Custom COBCRETE

Does Discrete leds on a COB footprint make any sense

  • Yes for non COB Colours

    Votes: 10 50.0%

  • Maybe

    Votes: 9 45.0%

  • No

    Votes: 2 10.0%
  • Total voters
    20
welight

welight

Well-Known Member
Stephenj37826 said:
It makes sense. The question to me is cost value. Domed leds of course have a different radiation pattern. If these have a tighter beam angle similar to using an optic with cob one could justify the extra cost involved.
Click to expand...
my initial thought is XP(3535) footprint as it has the widest ecosystem of leds on the planet, however a 2nd variant would double the led count and move to XQ(1.6mm sq) this comes in the HI or flat top platform so would obstensibily look like a traditional COB when assembled. Will know more on final beam after we build a few and test
Cheers
Mark
 
welight

welight

Well-Known Member
CobKits said:
to be honest the marketability of such a product kind of depends on whether the trend goes toward cobs or boards

i will say there is a gap in your product line between the 3-up star boards and the 15 linear strips and then solskin where this could fit

Q for you: what does the efficiency of an XPE vs a 561C look like on a cost basis. assuming in most of our applications we are NOT filling up the pcb with diodes and have room to work so lumen density of the emitter is off the criteria list

for example without doing the math i see that a chillled uses 561C for white but then the smaller xpe-style diodes for colors. i assume for white light the larger 561C are cheaper at a given efficiency?
Click to expand...
a picture paints a k words

No doubt in a small form factor, XP can deliver a lot of light relative to Mid Power, which in exotic colours or blends I think COBCRETE might offer a solution
Cheers
Mark
 
welight

welight

Well-Known Member
Greengenes707 said:
Yes, makes total sense. They give tunability and the can get efficacy really up at lower currents. But the price/cost compared to other platforms like COB's is not exactly there. Almost 50% more cost for the same efficacy sometimes. So in the raw efficacy : price race, it's not a great choice. But if spectral signals/specialization is needed, it's very convenient to just drop it into a rig ready for COB's.
We have been making something similar for a little bit and has been working real well and made some spectrum chasing growers very happy. 36 chips 3535, in 36v or 50v configurations. Thermally perform very well, but we use a copper version. Blending is good and cob lens options all work great.
They come out between 1.9-2.0µmols/w depending on Tc ability of the build for ~100w of dissipation(same as a vero b and c for 20-25$). But creep to ~2.5µmols/w in the 40-50w range, and are as good of efficacy as anything pretty much, but cost again.

View attachment 4010736 View attachment 4010699 View attachment 4010703 View attachment 4010702


EDIT:
@welight Have you got your hands on some of the XD16 yet? I haven't. The new XD16 chips could/should make these designs easier and maybe cheaper to get efficiency up.
Click to expand...
Hi GG
Nice boards, so these are Sinkpads and we will be using our own TPAD DTP Copper Boards, so basically same idea, sounds very promising based on your results
I have 300 XD16 4000k samples requested loaded into Durham, I keep chasing and feedback is they are about 4 weeks behind where they expected to be, so hope to get mine late Sept as of today.
Cheers
Mark
 
W

waveman

Well-Known Member
CobKits said:
tunable to an extent as well

osram makes the SSLs in 80, 120, and 150 degree flavors
Click to expand...
Can someone help me with a plan to cover 32'x32' flowering room. I have a limiting factor of about 20,000Watts dedicated to flowering lights. Using 12-50W COB lights pulling 420W per light as Growmau5 suggests I'll have 1.8 sqft per COB which is far from the desired 1 sqft per COB. Can someone suggest another route that could increase the number of COBs so I can get the 1 COB/sqft density but not exceed my 20,000Watts? I'm also not trying to spend $50k on flowering lights which seems to be the case if I went with the kit on Cutter.
 
  • Like
Reactions: G84
CobKits

CobKits

Well-Known Member
waveman said:
Can someone help me with a plan to cover 32'x32' flowering room.
Click to expand...
20000W would be short on a 32x32 space, thats under 20W per square foot total input wattage. it would have good gram/watt but on the low end of gram/sq ft. (aka overall yield)

theres no reason to need 1 cob per sq ft. you could do 70W per cob and get >2 sq ft/cob with fantastic results. youd still be looking at 500 cobs/heatsinks and about 35000W

rough budget if you did a build of that size (with a healthy discount from the supplier) $22-$25K

if you really want to work with around 20KW youre gonna need to spend a lot on cobs, 1024 cobs underdriven at 37W, one per square foot, closer to $35K depending on choice of heatsink
 
W

waveman

Well-Known Member
CobKits said:
20000W would be short on a 32x32 space, thats under 20W per square foot total input wattage. it would have good gram/watt but on the low end of gram/sq ft. (aka overall yield)

theres no reason to need 1 cob per sq ft. you could do 70W per cob and get >2 sq ft/cob with fantastic results. youd still be looking at 500 cobs/heatsinks and about 35000W

rough budget if you did a build of that size (with a healthy discount from the supplier) $22-$25K

if you really want to work with around 20KW youre gonna need to spend a lot on cobs, 1024 cobs underdriven at 37W, one per square foot, closer to $35K depending on choice of heatsink
Click to expand...
I made one change to the flower room making it 24x32 (768 sqft). Unfortunately my wattage is transformer limited to about 20kW for the flowering room. How close can CXB3590 get to the plants at 37W vs 70W? I know with my old set up using air cooled 600W lamps I could get 6-8" from the plants which seems to produce well at around an 3/4 ounce/sqft. If I went with the underdriven COBs at 37W and used 1024 of them isn't that still over 35000W? I don't fully understand the wattage required for the COBs...
 
