Is 30" tall enough for COBS? If so please advise on my build.

Hello

The area of my cabinet is almost 4 square feet (28" x 20") but it is only 34" tall. I want to run 2 x CLU048-1818 or 2 x Vero 29 (50volts) at 80 watts each for a total of 160 watts which should give me over 900 ppfd. Heat sinks are going to be Alpine 64 or 11(cheapest) . I plan to get 3500K 80CRI (maybe 3000K).

1- Is my cabinet tall enough for COBS?
2- What reflector should I use if I go with Vero.

***at first, since I am on a tight budget, I wanted to use a single CLU058-1825 and run it at 140 watts***
3- This is bad idea, right?
4- Assuming it is not a bad idea, is the alpine 64/11 enough for cooling it since it will be less than 90 heat watts?


Thanks in advance for your advice and please excuse my English, it is not my mother tongue.

id go with boards/2' strips at that height

9 pieces-560mm- 21.7v LED Strips- 3000K Bridgelux EB Series (BXEB-LO560Z-30E2000-C-A3) Arrow Electronics $7.31 USD each= $65.79 USD before tax.
1 piece- 150w LED Driver- Meanwell HLG-120H-C700B: 215v at 700ma- from Arrow electronics $42.80 USD.
This 150w driver will run the 9 strips, in series, at the nominal current of 700ma requiring no heatsinking. In my opinion, at just under 40w per square foot, providing ample photon output to illuminate that space adequately.
Look at the Bridgelux EB series threads.

Thank you guys. I guess I have to do more homework and start reading about boards. I will post back my final setup.

I'll second @Chip Green on the EB strips... but mix them 3000K 3500K 4000K (light on the 4000K)
and you shouldn't out grow the height. Was too heavy on the 4000K, selected plants for shortness, and
they didn't even reach the scrog net level I had planned. So dense and frosty, just not a big plant.
Number 1 was 15 grams dried... the current one possibly more when dried...

The new Gen 2 strips are more efficient, Digikey's estimated ship date is 12/23.

Yes, I went to bridgelux site and saw that gen 2 is 180 lm/w over 159 lm/w gen 1. I will try to get the gen 2 version.

HalfBee said:

I'll second @Chip Green on the EB strips... but mix them 3000K 3500K 4000K (light on the 4000K)
and you shouldn't out grow the height. Was too heavy on the 4000K, selected plants for shortness, and
they didn't even reach the scrog net level I had planned. So dense and frosty, just not a big plant.
Number 1 was 15 grams dried... the current one possibly more when dried...

Click to expand...

I thought that light in the 4000k will make my plants go taller because of the extra blue. I couldn't find the graph for 3500k.

No, the extra blue will reduce stretch. Deeper/more red will increase stretch.

Vehlor said:

Hello

The area of my cabinet is almost 4 square feet (28" x 20") but it is only 34" tall. I want to run 2 x CLU048-1818 or 2 x Vero 29 (50volts) at 80 watts each for a total of 160 watts which should give me over 900 ppfd. Heat sinks are going to be Alpine 64 or 11(cheapest) . I plan to get 3500K 80CRI (maybe 3000K).

1- Is my cabinet tall enough for COBS?
2- What reflector should I use if I go with Vero.

***at first, since I am on a tight budget, I wanted to use a single CLU058-1825 and run it at 140 watts***
3- This is bad idea, right?
4- Assuming it is not a bad idea, is the alpine 64/11 enough for cooling it since it will be less than 90 heat watts?


Thanks in advance for your advice and please excuse my English, it is not my mother tongue.

Click to expand...

Strips would be much better suited for that size. and LST, LST, LST.

nevergoodenuf said:

No, the extra blue will reduce stretch. Deeper/more red will increase stretch.

Click to expand...

Oh, I missunderstood that then. In that case, shouldn't I use all 4000k instead since I don't have a lot of height? I know red is good for flower but 4000k still have plenty of red I think. Maybe 5x4000k and 2x3000k.

