DiY LED - Cree CXA3070

kmog33

Well-Known Member
I wanted to check my thought process and make sure everything is right in my head, so anyone who knows feel free to jump in. I know you can run 4 CXB3590s 36v off an HLG 185/240 1400. So if I wanted to run 2 CXB3590s instead (smaller tent) I could either run 72v units with the HLG 1400 or 36v units with a HLG 700? Or will the HLG 185/240 1400 not support 72v? Am I thinking this through correctly?
You can use either the 36v or 72v cobs on either I think. Unless the output voltage is less than 72v...


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Symbolic

Member
Hello, first post here...

I jsut skimmed over this thread and found a lot of great info that has been bookmarked and copy pasted to sticky notes.

I crafted some LED panels n past around 2012, but life came and never really got to use them. I'm using them now a tent and they work well. Top bin reds/warmwhite/royal b/deepred


Quick question... what would I get n VEG results w/ 2x CXB3070s AD @ 1.4mA n a 3' x 2' tent? Is it recommended to veg w/ these?
-If not what is a great option for vegging?


Already understand the flower amazing well :>>

Cheers thanks for ur time
 

ttystikk

Well-Known Member
Hello, first post here...

I jsut skimmed over this thread and found a lot of great info that has been bookmarked and copy pasted to sticky notes.

I crafted some LED panels n past around 2012, but life came and never really got to use them. I'm using them now a tent and they work well. Top bin reds/warmwhite/royal b/deepred


Quick question... what would I get n VEG results w/ 2x CXB3070s AD @ 1.4mA n a 3' x 2' tent? Is it recommended to veg w/ these?
-If not what is a great option for vegging?


Already understand the flower amazing well :>>

Cheers thanks for ur time
As long as you choose a reasonable color temp, it should do very well in veg. Anything from 3500K to 6000K.
 

ttystikk

Well-Known Member
Okay, great!
What BINs have people been vegging w/ the cobs?
You know, this is a great question. One would ordinarily say top bin is best, and in the LONG term that's true, but I see some very experienced guys here choosing chips one or two bins down from the top bin, doing builds that cost much less than using the premier bin.

For veg, there's a lot of flexibility. You don't need ultimate brightness or efficiency.
 

Symbolic

Member
Ye I can see that..

https://www.fasttech.com/products/2250000
c4000k.png
its the lowest bin.. but its only 10$. veg tent is 3' x 3'. Could I get a good veg w/ 2-4 plants under 4 CXA2530 at 600mA.
That would put me around 86 watts ... or do u think i could get away w/ 2?

3'x3' tent...

thx n advance

@edit also! THIS COB is n the 80 CRI .. should I get a 4000k n the 70 CRI for more blue?
 

ttystikk

Well-Known Member
Ye I can see that..

https://www.fasttech.com/products/2250000
View attachment 3618644
its the lowest bin.. but its only 10$. veg tent is 3' x 3'. Could I get a good veg w/ 2-4 plants under 4 CXA2530 at 600mA.
That would put me around 86 watts ... or do u think i could get away w/ 2?

3'x3' tent...

thx n advance

@edit also! THIS COB is n the 80 CRI .. should I get a 4000k n the 70 CRI for more blue?
These questions are beyond my level of understanding. I'd rather say I don't know than make guesses that cost you money.
 

littlejacob

Well-Known Member
Ye I can see that..

https://www.fasttech.com/products/2250000
View attachment 3618644
its the lowest bin.. but its only 10$. veg tent is 3' x 3'. Could I get a good veg w/ 2-4 plants under 4 CXA2530 at 600mA.
That would put me around 86 watts ... or do u think i could get away w/ 2?

3'x3' tent...

thx n advance

@edit also! THIS COB is n the 80 CRI .. should I get a 4000k n the 70 CRI for more blue?
Bonjour
80cri is ok for 4000ºk!
But for a 3x3 I would go with an hlg-120-700 ...150w is what you need!
I will do the same for my 3.5x3.5x4.5 vegg tent with 9 cxa2530 (but from kb or cutter they have better bin!) On an hlg-185-700b or 11 on a 500b!
A 3x3 is 9sq/ft...9x20=180...so you need mini 150/200w no less!
CU
I
 

HammerMassage

New Member
Hi,

I'm about to buy the first few things (led & driver) I need to construct 2 Cree CXB 3590 (36v, 1.4 A) lights to cover two separate secret bloom spaces I've hidden into the house (out of necessity). Could somebody please have a look over what I am buying is correct for my needs?

Each 50w-powered cob will cover 2 different 1.2*1.1 ft grow areas (all that's doable for the foreseeable future :( ). SupraSPL mentions somewhere they use 35w /sqft, so my (1.21ft*1.1ft)/50w = 37w / sqft seems to be about right which comes to ~ 17 par w / sqft.

I plan to get 2 * Cree CXB3590 3000K 80 cri
(here: http://eu.mouser.com/search/ProductDetail.aspx?R=0virtualkey0virtualkeyCXB3590-0000-000N0HCB30G)

and I plan to drive each one with one of these:
Type: 50W LED Driver
Power: 50W
Input voltage: AC95-240V
Out voltage: DC 25-38V
Output current: DC1500mA

These come from a seller on ebay (that SurpaLED had mentioned somewhere):
http://www.ebay.com/itm/10W20W30W50W100W-Watt-High-Power-Waterproof-LED-Power-Driver-Supply-AC95V-240V-/151931593081?

