Cree cob question ..... Is 100w / ft overkill ?

vitamin_green_inc said:

Think he's saying we don't really go by watts per sq foot, but that's just him being like a grammar-nazi. Watts per sq foot as long as the audience knows what model cob and what the OP is looking for is an okay tool to make it easier to digest in people's minds. So you keep doing you OP and don't worry

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i really just meant ..... Will my plants run around with their hair on fire ???????


i think my hps ballast is on its last leg ........ fresh bulb and its still missing some kick

kinda want to make smaller bars with maybe 2 - 3 cobs on it ... would be easier to position them i think

What we need is to get a group of guys together that know LED tech and plant photosynthesis. That group could put together a sticky for this section that could act as a beginners guide to understanding and comparing terms for both. It sounds like a lot of work to put something like that together so that novices could get a grip on this info to make lighting decisions. I think such a sticky would make it easier for novices and the people trying to help them.

captainmorgan said:

What we need is to get a group of guys together that know LED tech and plant photosynthesis. That group could put together a sticky for this section that could act as a beginners guide to understanding and comparing terms for both. It sounds like a lot of work to put something like that together so that novices could get a grip on this info to make lighting decisions. I think such a sticky would make it easier for novices and the people trying to help them.

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I believe I'm currently one of the novices you're referring to here.

It's been pretty difficult just to get a handle on the basics, such as a parts list for a typical COB build, for instance; even simpler than specific part numbers, just knowing the parts exist and what's needed for a complete kit.

Next, the charts for the different chips are only helpful if given context.

Charts for drivers, same thing.

Wiring.

Miscellaneous bits.

At this point, I've made the decision that any COB project I build needs to be fully compatible with my electrical system, which means grounding and proper plugs. Wiring diagrams. Haven't seen them.

I'm also not very well versed in electronics, and I have little experience with electrical DIY, house wiring for my grow being the exception. This likely makes me a better test subject!

captainmorgan said:

I think you need to balance what people can easily understand with the technical side. You can't expect everyone to take a crash course in LED tech and plant photosynthesis just to buy a light for a small grow. I'm sure there are plenty of people that hear all the tech speak and think it's just too complicated and buy HPS,whether it fits their needs or not. If your a enthusiast or going to make a large investment you should get educated and learn all the right terms but it's not for everyone.

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....ok maybe i need to balance what people can easily understand with the technical side...
...but its not so hard understand the basic technical side...
...and..............ok ok... i dont talk more here about par watts or dissipated watts and w / ft2 or W / m2...

...understand the par wats or disipated wat its not too dificult to learn... for my pov... but heyyyy ... its only my pov...

...off course i dont expect everyone to take a crash course in LED tech and plant photosynthesis just to buy a light for a small grow...and... if the people think it's just too complicated for they and buy HPS, whether it fits their needs or not... its they prerrogative too.. nobody force to nobody to buy nothing... if you know the basics how to on the diy led working... you are best prepared to asume better decisions buying things... my 2 cents..

...and now i shout my mouth and back to my cavern... all thread for you guys...

saludos

salmonetin said:

....ok maybe i need to balance what people can easily understand with the technical side...
...but its not so hard understand the basic technical side...
...and..............ok ok... i dont talk more here about par watts or dissipated watts and w / ft2 or W / m2...

...understand the par wats or disipated wat its not too dificult to learn... for my pov... but heyyyy ... its only my pov...

...off course i dont expect everyone to take a crash course in LED tech and plant photosynthesis just to buy a light for a small grow...and... if the people think it's just too complicated for they and buy HPS, whether it fits their needs or not... its they prerrogative too.. nobody force to you to buy nothing... if you know the basics how to on the diy led working... you are best prepared to asume better decisions buying things... my 2 cents..

...and now i shout my mouth and back to my cavern... all thread for you guys...

saludos

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youre all good brother .... TBH i would of explained in better detail .... had i a better understanding .... at this point all i know ..... run them in series at a lower wattage then they are rated .... have some way to cool them .... thats about it .... Really just want the best light i can fill my room with ..... No more damn shadows

I've made it part of the way through the DIY driver sticky ....... stand back I watched this on youtube once i'm a pro I gotta lay off sativa's

Ok lets say i just took the plunge got the led's and wired them all in .... im going to want to use the same length of wire between them ?? and after i get them hooked up could i ohm the series out to judge what driver i would need ??

tekdc911 said:

Basically the question is what the title states .... Would a 100w 3000k cob per square foot be detrimental to my plants or am i thinking too much into it ?

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I say go for it if you can manage the grow area temps. MORE POWER!!!!

ttystikk said:

I believe I'm currently one of the novices you're referring to here.

It's been pretty difficult just to get a handle on the basics, such as a parts list for a typical COB build, for instance; even simpler than specific part numbers, just knowing the parts exist and what's needed for a complete kit.

Next, the charts for the different chips are only helpful if given context.

Charts for drivers, same thing.

Wiring.

Miscellaneous bits.

At this point, I've made the decision that any COB project I build needs to be fully compatible with my electrical system, which means grounding and proper plugs. Wiring diagrams. Haven't seen them.

I'm also not very well versed in electronics, and I have little experience with electrical DIY, house wiring for my grow being the exception. This likely makes me a better test subject!

Click to expand...

