400w CXB3070 LED build

You can run veg with the lights, but I do not. I was using a T5 for veg, but I am building a 200w CXB3590 5000k light. If you want to veg and flower, I would go with 3500k or 4000k for a happy median.

I also do not dim my lights. I have not found a need to as they plants have always done well under full power. True power draw from the wall is 442w with BOTH lights. They draw 221w each.

I run 10 plants in my area 2x5 area. I am not currently running as I am moving in a week, but new setup will be much better. I top them I think 3 times on both runs (HPS and LED). I personally do not feel plant count is a big deal. I can run 3 plants in my area and grow them larger, or run 10 smaller. You just have to veg longer w/ 3 plants. 10 plants cuts down on veg time.

As far as the pot size comparison, I did do multiple pot sizes in the same area, same amount of plants. The 5 gallon did do a bit better than 3 gallon, but I am not sure its worth the extra cost of soil in the end. I would definitely use 3gal over 2gal though. And use 5gal if you plan on growing less plants in your same area (or even 7gal). SOrry for the late response, not sure how I missed it @Humanrob .

doz said:

Mine was $325 w/ all parts although prices have come down on some things and also could have done stuff a bit differently. I think $300 is plenty doable for 200w. Considering 200w will probably equal a 400w HPS, its not a bad deal. For a quality HPS setup, it will run you $200 (400w). Now, you can say that you can get HPS setup cheaper and you can, but then you are losing quality. Go cheap on the LED and you can get the cost down too.

Id look at getting away from all that garbage blurple GUOD and build one of these. Far more efficient than anything on the market and its a fun project.

As far as smoke, tried a little early (I know, not cured, its a sin) and its hard to say. There are man more trichs packed inside than HPS. I do believe its a little stronger, to the point where you do not have to smoke as much. The actual high is about the same.

Click to expand...

How do you equate that your 200w cob light is a replacement, results wise, for a 400w HID? Nice build a good info. I'm just a little torn about my build.

I want to replace a 400w HID with a cob light. Greengenes says 5 3070's on an hlg 240-1400 but I was never clear that would replace the 400w.

Your thoughts?

Listen to green genes. If you want to absolutely match (and exceed) a 400w HPS, 5 CXBs at 50w each is very nice. You will get a better spread if you build it right as well.

giantsfan24 said:

How do you equate that your 200w cob light is a replacement, results wise, for a 400w HID? Nice build a good info. I'm just a little torn about my build.

I want to replace a 400w HID with a cob light. Greengenes says 5 3070's on an hlg 240-1400 but I was never clear that would replace the 400w.

Your thoughts?

Click to expand...

bizfactory said:

Listen to green genes. If you want to absolutely match (and exceed) a 400w HPS, 5 CXBs at 50w each is very nice. You will get a better spread if you build it right as well.

Click to expand...

CXB3070 BB's
5x49.8w=249w@51% with a QER of 4.65µmols/Rw
249 x 51%=126.99 x 4.65=590µmols PPF

400w HPS
400w@32% with a QER of 4.63
400w x 32%(brand new)= 128 x 4.63= 592µmols PPF

Greengenes707 said:

CXB3070 BB's
5x49.8w=249w@51% with a QER of 4.65µmols/Rw
249 x 51%=126.99 x 4.65=590µmols PPF

400w HPS
400w@32% with a QER of 4.63
400w x 32%(brand new)= 128 x 4.63= 592µmols PPF

Click to expand...

Man gg... Thank you!

Greengenes707 said:

CXB3070 BB's
5x49.8w=249w@51% with a QER of 4.65µmols/Rw
249 x 51%=126.99 x 4.65=590µmols PPF

400w HPS
400w@32% with a QER of 4.63
400w x 32%(brand new)= 128 x 4.63= 592µmols PPF

Click to expand...

Does the math equate to real world measurements? Reason I ask is the 400w HPS shoots lights out all around, I wonder if the plant sees them as close as the math or if COBs are much higher being directional.

Greengenes707 said:

CXB3070 BB's
5x49.8w=249w@51% with a QER of 4.65µmols/Rw
249 x 51%=126.99 x 4.65=590µmols PPF

400w HPS
400w@32% with a QER of 4.63
400w x 32%(brand new)= 128 x 4.63= 592µmols PPF

Click to expand...

Ok so it's the watts of the driver, in this case just slightly under 250, ÷ by the number of cob's is how you're coming up with 49.8w per cob?

I know I'm focusing on watts here but bear with me... Because 5 cob's is the most this driver can "fit" as far as efficientcy is concerned, (I hope I got that right) if I got a driver, hypothetically, that fit 6 cob's at the same wattage but only used 5 cobs, would the wattage still be evenly split or in other words, 6 ÷ 249w = 41.5w per cob? It seems the wattage isn't necessarily reflective of light output though. That is more about what amp is used is that right?

Then the second number, for example 1400mA or 1.4amps, relates to how many lumens I can get from each cob or how hard to drive them based on Cree specs?

My confusion lies in the driver model numbers don't seem to coincide with driver output for the individual driver but refer to a "mean" wattage through the series depending on the mA number (or not) which seems to be accurate. The 240-1400 is actually 249w at 1.4amps.