CPU heatsinks and drivers for those I think I can get from work before rushing off to buy.

I typically top plants to get more cola but have found it difficult to get any decent penetration beyond the first few cm using a Tao Tronics GL-05 in a previous space.

What distance should I be placing my new COBs from the canopy?

Should I be using more watts / closer to get better penetration?


Also, very thankful of the great efforts and openness people have about sharing here. Truly great to see!
 

HammerMassage

New Member
Bonjour
A bit low for cxb3590 @1400mA...@1050mA max I would say!...700mA would be the best!
CU
Thank you! I done a little remodelling to make it higher (closer to 5.5 ft tall now), so now it's 1.1 ft * 1.2ft * 5ft.

I figure I should go with the 36v @ 1400mA = 50w for this. Could somebody confirm the driver will work with the cxb 3590 please?

driver: http://www.ebay.com/itm/10W20W30W50...Power-Driver-Supply-AC95V-240V-/151931593081?

Cree CXB3590 3000K 80 cri: http://eu.mouser.com/search/ProductDetail.aspx?R=0virtualkey0virtualkeyCXB3590-0000-000N0HCB30G
 

littlejacob

Well-Known Member
Thank you! I done a little remodelling to make it higher (closer to 5.5 ft tall now), so now it's 1.1 ft * 1.2ft * 5ft.

I figure I should go with the 36v @ 1400mA = 50w for this. Could somebody confirm the driver will work with the cxb 3590 please?

driver: http://www.ebay.com/itm/10W20W30W50...Power-Driver-Supply-AC95V-240V-/151931593081?

Cree CXB3590 3000K 80 cri: http://eu.mouser.com/search/ProductDetail.aspx?R=0virtualkey0virtualkeyCXB3590-0000-000N0HCB30G
Bonjour
Sorry I was very busy this days...
The 50w driver is ok for 1 cxb3590...so it is expensive if you need 4 of them...better buy an hlg-185-1400b and a 3500ºk 36V CD cob from www.cutter.au with CUTANDROLL code!
CU
 

MilkyP

Member
Are cobs the future now SupraSPL? I would like to see more bongs. Might finally have some money to put towards a project I was thinking about for a long time. But if your using cobs now perhaps I should just go for them :D
I'd love to give it a go myself, just have a nice smoke and follow the tut
 

RhoBotic

Member
Hello everyone!

I've been checking this forum and trawling the internet for resources for a while and am finally ready to build myself a light.
Many thanks to everyone who has provided experimental data and design resources.

I don't know if it's been mentioned but for anyone looking for tip top deep reds to supplement, led-tech in germany have (or at least claim) to have a preproduction batch of osrams next generation GH CSSPM1.24 horticultural 660nm ssl120 for those interested, which boasts a min 400mw @ 350ma drive current. The voltage range on their website looks suspcious, quoted at 1.6v - 2.3v. They differentiate between min and max values, so really the min voltage should match up to the min current that they state, but I doubt this as that would give an efficiency of just over 57%. Here's the link to the release note: http://www.osram.com.cn/media/resource/HIRES/546291/538626/15-gb.pdf From what I understand though osrams red chips do perform better at lower drive currents.

So my build is for a micro cab that will be 45cm x 60cm x 1m (Depth-Width-Height) and I very luckily came across 4 62v (0.3-1A) 50w philips xitanium DALI drivers on ebay for cheap. I'm going for a super efficient set up, with full control of spectrum and high efficiency, so I can make it stealthy quiet on the extraction side. I'll be using a 6" phresh hyper fan on low @ 8w for the extraction :)

So far I'll be using

2 x cree cxb3590 @ 13w - 35w approx. each (max 70w total)
(10 x osram Oslon SSL 80 LHCP7P-2T3T @645nm) maybe
24 x osram GH CSSPM1.24 SSL 120 (Horticulture) @660 nm (approx 17w - 40w)
6 x osram CS8PM1.24-3S4S-1 @730nm
as of yet unknown quantity of either cree XTE or XP-E2 royal blue
1 or maybe 2 x 11w arcadia D3 7% UVB lamp

I might need more drives to control it all how I'd like, but I also plan to integrate this into a fully automated system, with data logging of all sensory info, communicating over wifi or GSM, with a control application running on a raspberry PI.

So I'm really posting to get opinions about colour temp. From what I understand 3500k has been hailed as the optimal colour temp for a single led solution, however my build is going to use the cree cob as a base and then supplement both red and blue. In my opinion they all need extra deep re 660nm which is unavoidably inefficient. Now from what I understand a COB led is basically something like an XTE blue array without the lenses with a phosphour LES, which in my mind makes me think that every photon is penalised by the phosphour, including the blue spectrum.

The drop in efficiency compared to the distribution of blue to red between 4000k,3500k and 3000k makes me think that using the 3000k CB bin and supplimenting with blue LEDS, which are much more efficient than the reds is the way forward. If I run the royal blues at 100ma in flowering the efficiency gain will cancel out or better the efficiency gain of the CXB efficiency gain from using a higher bin in a higher colour temp. At the same time I gain the benefit of the fact that the CXB 3000k does a really good job at providing red in the 620 - 630 nm, as well as green and yellow and having a string of royal blue, I can dim the COBs and crank up the blues for veg.

I'm yet to do proper calculations, which are part science part voodoo anyway, but I thought I'd ask the opinions and knowledge of those with more experience first. I'd really appreciate any input.
 
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