There's all that info here but it's spread around but I think it would be tough to put into a sticky because the tech is advancing very fast. Supra has done a lot of great work putting threads together on the main parts,COBs,Power,Heatsinks,Reflectors and more.

salmonetin said:

....ok maybe i need to balance what people can easily understand with the technical side...
...but its not so hard understand the basic technical side...
...and..............ok ok... i dont talk more here about par watts or dissipated watts and w / ft2 or W / m2...

...understand the par wats or disipated wat its not too dificult to learn... for my pov... but heyyyy ... its only my pov...

...off course i dont expect everyone to take a crash course in LED tech and plant photosynthesis just to buy a light for a small grow...and... if the people think it's just too complicated for they and buy HPS, whether it fits their needs or not... its they prerrogative too.. nobody force to you to buy nothing... if you know the basics how to on the diy led working... you are best prepared to asume better decisions buying things... my 2 cents..

...and now i shout my mouth and back to my cavern... all thread for you guys...

saludos

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I'm not trying to be critical and love the deep stuff. I just wish it was easier for beginners to get a grasp on this stuff. As someone that tries to help out now and then it would make it easier. It gets tiring having to explain the same things over and over,especially with fending off trolls and morons. A sticky for the beginner would help and could also have links to the more technical stuff.

puffenuff said:

I say go for it if you can manage the grow area temps. MORE POWER!!!!

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Im running a 400w hps and around 240w of led .... i stay mid 70's

It is hard to sort through it all ..... i really just dont want to buy some dinosaur tech from 10 years ago if i can avoid it ....

Check out some YouTube videos on basic electronic wire knowledge and the difference between watts, amps,volts, and ohms. A basic understanding will do you wonders when trying to run wires. If soldering is too much the Vero 29 has a plug in wire piece making it solder free. I herd that there is a Cree cob holder thar could make it solder free also, but I am not positive on that one.

I use the Ideal solderless holders for my Cree CXAs.

I actually talked with one of the guys that developed and tested that CXA holder quite by accident,he now works in a cannabis related field and we were talking growing and LEDs,how's that for coincidence.

captainmorgan said:

i'm not trying to be critical and love the deep stuff. I just wish it was easier for beginners to get a grasp on this stuff. As someone that tries to help out now and then it would make it easier. It gets tiring having to explain the same things over and over,especially with fending off trolls and morons. A sticky for the beginner would help and could also have links to the more technical stuff.

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...captain... amen... im your fan too...

saludos

I have DD bin 6500k that I haven't assemble yet and they are CXB 3590's. Some say I'm a rookie at this but I've been into building computers for 20 years and I learned how to make COB led's in 6 months. I've been wanting to make led grow panels since 2008 but didn't get around to it but I'm glad I waited. Oh yeah I buy all my Cree cob's from kingbrite they have the best prices and the top bin http://kingbriteled.en.alibaba.com/

Yeah, and I forgot to point out, and it probably needs to be added to a thread about LeD basics because noobs will want to go China LED because of price and regardless of what you tell them...I think if you are running "blurple" you need to be sitting at least 35w per sq foot, and if it's 3w diodes, probably more like 45-50w per sq foot, and so then they will begin to realize that even though that can be more efficient than HPS, barely and you would have to include ALL the factors in, such as cooling costs etc. To make it better, the effiecny is THAT much better when you run Cob, because not only do you need only 1/3-1/2 of the "blurple" power to equal a yield, but that's not including the other costs such as total cooling etc.

I have run several blurple panels, and continue to do so! But I understand that when I do, I need to be hitting half of what the manufacturer recommends as far as optimal bloom area, so like a 200w will do a 4-5 sq foot area, but most of the companies will claim it can do a 3x3 and that's just not optimal and a 400w HPS would do better in such a space than just one 200w actual blurple light.

I've had a few blurple 90W UFO LEDs, and they just didn't really do shit. I knew that LED tech was growing by leaps so I bided my time...

And that time has come.

https://www.rollitup.org/t/diy-led-grow-lights-with-cree-cxa3070-cobs-and-cpu-coolers.805681/

i have a butt load of old pc's laying around .... think im gonna do this build but just 2 cob's ..... and use aluminum gutter for the enclosure ...... thank you all for the interesting convo

http://www.amazon.com/Package-5-TEC1-12706-Thermoelectric-Cooler/dp/B00KTV5AYQ

These give me some idea's

1.8ft x 5.25ft area with 4CXA3590 5000K 0.7A about 200w. I got 4 heatsinks put together as one, the size of the heatsink as one 23.77" x 13.77". I got the heatsink placed above 12" away and all the way on the left hand side of the tent. So pretty much its lighting up the entire area but mostly on the left hand side of the tent which is about 1.8ft x 2ft - (3.6ft2)

. I'm planning to add another same setup so there will be two inside the tent, one covering the left side & one covering the right side. Right now the 200w cxa3590 5000k is covering about 1.8ft x 2ft area but its inside a 1.8ft x 5.25ft tent. Does that mean I'm getting 55w/ft2 lighting up a 1.8ft x 2ft area?

The plants are looking healthy. Temps inside the tent ranges from 24-30c. Ive read that it should be at 55w/ft2 minimum.

5.4ft L x 2.4ft W x 5.4ft H. Looking at my current cree cxa setup with the current heatsink, planning to put two CXA/CXB per heatsink powering 100w each on the next build. Planning on doing 2x 400w 3000k build for flowering and planning to shove it in that 5.4ft x 2.4ft closet. Producing 64w/ft inside there.