O-M-G It's Here

[PetFlora]

Surfin the net for where to buy cobs I came across this DIY thread

IMO, no need for the E27s as overheads. Instead, position them so the sockets/bulbs face down. Add extenders and they are perfect for side/below canopy lighting


Feast your eyes on this...



http://howtogrowmarijuana.com/DIY-LED-grow-light
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[Morcheeba*]

thx

 

[wantaknow]

nice find ,this guys has a great approach to this

 

[sammyz2646]

This is a fantastic idea!!! I researched the parts and its not that awful bad. For a few clicks and a little bit of easy labor, you could have a very effective, super bright and upgradable unit that would probably go for stupid $$$$ in the retail market with a shiny hood covering it and some companies logo.

I have never thought of trying to build a light, but this is inspiring.

My biggest fear is the wiring end of things

 

[sammyz2646]

Not to mention that your light hood could be of variable size and shape tailored to your needs, i.e. spreading things out for more coverage, etc

What would the size limitations be on your new light???

What would be the chains weakest link in engineering a larger type light?

Maybe the wiring would limit this. Didn't know if too many LED units wired together would even be applicable?

 

[Phatlewtz]

Your only real limit is how many watts you want to use..I suppose space could be a limiter.

 

[sammyz2646]

I wonder if I chose to go the Meanwell route for the best efficiency , which one???

 

[3dDream]

sammyz2646, The CEN or HLG "A" if you want to dim it off the driver. I have a single cree cxa3050 hooked to a cen-100-42.

 

[PetFlora]

Here, it's even simpler

I emailed them and asked about driver draw and actual cob draw as many of these are ~ 50%: also whether they can be made with Molex - so we can quickly replace cobs

Anyway check this out for < $75/5 (+ you can mix) you can either supplement or do a small area grow

http://www.aliexpress.com/store/pro...ool-White-Nature-white/207403_1559686250.html

 

[sammyz2646]

sammyz2646, The CEN or HLG "A" if you want to dim it off the driver. I have a single cree cxa3050 hooked to a cen-100-42.

Hey there, 3d, so I was thinking of trying exactly what you did.
I wanted to try a sample to experiment with and make all early errors on a SINGLE COB.

Just out of curiosity, is your single cob fairly bright?

How hard is the wiring of the driver and power cord, etc?



Forgive me, as I am NOT very experienced with tedious wiring, etc
I am not a huge DIY guy as my time in a day simply does not allow for hours upon hours of wiring, glueing, and soldering.

Having said that, if you guys here can help, I would LOVE to save some money and certainly would love to BEAT most of the current fixtures available today at the moment

 

[PetFlora]

These are adjustable, excellent for better below canopy penetration

http://www.aliexpress.com/item/5Pcs...warm-white-white-free-express/1703514218.html

 

[3dDream]

sammyz2646

Just out of curiosity, is your single cob fairly bright?

It is bright and covers a wide area. I don't know if this single cob will be enough for a whole grow or not, time will tell. I am just setting up a micro grow with it now and my seedlings are a week old. Everything stretched being 3+ feet away. The 1 foot range is the sweet spot and where I have it now. In my head I think this cob is equal to 5-6 25W CFLS. (if that means anything to you)

How hard is the wiring of the driver and power cord, etc?

I imagine it is much easier than wiring a dozen 3w leds. This is why I liked the cobs. Got the power cord at the local hardware store and attached it to the driver. The driver comes ready to attach with the wires pre-stripped and soldered. The other end of the driver needs a cable to attach to the cob. Lamp wire or any two wires will do. Be sure that no wires come close to being in front of the led, they will cook if they do. It does generate lots of heat. Get yourself a big hunk of aluminum or a heavy heatsink. If you want active cooling most PC heatsinks are rated for 100W of cooling.

 

[sammyz2646]

Alright 3D! From what your saying, this is really basic wiring. I never tried to build anything like this, but COMMON SENSE play a big role in my life, (unlike so many others), and Im feeling like this may be an option for NOW, today's technology.
Thnak you sir for your input and response

I may order the separate components and try just the one cob, but my plans will be multiple COB's and a wider frame with a wider footprint, accompanied by a few smaller room fans to keep the air circulating nicely around the unit, assuming I continue with a fanless unit

 

