REALSTYLES 6th DIY CXA 3590 5000k DB bin

OneHitDone

Well-Known Member
I envy u so much. I want/need one badjy. The heat is the biggest problem I have with a DE open fixture I have to run a 8000btu window to keep things at optimal temps and that's killing my power bill bad! But I'm going to start with a veg lite build so I will be more comfortable with the heatsink work. Any advice u or anyone else that has built a cob would be great! How many 3095's should I use and at what spread to get my plants noded up rightly for a 1000w flowering light? If I went passive, what size heat sinks should I use. Hook a fellow grower up with some knowledge so I can have a nice veg lite.

Happy growing,
Green217
I think your going to find out heat is going to be easier to manage if you put that DE lamp in a hood such as the AC/DE by sun sytems. You are going to have the same heat build up issue with led.
Everyone has agreed. 600W, 800W, 1000W = x amount of heat no matter the light source
 

BigYellowCob

Well-Known Member
I think your going to find out heat is going to be easier to manage if you put that DE lamp in a hood such as the AC/DE by sun sytems. You are going to have the same heat build up issue with led.
Everyone has agreed. 600W, 800W, 1000W = x amount of heat no matter the light source
True that 1000w of LED will produce the same heat as 1000w HPS. But if you run an efficient COB setup and can produce the same number of photons at the canopy with 600w of LED as you'd get with 1000w of HPS, then you have 400w less heat to manage.
 

green217

Well-Known Member
Actually its running fine with no hood in my room just have to use the big ac, I really don't want to buy a hood to put it in so I'm going to just roll with it. I can get it within 30 inches of the plants and keep it at 80 degrees at canopy, that's good enough for me. With no hood. This part of the world the temperatures are about to drop and that makes life easier. 30 inches is as close as I need with that double ended 1000 watt fixture. Changing my air condition unit out - 8000 BTU corrected the problem.
 
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green217

Well-Known Member
I think your going to find out heat is going to be easier to manage if you put that DE lamp in a hood such as the AC/DE by sun sytems. You are going to have the same heat build up issue with led.
Everyone has agreed. 600W, 800W, 1000W = x amount of heat no matter the light source
Honestly I learned something there, I didn't know to 1000 watts of LED will produce the same amount of heat as 1000 watts of HPS. For some reason I thought temperature wouldn't be happening much of a factor with the heat sinks
 

OneHitDone

Well-Known Member
I had to scratch my head a minute on that one myself. All I could think was how is a 1000W A/C unit going to make the same heat as a 1000W space heater.
Probably not the most scientific but if you put the A/C unit in a box all the heat coming out of the condenser end would overwhelm what it is cooling. That heat would normally be blown outside the space being cooled.
I am not promoting any type of light over another and just taking stabs at things trying different lighting sources till I find my preference.
I will tell you that a 460W Inda-gro/pontoon combo was contributing more heat to my 5x5 grow box than the 1000W HPS I am testing in there now. The ability to move the Heat out with a dedicated ducting system is something the led companied need to be looking at.
There is 1 or two diy led grows set up that way and those guys are on to somthing
 

alesh

Well-Known Member
The link doesnt work....I still want to understand how to calculate things myself. Being able to read a chart doesnt give understanding to how get the number....what if you cant find a chart lol....or the links broken ;P

Was my math wrong there? I need to be able to figure out these things to come up with my own led/driver combos. Right now my first build is based off supraspl's posts (12) cxb3590 3500k 36v on 3 HLG-185h-c1400b. So for one driver w/ (4) 36v cobs is 144v. 200w max output / 1.4amps = 142.8v....it seems that Im a little off or its normal to be off by a couple volts? lol

Also I guess I should rephrase the question, what kinda hps are we would this be comparable to ? a 600w hps?
I know 600w hps would be adequate to light a 3x3 or 4x4 foot print. So roughly what footrpint would be reasonable with this light?
Ahh sorry MW site doesn't allow hotlinking...

The output region of a driver isn't something you calculate, it's set by the manufacturer. The data sheet is the correct place to find it.
 

EfficientWatt

Well-Known Member
Wow, a lot of confusion here....I'll take a stab at it if I may.

1000W of 56% efficienct leds will give off 440W of heat "straight away". The 560W of energy converted into light will mostly end up as heat in the end, too.

1000W of 28% efficient MH will give off 720W of heat, and the 280W of light will be eventually converted to mostly heat, too

BUT, having 2 times more usuable light will result in more being absorbed by the plants, and more space covered with the leds (at equal ppfd)
More light/w means more space/W = lower temperatures.

I guess in an empty room, both would end up producing 100% heat from their Watts ... but with plants, yes, you will have lower temperatures with more efficient lamps.

NO, 1000W with 1% efficiency will not give you the same temperature as a 60% efficient 1000W as long as plants are capturing some of that light ..

i fix that for you
generally a 1000 watts of leds will produce less Temperature in the grow room than a 1000watt hid.

Heat ≠ Temperature
Learn about it.
Care to elaborate?
 
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bicit

Well-Known Member
i fix that for you
generally a 1000 watts of leds will produce less Temperature in the grow room than a 1000watt hid.

Heat ≠ Temperature
Learn about it.
Even that isn't really true. 1kw of power is 4000 btu, no matter what its from. The same amount of energy has to be extracted from the system in order to maintain a temperature equalibrium within the system.
 

PurpleBuz

Well-Known Member
Even that isn't really true. 1kw of power is 4000 btu, no matter what its from. .
while that statement is true ...

your both full of shit, cause the more usable light produced by a lamp less energy is released as heat into the grow space. which was the whole point of my statement.

the heat of an object is the total energy of all the molecular motion inside that object. Temperature, on the other hand, is a measure of the average heat or thermal energy of the molecules in a substance.
seems guod got it ass backwards.
 
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