CobKits

CobKits

Well-Known Member
waveman said:
How close can CXB3590 get to the plants at 37W vs 70W?
Click to expand...
i wouldnt even be considering that chip for your application, chip cost is your #1 expense and you can cut it in half by not using 2015 technology

in your case you dont really want them super close to your plants, you want uniform light

rule of thumb for cob arrays: distance to plants=spacing between cobs (at least)
 
W

waveman

Well-Known Member
CobKits said:
i wouldnt even be considering that chip for your application, chip cost is your #1 expense and you can cut it in half by not using 2015 technology

in your case you dont really want them super close to your plants, you want uniform light

rule of thumb for cob arrays: distance to plants=spacing between cobs (at least)
Click to expand...
Which chip would you be looking at? What would my load on the transformer be if 1024 COBs were driven at 37W?
 
CobKits

CobKits

Well-Known Member
waveman said:
Which chip would you be looking at?
Click to expand...
luminus cxm22, vero 29, and citizen gen6 are currently at the top of the efficacy/cost curve

waveman said:
What would my load on the transformer be if 1024 COBs were driven at 37W?
Click to expand...
1024x 37W= 37.8 KW
37.8 kW / 93% driver efficiency = 40.6KW

sounds like your power is not adequate for your space and no amount of cob magic is gonna fix that
 
W

waveman

Well-Known Member
Yes you are correct. I want to find these things out now while still designing and I sure appreciate your help. I will need to scale down the size of my flowering room as it seems my UT 50 STD 120 transformer is my limiting factor. I would not have guessed this to be the case.

The trimming room will be more spacious and the whole build will cost me less up front. Now that I know the power is the limiting factor COBs are still the right move as they are so much more efficient than the HPS correct?

In my previous grow I had one 650 CFM fan per 2 600W HPS lamps in Super Sun II hoods. My goal with this build was to build a room that was as efficient as possible to keep the electric bill in check. Now it has morphed into keeping the grow with in my transformers capacity...
 
wietefras

wietefras

Well-Known Member
Price difference between a CXB3590 and Citizen 1818 isn't that big anymore though. Something like $27 vs $21,5. Being able to use constant current drivers with easy serial wiring also has it's merits.
 
W

waveman

Well-Known Member
wietefras said:
Price difference between a CXB3590 and Citizen 1818 isn't that big anymore though. Something like $27 vs $21,5. Being able to use constant current drivers with easy serial wiring also has it's merits.
Click to expand...
If these lights will only be used as flowering lights which type or types would be the standard? I see color ranges from 2800K to 6500K
 
wietefras

wietefras

Well-Known Member
waveman said:
If these lights will only be used as flowering lights which type or types would be the standard? I see color ranges from 2800K to 6500K
Click to expand...
Usually I think 3000K, but you'll also see some people use 2700K or 3500K. I'm with 3000K 80CRI myself.
 
dandyrandy

dandyrandy

Well-Known Member
I've been happier with my cobs than boards. I get more material if you will. I have 4 I need to put on fleabay. I would be interested.
 
CobKits

CobKits

Well-Known Member
wietefras said:
Price difference between a CXB3590 and Citizen 1818 isn't that big anymore though. Something like $27 vs $21,5.
Click to expand...
1818 out performs it as does the $17 luminus cxm22

not sure where cxbs are $27
$30+international shipping at cutter
$28+paypal fees+international shipping from kingbrite
$38 domestically at rapidled

$17 vs $32-$38 is pretty significant
 
welight

welight

Well-Known Member
CobKits said:
1818 out performs it as does the $17 luminus cxm22

not sure where cxbs are $27
$30+international shipping at cutter
$28+paypal fees+international shipping from kingbrite
$38 domestically at rapidled

$17 vs $32-$38 is pretty significant
Click to expand...
We can do $27 in volume no problem
 
CobKits

CobKits

Well-Known Member
just trying to be apples to apples by sticking to unit price, assuming all parts get discounted (similarly) in bulk

is the new product announcement imminent?you mentioned sept newsletter? (no fault on you if cree delays of course :), just genuinely curious)
 
Last edited:
PilouPilou

PilouPilou

Well-Known Member
Hi mark! no more CXB 36V in stock?
They are available with the CXB359-LHA8-36VKIT but I don't understand why we can choose only 4 Angelina reflectors in the options... there are 8 CXB in the kit?
 
Last edited:
You must log in or register to reply here.
Top