Advice please - 12v or 36v led drivers for diy cob build

Northernpop

Well-Known Member
Hi Guys,

I'm trying to build a cob grow system for my small grow room, but I'm financially embarrassed.

It's only 2 x 3ft in size, so I was looking at something around the 200-300w range.

With this in mind, could I build a cheap diy cob system with 12v drivers and chips, or do I need to stick to 36v DC ?

Many thanks, as always.

Happy growing !!
 

1212ham

Well-Known Member
Driver voltage needs to match cob voltage. Most cobs are 36v or more. Citizen are probably the lowest cost, high quality cabs. There are cheap cobs available, but they will be low efficiency and unknown reliability. Cheapest build of good quality is probably Samsung F-series or Biridgelux EB strips. Something like $130 USD for 250W. http://ledgardener.com/diy-led-strip-build-designs-samsung-bridgelux/#more-2416. Something like $130 USD for 250W.
 

Northernpop

Well-Known Member
Driver voltage needs to match cob voltage. Most cobs are 36v or more. Citizen are probably the lowest cost, high quality cabs. There are cheap cobs available, but they will be low efficiency and unknown reliability. Cheapest build of good quality is probably Samsung F-series or Biridgelux EB strips. Something like $130 USD for 250W. http://ledgardener.com/diy-led-strip-build-designs-samsung-bridgelux/#more-2416. Something like $130 USD for 250W.
That's great. I'll look into it 1212ham. Cheers pal
 

Northernpop

Well-Known Member
I was hoping to do it for under £100 and I think I've found second hand heatsinks that should be ok for a 50w Citizen cob. I've attached the heatsink for you to see. I don't know how to work out heatsinks per wattage of cob.

Any thoughts, or links would be sweet pal.IMG_3939.PNGIMG_3938.PNG

These are only £9 each, but will they work? I've got soldering kit, rivet gun, etc... so I don't mind tinkering.

Peace out.
 

Randomblame

Well-Known Member
Too small for 50w passiv and far too expensive! Look for Intel 1154 coolers the ones with copper core(e3ay). You can get them in 10packs for very cheap(less than 50$/10pcs). But you will need a 5v/2A driver to drive the fans, I like the 3-12v wallplug drivers because you can use various voltages for different fan speeds.

But why not strips, mate?
EBgen.2 strips don't need a heatsink! You need to mount them on a frame, but wether thermal grease nor heatsinks are needed. This saves you a lot and strips are probably more efficient too. You can get them in 1, 2 or 4' length, the 2footers max out at ~29w(20,5v/1,4A) and the 4 footers at 58w(41v/1,4A).
I would recommend to use a 1050 or 1,4A driver to keep the costs down. You can expect 170lm/w or 2,4μMol/J at 1050mA, thats really good numbers for such a cheap build.
And do not forget, it will work at least 5-7years without visible loss! And the higher upfront costs(100 vs. 130$)you have in again after the first round!
 

Northernpop

Well-Known Member
Too small for 50w passiv and far too expensive! Look for Intel 1154 coolers the ones with copper core(e3ay). You can get them in 10packs for very cheap(less than 50$/10pcs). But you will need a 5v/2A driver to drive the fans, I like the 3-12v wallplug drivers because you can use various voltages for different fan speeds.

But why not strips, mate?
EBgen.2 strips don't need a heatsink! You need to mount them on a frame, but wether thermal grease nor heatsinks are needed. This saves you a lot and strips are probably more efficient too. You can get them in 1, 2 or 4' length, the 2footers max out at ~29w(20,5v/1,4A) and the 4 footers at 58w(41v/1,4A).
I would recommend to use a 1050 or 1,4A driver to keep the costs down. You can expect 170lm/w or 2,4μMol/J at 1050mA, thats really good numbers for such a cheap build.
And do not forget, it will work at least 5-7years without visible loss! And the higher upfront costs(100 vs. 130$)you have in again after the first round!
Cheers Randomblame. I currently have a fairly poor light system, with a Chinese 1000w alledged light with two inbuilt fans that drive me crazy, and 4 x 60w corn grow lights. These fans are not very stealth, so I really don't want fans. My sons exgirlfirend heard them and figured it out, but they parted on good terms so phew. My room is only 2 x 3 ft in size too.

My profile pic is my room last August with northern lights about ready.

Any advice is appreciated.
 

diyled

Well-Known Member
I take it you're in the uk by saying £100 budget. You can do it for £130ish

elg-240-48a/b = £38 (tme.eu)
4x doublerow f series = £92 (digikey)

The rest is easy to find.
4x U profile aluminium.= Find a local metal shop and they will have a off cut or scrap bin with a size close enough and cut this for you for cheap. Just get atleast 40mm wide.
Ac wiring just buy/find a kettle lead and chop the end off.
dc wiring is a couple quid.

If you have a soldiring iron and a rivet gun you wont need bolts/wagos/ac connector. Just hardwire/fix it all.
 

Dave455

Well-Known Member
I was hoping to do it for under £100 and I think I've found second hand heatsinks that should be ok for a 50w Citizen cob. I've attached the heatsink for you to see. I don't know how to work out heatsinks per wattage of cob.

Any thoughts, or links would be sweet pal.View attachment 4113112View attachment 4113113

These are only £9 each, but will they work? I've got soldering kit, rivet gun, etc... so I don't mind tinkering.

Peace out.
Get some quantum board 132's ...no heat sink needed and call it a day..
 

Northernpop

Well-Known Member
Cheers Dave, but quantum boards don't seem available in the uk. Don't know why.

Also, cheers diyled. This is what I'm wanting to build. I've found the driver, but can't find the doublerow f series on digikey. Please could you give me the code/description?

Many thanks !!
 

Northernpop

Well-Known Member
Awesome diyled ! Cheers pal. So do these strips fix to an aluminium frame? Are they easy to wire? Which light would you recommend please?

Happy growing.
 

diyled

Well-Known Member
Yes you can use double sided thermal tape to fix them to the aluminium U profile. Then a couple of bits of L profile to attach them too.

It involves a bit of diy but for your budget thats the best option really.

Check out this site its got a guide for everything. http://ledgardener.com/diy-guides/

If you need any help just give us a shout.
 

diyled

Well-Known Member
It will pull 250 watts at the wall. It will add vat ontop of that price you are in the uk arent you?

The Aluminium U profile acts as the heatsink its just a cheap way of doing it.
 

diyled

Well-Known Member
You need the 48v Constant voltage driver.

Onboard dimming Link
Dimming via potentiometer link

You might find them cheaper if you shop around as tme charge postage.
 

1212ham

Well-Known Member
Cheers Randomblame. I currently have a fairly poor light system, with a Chinese 1000w alledged light with two inbuilt fans that drive me crazy, and 4 x 60w corn grow lights.
Looks like you have an excellent build worked out. (:

Just an FYI, often the driver and other parts are worth salvaging from cheap lights. Also, many cheap lights are worth upgrading with new cobs.
 

Northernpop

Well-Known Member
Looks like you have an excellent build worked out. (:

Just an FYI, often the driver and other parts are worth salvaging from cheap lights. Also, many cheap lights are worth upgrading with new cobs.
Hey, I didn't even think of that. The grow is ok, but the fans in the 1000w led do my head in. Need to silence the room.
 
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