin is the top 3000K bin.



The HLG series drivers operate around 94% efficiency and would be fully loaded at full bright. The ones you had picked out run at 85% efficiency at full load, but since they are 60 watt drivers running cobs at 50 watts, not fully loaded.
Great info and I appreciate the links to these other cites.
So the AD bins And BB bins, I could use either one of those with the MW hlg-185-1400 drivers and operate at similar watts. The only difference between the two would be the light itself, 3000k or 3500k. ???
I'm still leaning towards 3000k (so 3070AD bins) simply because this will be a flower only fixture.

So I guess since I have that cleared up and some good links to purchase from, would it be possible for someone to guide me to a link with a wiring diagram for wiring the cobs to the drivers, and wiring the drivers together to the power cord.??
It was my understanding that with each cob having its own driver I cold wire in parallel, which is super easy.
But with 1 driver running multiple lights, I'd have to wire in series to run them properly, correct? Now I understand that part as I have some experience wiring several different subwoofers in different ways to achieve a desired "ohm" operation from the amplifier. I'm not sure if the same thing apply s here.
Like I said, if someone happens to have a wiring diagram of a similar setup that would be fantastic, I can read the info all day, but seeing a visual really helps to understand it.
 

Rahz

Well-Known Member
Flower only, 3000K AD is a good choice.

Wiring multiple cobs in series to the HLG drivers is as simple as connecting the + lead from the driver to the positive pad on the cob. Negative pad on the cob goes to the positive on the next cob and so on til the last negative pad wires to the - lead on the driver. I don't have an image handy, but it's really that simple.

If you want to wire 2 drivers to a power cord it can be done with 3 Wago222-413, or solder and wrap the leads, or just use some wire nuts. Wagos are really nice and are cheap.

If you get the B series HLG drivers, same price and if you decide to wire up a dimmer at some point you can do so, though not adjustable without adding resistance (potentiometer or a resistor).

If you get the A series driver they are adjustable via a screw. You wouldn't be able to hook up a dimmer but you could still adjust the current.
 

grouch

Well-Known Member
This post gives a couple good bar graphs to help compare color temps. I believe it shows the cxb3590 series but it is pretty much the same for cxb3070.

UPDATE

These are CXB3590
Got the numbers from http://www.cutter.com.au/proddetail.php?prod=cut2809 and threw them into a spreadsheet for a visual comparison
Unfortunately all they had numbers for were 3000, 3500, 4000 and 5700k

I dropped 700+ IR because it's more of a trigger than growth contributor

Added 5700k

Keep in mind they measured from less than 8 inches

View attachment 3610424
View attachment 3610432

View attachment 3610425
View attachment 3610433
 

rickymac21

Well-Known Member
I knew I joined this forum back in the day for a reason... I can't thank you all enough for the help. I'm looking forward to putting this thing together and seeing the results.
I think I will end up getting the 'A' series of that driver, I like the idea of simply turning a screw to lower the amperage.
 

grouch

Well-Known Member
I knew I joined this forum back in the day for a reason... I can't thank you all enough for the help. I'm looking forward to putting this thing together and seeing the results.
I think I will end up getting the 'A' series of that driver, I like the idea of simply turning a screw to lower the amperage.
Should work great, can't wait to see it
 

rickymac21

Well-Known Member
@grouch @Rahz

I've got one more question to run by you guys. :roll:

Since I'm going to toss the multiple fan idea and just use 2 solid heatsinks (1 per 4 cobs) I'm now looking for an adequate driver for the new fans.

I found someone using these...
http://www.amazon.com/Prolimatech-Blue-Vortex-14-Fan/dp/B0045FE3V8

I would like my heat sinks to be long enough to disperse the cobs across the whole 4' foot print.
So I'm thinking (2) 42"x4.85" heat sinks would do what I want. With that length I can place a cob directly over each square ft section of my 2'×4' space.
These are the heat sinks I found.
http://www.heatsinkusa.com/4-850-wide-extruded-aluminum-heatsink/

So the questions are.
1. Would one fan per heat sink (see links above) adequately cool the sinks and cobs?
2. If so, what driver would be sufficient for those 2 fans? Am I still looking at the APV 25 12?
 

Rahz

Well-Known Member
I would go with 2 fans on each sink. You could put them all (.2 amps each) on an APV-12-12 but wouldn't hurt to use 2 of them, one for each sink to clean up the wiring, or split the power of each between the two sinks so if a fan driver ever fails the sinks remain fan cooled.
 

Symbolic

Member
It would be better than another bin at 3000K. I prefer 3500K myself.

Dimming isn't that complicated and using the larger drivers will cost less than using a driver for each chip.
Whats reason for preferring 3500k? good for veg n flowering?
 

Rahz

Well-Known Member
Yea, the 3500K has close to 15% blue which is ideal for all stages of growth. With 3500K there's a little less bleed off in the +730 range but almost not worth mentioning.
 
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