So then, when you drive cobs at lower amps, you can fit more cob's on a single driver? That what it seems the spreadsheets refer to. The amps seem to be constant hence constant current so accuracy of this number is critical?

If that's the case then I could drive more cob's softer with the same or greater lumens per square foot and lower wattage draw? But in doing so, I would be sacrificing efficiency?

I should just stfu and build what your suggesting, and probably will lol, but I like to understand things. Hope it's not too annoying. my avatar should make sense now lol!

Thank you for indulging me. I'm just trying to get this from weeks of study.

doz said:

You can run veg with the lights, but I do not. I was using a T5 for veg, but I am building a 200w CXB3590 5000k light. If you want to veg and flower, I would go with 3500k or 4000k for a happy median.

I also do not dim my lights. I have not found a need to as they plants have always done well under full power. True power draw from the wall is 442w with BOTH lights. They draw 221w each.

I run 10 plants in my area 2x5 area. I am not currently running as I am moving in a week, but new setup will be much better. I top them I think 3 times on both runs (HPS and LED). I personally do not feel plant count is a big deal. I can run 3 plants in my area and grow them larger, or run 10 smaller. You just have to veg longer w/ 3 plants. 10 plants cuts down on veg time.

As far as the pot size comparison, I did do multiple pot sizes in the same area, same amount of plants. The 5 gallon did do a bit better than 3 gallon, but I am not sure its worth the extra cost of soil in the end. I would definitely use 3gal over 2gal though. And use 5gal if you plan on growing less plants in your same area (or even 7gal). SOrry for the late response, not sure how I missed it @Humanrob .

Click to expand...

Doz, I hope the move went well. Did you get set up again and are you doing another grow?

I'm just under a week into 12/12 on my first run done start to finish under my DIY COB light. I picked up some clones and started them under 200w -- (2) 5000k + (2) 4000k. Up until now I'd keep them under CFLs until about a week after they were up-potted into 1gal. pots. I started with the light about has high as it would go in my tent, probably 4' over the babies.

At this point I'm running the full 400w, having flipped on the (4) 3000k lights after up-potting them into their final pots. This is all a big experiment, but I'm keeping my lights pretty high. I'm in a very basic FFOF/Happy Frog soil mix with mostly time release nutes and cal-mag, and the plants seem happier with more distance from the lights, they are currently 24"-30". They do seem happy though. Because I'm not slamming them with nutes, I don't think they can keep up with too much light intensity, so I wouldn't be surprised if I weren't dimming mine if they grow tall enough that proximity becomes an issue.

I would rather run 2 or 3 in the tent, but I'm doing four now, and because of logistical reasons/floor space issues, I'm running the two bigger ones in 5gal and the two smaller in 3gal pots (two were gotten a week after the others). We'll see how that goes, I've never run smaller than 7 gallon so far. This is also the shortest veg time I've ever done, I usually go six weeks, this time I went 3/4 weeks.

Quick question -- when you run 10 small ones instead of 3 large ones, while I understand you are saying overall yield is similar in weight, do you find the buds are smaller? I'm thinking that having fewer plants that vegged longer would give me fewer but larger colas... which is less to "process" come harvest. For me, that's the way I'd rather go.

I look forward to hearing about your next run --

giantsfan24 said:

Ok so it's the watts of the driver, in this case just slightly under 250, ÷ by the number of cob's is how you're coming up with 49.8w per cob?

I know I'm focusing on watts here but bear with me... Because 5 cob's is the most this driver can "fit" as far as efficientcy is concerned, (I hope I got that right) if I got a driver, hypothetically, that fit 6 cob's at the same wattage but only used 5 cobs, would the wattage still be evenly split or in other words, 6 ÷ 249w = 41.5w per cob? It seems the wattage isn't necessarily reflective of light output though. That is more about what amp is used is that right?

Then the second number, for example 1400mA or 1.4amps, relates to how many lumens I can get from each cob or how hard to drive them based on Cree specs?

My confusion lies in the driver model numbers don't seem to coincide with driver output for the individual driver but refer to a "mean" wattage through the series depending on the mA number (or not) which seems to be accurate. The 240-1400 is actually 249w at 1.4amps.

So then, when you drive cobs at lower amps, you can fit more cob's on a single driver? That what it seems the spreadsheets refer to. The amps seem to be constant hence constant current so accuracy of this number is critical?

If that's the case then I could drive more cob's softer with the same or greater lumens per square foot and lower wattage draw? But in doing so, I would be sacrificing efficiency?

I should just stfu and build what your suggesting, and probably will lol, but I like to understand things. Hope it's not too annoying. my avatar should make sense now lol!

Thank you for indulging me. I'm just trying to get this from weeks of study.

Click to expand...

Wattage is the cobs forward voltage X mA. 34-36v X 1.4 = 49-50W

Airwalker16 said:

Wattage is the cobs forward voltage X mA. 34-36v X 1.4 = 49-50W

Click to expand...

Right ( not that I knew that ) but isn't it the case that is the full potential watts of each cob ( power draw ) is dependent on how it's driven? Wouldn't a 50w cob dimmed 50% be 25w effectively?