LED COB bar project

dandyrandy

dandyrandy

Well-Known Member
I run 9 vero 29's with a variable driver on each. Meanwell lpf-90d-42. Usually $45 each. 1 bar runs 300w approx. 3 per bar. Vero 29 and pc heatsink around $45 total x 3. Then I used angle aluminum from Blows. Yeah Blows. Homey depot was farther away. 12v switching supply $3 from fleabay. I figure $300 per bar parts only. I have 3 bars in a 40x46 area. You can run efficient or blast it at 900 w.
 
Rahz

Rahz

Well-Known Member
salmonetin said:
...another answer in the wind...

...Wilson... i told you... you win this time...time to infusion and back to the cavern...


saludos
Click to expand...
Sorry I didn't respond, the answer was in Supra's first reply, just figured it would stick out.

Dissipation watts. Im lazy. V29 at 1A would be very close to effeciency of CXB3070 at 1.4 and one of those per foot is no joke. More light than the generic at 60 watts.
 
salmonetin

salmonetin

Well-Known Member
...thanks Rahz...

...some people when talking about to W / sq-ft or W / m2... refers to Dissipation W... ...other refers to PAR W...

...but from my pov when we talking about W / sq-ft or W / m2 ...we usually refer to PAR W....not to Dissipation W...

...but maybe im wrong offcourse... ...its only my pov...

...for this cause when i see people recommend xx W / sq-ft or W / m2 ...I ask to my self ...he refer to Dissipation W or PAR W?? ...50 W / sq-ft or 50 W / m2 Dissipation W ...are diferent to 50 W / sq-ft or 50 W / m2 PAR W...

...from churchhaze...

...A good rule of thumb is to use 12 W / sq-ft PAR for 2 - 3 foot plants, 14 – 18 W / sq-ft PAR for taller.

...sorry @SupraSPL... can you refresh me with your recomendations about W / sq-ft and W / m2 (w/m2 are a bit direferent values... not?) and remark if are Dissipation W or PAR W... please...

...thanks in advance...

Saludos
 
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SupraSPL

SupraSPL

Well-Known Member
@salmonetin I run at least 15 PAR W/ft² in the flower tents. That is for tall ladies with underbrush pruned out, 3-5 feet tall including the bucket. That is 3000K, 25 dissipation W per COB, and many heatsinks armada style, so good spread in the canopy.


bmdiyh said:
OK, if I decide to go for example for the above ( 4 V29s @ 1.4A), which will add up to 200 W per bar. How hot are we talking? What cooling do I have to get for them? What temperature could they reach, and at what temperature should I run them? How many fans would I need, how powerful? Or could I run passive cooling for this kind of setup? The heatsink(s) - are there available kind of what i showed in the picture above or will I have to change the desing concept... I want them to be as harmless as possible to the plants at, let's say a foot of distance (comments on the distance? ).

One more thing! You mention color temperature of 4000K. I am going to use these light only for flowering do you think this is the best CT. What is 2700-3000-3500K range about? Isn't it better for flowering? Or a mix?

Thank you all again for the "lessons" ;))
Click to expand...
When I size heatsinks, I aim to run them cool (Tj 40-60C) to minimize temp droop. Veros stand up to heat very well so running them at 50W ea, you might get ~2-3% temp droop. If you want passive cooling, you would have a monster on your hands, HeatsinkUSA 8.46"X36" heatsink would do a good job. If you want active cooling you could use HeatsinkUSA 3.5"X36" with a single 80mm fan. A third option, you could use 4 of these. The picture in your first post shows the COBs on the very edge of the heatsink. That would result in a higher Tj for those COBs. I am not sure how much that would affect temp droop in practice but when it comes down to it I believe that even light spread is much more important than even heat spread in the heatsink.

Also, if you have a 3 foot tent you might want some air space on the sides of the heatsinks so 30" might work well but if you are working with a 4' tent you could use 40" heatsinks. The separate CPU cooler option would address that but results in more wiring and more fans.