Vehlor said:

Oh, I missunderstood that then. In that case, shouldn't I use all 4000k instead since I don't have a lot of height? I know red is good for flower but 4000k still have plenty of red I think. Maybe 5x4000k and 2x3000k.

Click to expand...

4000K works great for both Veg and Flower.

Chip Green said:

9 pieces-560mm- 21.7v LED Strips- 3000K Bridgelux EB Series (BXEB-LO560Z-30E2000-C-A3) Arrow Electronics $7.31 USD each= $65.79 USD before tax.
1 piece- 150w LED Driver- Meanwell HLG-120H-C700B: 215v at 700ma- from Arrow electronics $42.80 USD.
This 150w driver will run the 9 strips, in series, at the nominal current of 700ma requiring no heatsinking. In my opinion, at just under 40w per square foot, providing ample photon output to illuminate that space adequately.
Look at the Bridgelux EB series threads.

Click to expand...

Can you really run theses strips without any heat sink @700 ma? I mean could I mount them to a piece of plywood ? How does this effect the life of the strips?

Chip Green said:

9 pieces-560mm- 21.7v LED Strips- 3000K Bridgelux EB Series (BXEB-LO560Z-30E2000-C-A3) Arrow Electronics $7.31 USD each= $65.79 USD before tax.
1 piece- 150w LED Driver- Meanwell HLG-120H-C700B: 215v at 700ma- from Arrow electronics $42.80 USD.
This 150w driver will run the 9 strips, in series, at the nominal current of 700ma requiring no heatsinking. In my opinion, at just under 40w per square foot, providing ample photon output to illuminate that space adequately.
Look at the Bridgelux EB series threads.

Click to expand...

Can I run these strips in parallel? I know that I can run cobs in parallel, specially with active cooling. I just dont feel confortable working with that many volts.

Vehlor said:

Oh, I misunderstood that then. In that case, shouldn't I use all 4000k instead since I don't have a lot of height? I know red is good for flower but 4000k still have plenty of red I think. Maybe 5x4000k and 2x3000k.

Click to expand...

Digikey is only going to carry the 3500k and 5000k The Gen 2 as a reg stocked item. The min order for the other strips are
28cm min 400
56cm min 200
112cm min 100
Cheers
CCG

They are fine with out a heat sink at 700mA/nominal current. I'm not sure about mounting to plywood, it would tend to insulate the back side of the strip.

They can be run parallel just like cobs. The wiring method has nothing to due with cooling.

I think it was BuddyColas who taught me about Voltage droop. Search the "Bridgelux EB series build" thread for that term...

My 700ma versions(15x 560mm 3000k) NO heat removal at all, have 1.1% droop,built on wooden frames (2"x2" pine lumber), look like ladders, no backing, strips attached with 2 screws, 1 on each end....
My 1050ma versions (10x 560mm 3500k) are fastened to a "bed" of aluminum rollstock (sometimes called flashing) those get 1.5% droop....

The rollstock I use can be cut with medium duty scissors....

Ive never had a strip test any warmer than 130f, and that's with ZERO air movement, when the circulation is added, those temps drop far enough for me to never care about them...

As far as lifespan, I have no clue what to expect. I'm satisfied with the voltage droop range, tend to believe I'm causing no harm to the diodes. Even if I am, the technology will advance enough to upgrade before I burn them up.

Well, if I can wire them in parallel, then I am definitely doing that and use a meanwell hlg-150h-20.
Even though bridgekux states that no heatsink is needed, I'm still mounting this in aluminum bars, plywood sounds like a bad idea

Well, I ended up buying the following from from arrow electronics:


9 x BXEB-L0560Z-30E2000-C-A3 ($7.32 each)
1 x HLG-185H-24A ($46.60)

10% off and free 2 days shipping. Total was $108.29. I can't believe it!!!

Only problem with that driver is that it only goes down to 22v so I can under-drive the strips only to around 650ma (I guess), but I figure that since I am running in parallel, I can always unplug a couple of strips if I have too much light. Now all I have to do is get a cheap aluminum sheet and have fun.

Thank you guys for the help. I'll post pictures as soon as light is done.