Airwalker16
Well-Known Member
I fuckin payed $43 a piece for my 8 cree cxb3590's. I'd pay $50 for them.
Introducing CobKits.com - specializing in DIY and Citizen COBs
Airwalker16
Well-Known Member
Because the 3590 & 3070 are fairly similar despite the smaller LES. So it's kinda weird that the 48 is such a step down
CobKits
Well-Known Member
ok how many CXBs do you want at $50?
step down in what? it outperforms the CXBs
it has more to do with number of dies than LES size. the 1818s have 324 dies, not sure about a CXB
I'll still fighting with either 4 1818s or 10-16 1212s running at 10w.
What's the simplest solution to cooling the 1212s running at 10w? The efficiency intrigues me. I would still want holders for ease of setting up.
4x2 grow area. Anyone have guides on calculating efficiency of lights? I think it's time I start diving into the technical side of things =/
What's the simplest solution to cooling the 1212s running at 10w? The efficiency intrigues me. I would still want holders for ease of setting up.
4x2 grow area. Anyone have guides on calculating efficiency of lights? I think it's time I start diving into the technical side of things =/
CobKits
Well-Known Member
@bggrass 's most awesome java-based calculators
https://www.dropbox.com/s/hqgj9n5qxb9xrei/DIYCOBLEDCalculator.jar?dl=0
https://www.dropbox.com/s/2s0xo583lw10m29/CitiCalculator.jar?dl=0
https://www.dropbox.com/s/hqgj9n5qxb9xrei/DIYCOBLEDCalculator.jar?dl=0
https://www.dropbox.com/s/2s0xo583lw10m29/CitiCalculator.jar?dl=0
PhotonFUD
Well-Known Member
Seriously though, think about the 20 1212s. Think of it this way:
1. You have 20 chips. You can spread them out nicely 3:2:1 2700:3000:4000k CCT ratio
It is only a few watts of heat each, so you can dangle them.
Too hard to believe? Stick them on pretty much anything with some bubble gum.
Real men use crazy glue as TIM!
But yeah, 1212s for the price are the best so far. The vero 7c has huge promise. Gertian (?) looks good as well.
Going to have haters, but I measured some cheap chinese cobs for PAR and they are off a good 30-40% at higher watts but when you run them lower, the gap narrows a lot. Will investigate more.
1. You have 20 chips. You can spread them out nicely 3:2:1 2700:3000:4000k CCT ratio
It is only a few watts of heat each, so you can dangle them.
Too hard to believe? Stick them on pretty much anything with some bubble gum.
Real men use crazy glue as TIM!
But yeah, 1212s for the price are the best so far. The vero 7c has huge promise. Gertian (?) looks good as well.
Going to have haters, but I measured some cheap chinese cobs for PAR and they are off a good 30-40% at higher watts but when you run them lower, the gap narrows a lot. Will investigate more.
Rocket Soul
Well-Known Member
If youre not sure what you want as final setup u can also think about wiring in paralell. But you would still need to chose between 1818 and 1212 before you start as you need to get the voltage right. How tall is your growspace? For your basic 1818 setup on high watts thru each chip you will need some clearance at least 12-18''. If you have the height go for 1818, if not go for 1212.
Get a driver(s) with the right voltage and wattage for your space, about 250 to 350, cobby has for the 1818, not sure if he has for 1212. Setup your cobs connected in paralell, that means they will share the amps that coming from the driver equally. If you want more spread and efficiency 6 months down the road, get more cobs and connect again paralell. This way u can get as many cobs as u want on a driver with increaing spread and efficiency as watts go down per cob.
Downside: paralell is not recommended always, as if one cob dies, the other ones will take the juice from the dead cob. If you have your setup nicely tuned with some extra capacity with heatsinks and max amp on the cob, no problem, but if you havent you might end up with one cob failing, and the rest failing as consequnce. Sounds really bad, right? But entirely avoidable if you make sure you got enough heatsinks capacity on every cob. And generally if its setup by a pro, like cobby, i wouldnt worry about it. Go for the light engine and save yourself some problems, its probably going to cost you more to get it done yourself.
Example: for high clearance
4 1818 on 2hlg185 48, 2 on each driver
4x65+2x45=320, 288 with RIU discount, plus shipping. Later on you could add another 4 when you have the dough, running 4 of them per driver for aprox 60% efficiency, 50watt per cob, you could even stop using the fans on the heatsinks.
Or for low clearance, say you get 3 hlg120 36volt version. Put 2 1212 on each of them running them at 60 watts each. Not too efficient but if you bang another 2 on each driver once you have some more money you get a pretty sweet setup. Cant say what it would cost as youd prob need drivers from someone else, 6 1212 light engines would be around 300, maybe better value to buy the chips and mount them yourself.