As far as distance to canopy, with 50W Veros I would highly recommend lenses or reflectors even if you have a mylar lined tent. The angle of the lens/reflector you choose would affect the optimal distance to canopy. The 50mm 90 degree lenses are a good width for CXB3590s and Vero 29s.

I mentioned 4000K kind of arbitrarily. You could use 3K 3.5K or 4K. I have always used 3K but currently testing 3.5K and 4K. It may also depend on the type of ladies you run. If you have a stocky bushy indica-dom you might do better with 3000K and if you have a stretchy sativa-dom maybe 4K would be helpful.
 
salmonetin

salmonetin

Well-Known Member
...thanks Supra...

...and pardon to bmdiyh for hijack a bit your thread with mine dudes... and thanks to all

...Wilson... time to infusion and back to the cavern ... time to read...

saludos
 
bmdiyh

bmdiyh

Well-Known Member
OK! I have taken a look at some of the commercial lights out there. And I looks like they run the COBs at higher wattage. Not at a low one how I wanted, so... What if I drive for example one Vero 29 with one HLG-120H-42A. First is it possible or is it going to fry/blow up? If possible how efficient would it be? Would I have trouble with heat? Generally, I think that having less more powerful chips would be cheaper. They add up to about 12 pieces for my flower space. What do you think?? If this combination does not work, but you get my drift, could you give me some example of what I could do?
 
bmdiyh

bmdiyh

Well-Known Member
Great! I was wondering if there was something like this. Although, from the twelve columns in the spreadsheet I only get the first and the last one... I could start pondering on the abbreviations but I'll surely get lost. I am sorry to be such a newbe but I don't get much of those stuff. Can somebody point me in the direction where they are explained.

From the little I understand from the spreasheets I see that the more the amps are the less the efficiency, ergo higher the temperature, and "bigger" the cooling. Is this right?
 
robincnn

robincnn

Well-Known Member
Supra's Spreadsheets 101
Amps= Current, Factor dont know, Lm25C is lumen output at 25 degree C, Lm50C lumen at 50 degree temp, VF25/50- forward voltage at 25 degree or 50 degree
50c DissW means total watts of consumption.
then 50 degree c lumen/watt, then 50c% is efficiency at 50 degree temperature, lastly $/par watt
Yes the higher you drive them the more hot, inefficient they get.
Go with one of Supra's recommendations. Good luck.
 
C

churchhaze

Well-Known Member
bmdiyh said:
From the little I understand from the spreasheets I see that the more the amps are the less the efficiency, ergo higher the temperature, and "bigger" the cooling. Is this right?
Click to expand...
Exactly.. Higher efficiency means you can use less watts dissipation to get the same watts output of radiation between 400nm-700nm. ("Official" PAR range). With a 100% efficient lamp, you technically wouldn't need heat sinks at all. 100% of the dissipated power would be radiated from the light emitting surface, thus no need for heat sink.
 
salmonetin

salmonetin

Well-Known Member
robincnn said:
Supra's Spreadsheets 101
Amps= Current, Factor dont know, Lm25C is lumen output at 25 degree C, Lm50C lumen at 50 degree temp, VF25/50- forward voltage at 25 degree or 50 degree
50c DissW means total watts of consumption.
then 50 degree c lumen/watt, then 50c% is efficiency at 50 degree temperature, lastly $/par watt
Yes the higher you drive them the more hot, inefficient they get.
Go with one of Supra's recommendations. Good luck.
Click to expand...
https://www.rollitup.org/t/cob-efficiency-spreadsheets.865238/page-6#post-11694581 ...;)...