[3dDream]

sammyz2646 - Good luck! I just want to stress again how a good heatsink can make all the difference. I thought mine would be big enough and it gets a little hotter than I like (I wanted it warm to the touch at the highest power). I hope you get a beastly one to run passive cooling. The cooler you run it the brighter it is and the longer it will last. This would be running the cob at 185 F or 85 C. Pretty hot! Cree has great info about the cob:

See heatsinks here:
http://www.cree.com/~/media/Files/C...mp Application Notes/CXA3050_Thermal_Load.pdf

http://www.cree.com/LED-Components-and-Modules/Products/XLamp/Arrays-NonDirectional/XLamp-CXA3050

Heatsinks:

There are Chinese 100w star shaped heatsinks on ebay. They only weigh 2 pounds though. I don't know what temps these could keep them at. If you search for "100w heatsink" you will see them.

Then there is this guy, but it would have cost me about $60 for the heatsink I wanted:
http://heatsinkusa.com/

These guys make some beasts, but I could not find where to buy them:
http://www.heatsinkled.com/led_heat_sinks/LED_passive_heat_sinks/

Another:

http://www.ledgroupbuy.com/heatsink-10-inch/

 

[sammyz2646]

Thanks again for all your helpful information 3D

I have so much more information now to guide myself through this process. Having someone vouch for the heat impacts etc. is vital so we know which pieces will work best for the future project. Links are always appreciated as well!!!



BTW, did you try the same heatsink as the guy in the article did at 1st?

The Giorgio 11185? This isn't big enough?????

 

[3dDream]

I ended up getting something from a local scrap. I could not beat the price and it is 8" square with 2" fins, anodized, and weighs about 7 lbs. Old dead amps and old servers are your friend.

Giorgio 11185 100w heatsink is 2lbs last I checked. If it works, it works, but it sounds a little pricey.

BTW one last thing, I am driving 100W to the CXA3050, the guy in the link in the first post is running each cob at 28w.

 

[sammyz2646]

Hey there 3d, your help here has been immense, for that, thank you.

So I ordered the Giorgio XXL heatsink and also ordered the CXA-3050, and the thermal fabric recently mention by Pet in another discussion. (To try my 1st DIY unit)

A few questions to you or anyone else who may know:

1- How hard would it to add a small parabolic reflector to this array? And would it create any unintended issues? (HEAT)

2- With the Cen driver you use (3d), will running this COB (CXA 3050), at that wattage, will it last? Just wondering why the DIY guy ran his so low @ 28 watts. Maybe to prolong life and/or keep the heat at bay?? Do you think I should run it at a lower wattage? Which driver would be best?
I like the dimming capability of the other driver you mentioned 3d, but wow, spendy

 

[PetFlora]

I found some interesting links one is a 100w COB the other a n easy to install bonding mat

http://www.electronicproducts.com/T...mal_interface_material_performs_like_gel.aspx

http://www.amazon.com/Zitrades-Whit...sbs_hi_40?ie=UTF8&refRID=1VES8EB1KAYA6GN9TK54

 

[sammyz2646]

Hey Pet (or anyone else), what are your thoughts on this?? How in the heck would you even start to keep this cool enough?

Giant heat sink with a giant fan?


http://www.topledlight.com/200w300w-cree-xlamp-xpg-xpg-white-high-power-led-copper-pcb_p1497.html

But, I'd be willing to bet that this little puppy would do good things

I saw a 500 watt warm white COB somewhere else on this website, not Cree though

BTW, I am anxiously awaiting my parts to build the CXA 3050 single chip lamp

 

[3dDream]

sammyz2646 - The cen dims within a range. It does not go totally dark. It is enough that at the lowest my heatsink is almost room temp and when turn all the way up my heatsink is hot to the touch. The HLG ( model A) driver is more efficient and has buttons for the dimming. I have not used it. I did not want to spend the extra $$. These drivers are pricey, you could go with chinese drivers off ebay, but you really aren't saving much. I like the idea of using this driver in the future when better cobs come out. Because the voltage and amps have a range there is a bit of wiggle room for future LEDs.

Can you drill holes in a heatsink to mount it? If you can there are reflectors out there. Because the cxa3050 shoots out at a wide beam I did not think one was needed. Plus you lose a bit of intensity adding a reflector.

If you don't mind a fan then go with a pc heatsink rated for 100w. I wanted to go passive and to stay in the proper temps I need a big hunk of aluminum.

I don't think the Giorgio will be big enough for 100w, but I am just guessing. Do you have a laser thermometer? if you can get access to one be sure to read the cob. If you want the LED to last then you need to keep it within spec.