I love learning about all of this stuff, thank you very much for your time!
I have plenty of height so that's not an issue.
So what exactly is a light engine? I was under the impression it replaced drivers, but I guess I was wrong.
Why not series over parallel if parallel has those issues?
As far as heatsinks, I can make sure they're cooled properly. Will get a pin fins. If I'm aiming for efficiency, how many 1818s should I get, and what should I drive them at? Also heatsinks, what thermal resistance would I need at the recommended amps?
Cost will be much higher for the "accessories" if I go for many 1212s I think.
PhotonFUD
Well-Known Member
The concerns about running parallel are from the old days when the method was to over drive current. Going the other way, parallel is perfect for underdriving. Especially if each chip you are using is capable of handling the full load of the driver by itself in the event the others fail.
Rocket Soul
Well-Known Member
Light engine here would be a unit thats ready to be connected to the driver, connections and heatsinks etc all mounted and setup. For doing that work you would need soldering station, a fixed drillpress (is that what its called) all the cables, holder, optics etc: a lot of stuff. Also factor in the possibility that you mess up the soldering a ruin a chip. The 1818 and 1825 are really good value, i looked around and not found anything much cheaper, with quality and easy setup.
Running in paralell/series: paralell for flexibility, just adding cobs for better spread and efficiency. You would still have the same watts going thru your system, just adding efficiency as you add cobs. The risk of all of them dying on you is near 0 if you use tge light engine as the heatsink should handle the extra heat, should handle up to 200watts. Also when manufacturers recommend not running in paralell its more down to achieving even ligjt intensity as cobs can vary slightly in voltage.
Series: more expensive drivers and you dont get the same possibility to add cobs as u go on, you need to think this is my final setup. I went for series anyway, as thats what made sense at the time and for the space (laaaarge). Not sure if i regret it now, maybe when i get my second space, which is different, i would go that way.
Pin heatsinks: great, especially if they are going to have your ventilation on it. Makes a 2 in 1. But you need to do soldering yourself unless theres solderless holders available.
If you wanna do bars from heatsinkusa for example go for at least 10mm base.
My advice: 4 1818 light engines in paralell on 2 hlg185 48A, dimmable, and when you have the dough, upgrade to 8.
Fits your first budget and will light the space fine. And also let you upgrade to 8 cobs for more efficiency in the future, for 200 and a bit. You get something nice and no hassle to setup for only marginally more cost than total diy.
If you google rollitup grow northern photon 180 theres a couple of threads/grows with a very similar light as 2 of these light engines, only in 1825 instead of 1818, but at less wattage per cob.
Check all these details with cobby first as id rather rely on him than me
Rocket Soul
Well-Known Member
Depends on area to cover, height of canopy and how much clearance you have ontop. Just check the example above and do 3 cobs per driver. But it would cost you more than 125 per fixture. Could probably be done with diffrent drivers and 1212 but then u probably would source the driver from someome else. Reallys cratching at the edges ofwhats possible on that budget. Add another 75-100 per fixture and your golden
PhotonFUD
Well-Known Member
10 1212s per array. Scavenge some drivers.
verticalgrow
Well-Known Member
VG
Slyslain
Member
Thanks for the replies.
More details may help give direction so...
The coverage area is 4x3x4
I thinking I'll need 200w but maybe 150w is enough per array.
Maybe even 100w is enough.
I have a cheap 300w(140w draw) led panel in. 2x2x4, works fine but for the new box I want better lights
The box is mainly for flower but don't want to rule out vegging in it.
More details may help give direction so...
The coverage area is 4x3x4
I thinking I'll need 200w but maybe 150w is enough per array.
Maybe even 100w is enough.
I have a cheap 300w(140w draw) led panel in. 2x2x4, works fine but for the new box I want better lights
The box is mainly for flower but don't want to rule out vegging in it.
Rocket Soul
Well-Known Member
For so low clearance id go with 1212s, the more the merrier, and around 35+ watts per square foot. You can do 3500k as it veg and flower great. 2700k many complain on stretch, which you dont have space for.
Slyslain
Member
Haha ya no room for the stretch. Good to know 3500k will do well.
So if 1212s are best for my situation, how many can I put on a driver and what driver to use lol.
MrTwist1
Well-Known Member
Just read back through the thread a few posts - this has been answered I think.
Rocket Soul
Well-Known Member
1050 mAmp driver, hlg240 will take 6 and hlg320 will take 8, i think. Better checking this stuff with cobby. And please note the stickied thread on the led forum diy leds and how to power them. Read up to make sure all i told you isnt bullshit. What i give are opinions but its a good idea how to makebur own
PhotonFUD
Well-Known Member
Easy to solve with a regular led bulb 4000k, 5000k, etc. Just pop one in for vegging, has enough blue.