Lighting COB LED INFORMATION check it out!!!

[Atulip]

Depends on what the shipping comes to, but in the long run passive cooling is cheaper than active cooling.

 

[Dion]

Depends on what the shipping comes to, but in the long run passive cooling is cheaper than active cooling.

not to mention bumping system efficency up a few %

eg 50w led that is 50% eff(cxb3070 @ 1400mA) so 25 par watts


vs same set up with 3w of fan still 25 par watts but only 47% eff huge drop

 

[brokencage]

Being primarily an autoflowering enthusiasts site, I also have to toss out that most dedicated auto growers run anywhere from 18/6 to 24/0 on/off cycles with their lights, so that would also shorten the ROI time frame a bit versus the 2.6 years number you came to for the 12/12 lighting. :smoking:

thanks for that I feel a little better now.

 

[KonopCh]

not to mention bumping system efficency up a few %

eg 50w led that is 50% eff(cxb3070 @ 1400mA) so 25 par watts


vs same set up with 3w of fan still 25 par watts but only 47% eff huge drop

What about lifespan, is active better, right?

 

[Dion]

What about lifespan, is active better, right?

life span depends on Tj so no if u have a big enough passive heatsink

 

[KonopCh]

@Dion bigger/better heatsink, lower Tj. Or it isn't that?
Or it's current (mA) biggest/only one factor?

 

[Dion]

@Dion bigger/better heatsink, lower Tj. Or it isn't that?
Or it's current (mA) biggest/only one factor?

well its not liner

lets say you have an LED that is 50% efficent at 50w(cxb3070) that means you have 25w oƒ heat produced so you need a heatsink that can disapate 25w of heat... if u run passive(no fan) you need 110cm2 per heat watt if active you need 40cm2 per heat watt

so for this cob you would need 2750cm2 of surface area for passive or 1000cm2 for active cooling to maintain aproximately 50 Tj

now if we ran the current at say 2000mA the eff would drop to around 45% and now we are running it at like 75W so 55% of that becomes heat so 41.25 watts of heat so need a bigger heatsink

 

[Anasazi]

Anyone have any good links for guides? I want to try and build a light for a small grow space and hopefully keeping the price under 150$ lol. No clue where to really start.

 

[orrganic]

Anyone have any good links for guides? I want to try and build a light for a small grow space and hopefully keeping the price under 150$ lol. No clue where to really start.

Im on a similar budget bro, in a 1x1m2. so stay tuned. And the best start for a guide is growmau5 on youtube his diy led beginners guide is invaluable.

@BigSm0 Yo! Iv'e been looking around and clearly the 3590 are top dawg but thats over budget, 2530 look great but what about higher and lower powered units than the 2530 are any of those worth a shot? I've already got and onl cp heatsink so its just driver and cobs and im set!

also i know roughly what driver i need/want but only small discrepencies in numbers or letters to do with w\a\v\ model so on and so forth..
im looking at MW HLG -240H-c1050A and on ebay their is one going cheap second hand that i want to pull the trigger on but it is a c1050(B) not A and i dont know the difference yet any help would be appreiciated guys!

 

[keep pounding]

the b version can be dimmable. has a 2 wire lead for hooking up a pentiometer/dimmer. this 2 wire can be left unhooked and the driver will operate at 100%+.
me personally would buy from dist. and not ebay, that place and used electronics scares me. but maybe worth the risk.
that is all I have hope it helps