saludos
 
alesh

alesh

Well-Known Member
bmdiyh said:
OK! I have taken a look at some of the commercial lights out there. And I looks like they run the COBs at higher wattage. Not at a low one how I wanted, so... What if I drive for example one Vero 29 with one HLG-120H-42A. First is it possible or is it going to fry/blow up? If possible how efficient would it be? Would I have trouble with heat? Generally, I think that having less more powerful chips would be cheaper. They add up to about 12 pieces for my flower space. What do you think?? If this combination does not work, but you get my drift, could you give me some example of what I could do?
Click to expand...
Well, you can but IMHO it doesn't make much sense.
It's not really cheaper than multi-COB solutions. Runs inefficiently (<36%; hardly better than a HPS). Loses the advantage of better distribution of light. The only advantage I can see is that one COB is easier to mount than multiple ones.
Here's how it compares against some other combos (some prices might be a little outdated but you get the point).
cob_comparison_25_6.jpg
 
bmdiyh

bmdiyh

Well-Known Member
So it doesn't matter how many watts consumes the whole setup! The thing that matters is the PAR W//ft². From what I read I'll nee at least 15 PAR W//ft² for "3-5 feet tall including the bucket". For example if I run a 30 Dissipation W/ft² setup at 50% efficiency I will get 15 PAR W//ft² and the other 15 W are turned into heat. Is this correct? With more efficient COBs I will get more PAR W//ft² for every Dissipation W/ft², which automatically lower the need of a lot of watts, and decreases the cooling needs of the setup. Am I right in thinking that? Did I get it? Is this the whole point of everything?
 
alesh

alesh

Well-Known Member
bmdiyh said:
So it doesn't matter how many watts consumes the whole setup! The thing that matters is the PAR W//ft². From what I read I'll nee at least 15 PAR W//ft² for "3-5 feet tall including the bucket". For example if I run a 30 Dissipation W/ft² setup at 50% efficiency I will get 15 PAR W//ft² and the other 15 W are turned into heat. Is this correct? With more efficient COBs I will get more PAR W//ft² for every Dissipation W/ft², which automatically lower the need of a lot of watts, and decreases the cooling needs of the setup. Am I right in thinking that? Did I get it? Is this the whole point of everything?
Click to expand...
Yes, spot on. It might be even better to compare photon output (µmol/s) than energy output (W) but this is good enough.
 
bmdiyh

bmdiyh

Well-Known Member
From what I get from the spreadsheet I'll need around 480 PAR W for the 32 ft² I have. And I came up with two a around 50% efficient setups:

20 x [email protected] (49W) (51.67%) = 504.82 PAR W (15.77 PAR W/ft²) (977.01 Dissp W)

12 x [email protected] (80W) (50.97%) = 490.04 PAR W (15.31 PAR W/ft²) (961.43 Dissp W)

Please correct me if I am wrong! If these can work can you tell me with what drivers? Or is the voltage too high? I don't know, please tell me what you think and if possible how can I drive those two setups.
 
alesh

alesh

Well-Known Member
bmdiyh said:
From what I get from the spreadsheet I'll need around 480 PAR W for the 32 ft² I have. And I came up with two a around 50% efficient setups:

20 x [email protected] (49W) (51.67%) = 504.82 PAR W (15.77 PAR W/ft²) (977.01 Dissp W)

12 x [email protected] (80W) (50.97%) = 490.04 PAR W (15.31 PAR W/ft²) (961.43 Dissp W)

Please correct me if I am wrong! If these can work can you tell me with what drivers? Or is the voltage too high? I don't know, please tell me what you think and if possible how can I drive those two setups.
Click to expand...
CXA3590 doesn't seem likely to be 50% efficient @1.05A. According to @SupraSPL the CB bin is 43.28% efficient @1.05A.

For driving 20x CXB3590 @700mA you can use 5x HLG-185H-C700.
 
bmdiyh

bmdiyh

Well-Known Member
SupraSPL said:
For now the CXA DB beats the CXB CB and because of the lower price you can afford to drive them softer. But CXA may be limited in supply and the CXB3590 5000K DB and DD may become available and maybe prices keep coming down if the USD stays strong.

View attachment 3441764


View attachment 3441772
Click to expand...
I did my calculations according to this post.

First attachment is:


Anyway I'd like to run my setup at 50% efficiency if possible so I don't get a lot of heat, and the whole thing would not consume a lot of electricity compared with the PAR W output.
 
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