Cheap cobs

ttystikk

ttystikk

Well-Known Member
heckler73 said:
That's essentially the grand point I was trying to raise. But I can be comfortable saying Zhong Guo Cheapos will give 12khrs anyway (+/- 2khrs) . So I presume that is a safe estimate for any DIY rig. :-?
But I was fairly sure someone like SDS or Supra have been running theirs for that long. Then again, many COBs seem to get changed like tires in F1-racing around here. Everyone is trying to sit on the bleeding edge :lol:
Click to expand...
It's cool that people like to test chips to their limits and report back on what works and what doesn't.

Racing improves the breed, right?
 
zep_lover

zep_lover

Well-Known Member
my first diy cobs were with chinese 100 watt cobs run at 50 watt.i used arctic 11 heat sinks.and cheap ebay 50 watt drivers.i ended up using them in my veg cabinet mounted in between my vero 10 veg light.i just finished building 5 cxb 3590 lights with 4 cobs per light using same drivers as the chinese cobs.there is no comparision to the chinese warm white cobs and the cxb 3590 3500k.the cxb blows the chinese cobs away.i had only put the chinese cobs (3) in with my diy vero 10 light to get more stretch and more penetration as the plants get bigger before being moved to the flower cabinet.
the vero ten light(100 watts) with the 3 chinese cobs added (150 watts) is distant second to the cxb light in how plants look and how bright
.the cxb light is drawing 212 watts from the wall and the vero chinese rig is drawing over 260
if you want to go cheap i would use the vero 29.half the cost of cxb 3590
 
McCheeze

McCheeze

Member
Because of budget problems I'm gonna have to use the cheap chips and upgrade later. My whole setup is gonna be a poor man's grow wife has given me a budget of $100 for everything. But I'm sure as time goes on a plant grows she will let me have a lil bigger budget
 
zep_lover

zep_lover

Well-Known Member
good luck.it might be easier to just use led bulbs from home depot.they have had alot of the led bulbs marked very low lately
 
littlejacob

littlejacob

Well-Known Member
QUOTE="McCheeze, post: 12282978, member: 922173"]Because of budget problems I'm gonna have to use the cheap chips and upgrade later. My whole setup is gonna be a poor man's grow wife has given me a budget of $100 for everything. But I'm sure as time goes on a plant grows she will let me have a lil bigger budget[/QUOTE]
Bonjour
For 1 plant try cxa2530 @700mA X 4...I guess 1 cost 8 $ and a driver around 30 $ plus cpu hs...or even vero13
CU
 
ttystikk

ttystikk

Well-Known Member
zep_lover said:
my first diy cobs were with chinese 100 watt cobs run at 50 watt.i used arctic 11 heat sinks.and cheap ebay 50 watt drivers.i ended up using them in my veg cabinet mounted in between my vero 10 veg light.i just finished building 5 cxb 3590 lights with 4 cobs per light using same drivers as the chinese cobs.there is no comparision to the chinese warm white cobs and the cxb 3590 3500k.the cxb blows the chinese cobs away.i had only put the chinese cobs (3) in with my diy vero 10 light to get more stretch and more penetration as the plants get bigger before being moved to the flower cabinet.
the vero ten light(100 watts) with the 3 chinese cobs added (150 watts) is distant second to the cxb light in how plants look and how bright
.the cxb light is drawing 212 watts from the wall and the vero chinese rig is drawing over 260
if you want to go cheap i would use the vero 29.half the cost of cxb 3590
Click to expand...
I'm running the same combo you are; four CXB3590 300K @50W apiece per module. I've put a couple of mine up so far and they're hands down the finest light for growing plants I've yet used, period. I can't wait to get the rest up and running!
 
stardustsailor

stardustsailor

Well-Known Member
heckler73 said:
That's essentially the grand point I was trying to raise. But I can be comfortable saying Zhong Guo Cheapos will give 12khrs anyway (+/- 2khrs) . So I presume that is a safe estimate for any DIY rig. :-?
But I was fairly sure someone like SDS or Supra have been running theirs for that long. Then again, many COBs seem to get changed like tires in F1-racing around here. Everyone is trying to sit on the bleeding edge :lol:
Click to expand...
Solid State ...Service Life ,is absolutely dependant from cooling ...
Whether we're referring to LED chips (thus COBs ) ,MOSFETs or any other solid state device ...

For COBs there's another factor determining service life ,of lesser importance than cooling ...
Every LES is made of silicone of some sort (there are two different types mainly used ,at the moment *)
which is a semi-permeable material to gases and water vapour ..
Depending on LES material,thickness and surface area and of course the environment variables ,
the service life of a COB may be decreased ,even if efficient cooling is utilised ..
But that is a very complex issue to be analysed ,for the moment being ...


* ( phenyl & methyl silicones .For more info google " LED encapsulating silicone material " )

Cheers.
:peace:
 
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heckler73

heckler73

Well-Known Member
stardustsailor said:
For COBs there's another factor determining service life ,of lesser importance than cooling ...
Every LES is made of silicone of some sort (there are two different types mainly used ,at the moment *)
which is a semi-permeable material to gases and water vapour .
Click to expand...


I have considered that (I read the threads where it was brought up, earlier). I honestly don't perceive that to be a serious factor in relation, unless one is doing unusual things with them; however, I still don't have enough info on the matter to definitively say it is not a problem.

Coincidentally, looking at a presentation from DOW-Corning (see link later), they acknowledge that issue's effect on phosphor quenching but quickly point out "heat and light" cause the gases to escape leading to "LED recovery" (NB. phosphor temps can exceed Tj). So unless one is leaving their exposed siloxanes in a harsh environment for extended periods (i.e. more than the typical grower's) it doesn't appear to be that serious. I suppose one situation which could be a problem is if condensation is allowed to form on them during dark periods, then firing them up with the droplets on them still. Hmmm...sounds like an interesting experiment, actually :lol:

Thermal effects are quite serious though, since they can (and do) alter the refractive index.

See slide 6 in the following for photographed examples.
http://apps1.eere.energy.gov/buildings/publications/pdfs/ssl/deshazer_silicones_sandiego2014.pdf
Even at 65degC (6000hrs) , there is some serious yellowing happening.
And sticking them in bottles of sulfur for 20 hours at 80degC? Not a good idea (at least for the methyl type). :mrgreen:
 
GANJA MONSTA

GANJA MONSTA

Member
Hello Gardeners!

I am trying extremely hard to upgrade my grow. Currently I use CFL's but they do not penetrate beneath the canopy or produce enough lumens. So I've been trying to find a affordable, powerful, and hopefully long lasting light. I realize that is asking a lot, so "long lasting" isn't a requirement.

I have a couple of questions regarding COB's & LED's.

1) Has anyone ever heard of the company GEMA Grow Light LED? If so what have you heard and/or know about their lights?
I believe that they are a Chinese based company, so I am very reluctant to spend any money without good reason to believe that the light will work well.

2) The link I am providing below will bring you to GEMA Grow Light LED's "new COB light" if you have the time please follow the link and have a look; I am a beginner so I wasn't aware that blurple COB's existed, I assumed that all COB's produced a full spectrum white/natural light. My question is this; do you know if the COB light from GEMA is worth buying? Or do you know of a better COB or LED grow light that is approximately in the same price range as GEMA's

https://www.gemaledgrowlight.com/collections/popular-items-with-free-shipping/products/new-cob-led-grow-light-full-spectrum-600w-1200w-1800w-2400w-for-indoor-medical-plants-grow-veg-and-bloom?customer_posted=true#contact_form

Thank you all very much for your time and help!!
 
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