HOW TO BUILD AN LED GROWLIGHT

[KAOS]

Got most of the parts for the 2540 build (4000k colour temp). I am still waiting for the 60W drivers so fired them up with some 50W units.
 
It runs super cool at 31C after 30min so hoping with the 60W drivers it will stay below 40C.
 
Forgive the 'raw' state of the build, but it has to be disassembled when the new drivers arrive anyway.
 
With all new parts (still have to buy fans) it works out to about $75USD and generates 13000 lux at 50cm (130W from the socket).
 
My 'go to' light is a full spectrum white 1500W COB unit (230W from the socket) and interestingly that outputs the same lux, but at 76% higher power usage.
 
In $$$ terms assuming 16hrs per day at 25c/kwh the 1500W unit costs $0.92 per day vs the 2540's at $0.52 - In theory the build will pay for itself in 267 days.
 
Might need to rethink the setup now ....

 

 

 

[KAOS]

Finally got round to tidying up the 2540 build with the new 60W drivers.

Using 165W from the socket at pf 0.98 and generating 15000 lux at 50cm.

Temps are 32deg C after 15min so I’m happy there’s some breathing space.

Sent from my iPhone using Tapatalk

 

[KAOS]

Latest incarnation from the lab ...
 
1 x Meanwell ELG-240-C2100B driver
6 x Cree 2540's (4 x4000k , 2 x 5000k)
2 x NZXT 140mm fans
1 x 12V1A fan supply
A fair chunk of aluminium
Wiring, switch, 100kPot and other bits and pieces
 
Variable power from 25W to 250W
Lux - Not measured yet, but estimating around 22500 lux at 50 cm.
 
Cost to build around $150USD
 
Waiting on a descent power switch and still deciding on how I'm going to hang it
 

 

 

[lespaulde]

Thanks to all the inspiration in this thread, I finally decided to also take the plunge and build myself a LED light. After hours of searching for currently best setup for COBs, many forums were pointing to the efficiency of the led strips / quantum boards, so I spent many more hours researching how to strike a good balance between light output, power usage and cost of parts. My goal was mainly for starting seedlings in the spring, and perhaps to keep a plant or two going for an additional month or so after the summer to ripen the last batch of pods. Of course I could have just bought a quantum board + driver and be done with it, but what would have been the fun in that? Besides, I was hoping to get a little more spread out of my light so I could cover a larger area.


End results of parts ordered were the following:

2x SI-B8R261560WW (LT-F562B, 5000k)

2x SI-B8T261560WW (LT-F562B, 4000k)

1x HLG-185H-24A (~190W driver, which is overkill for 4 strips, but allows expansion with at least 2 more strips if needed, and was basically the same price as the 150W driver)

Some U-channel aluminium as heatsinks, and L-channel aluminium for the frame.

Total price of parts was a little over 100USD plus tax, or around 100EUR, so quite affordable for the light output I’d say, and the same, if not a little cheaper, than buying ready-built quantum boards.

In the current configuration, these strips have the same number of leds (288 total) as a single quantum board, and them being the same samsung LM561C diodes, should result in the same benefits, except for the fact that I was now able to mix the 4000k and 5000k spectra to hopefully obtain the best of both worlds for pepper growing.

I’m running the strips, in parallel, at 1,200mA, resulting in a total current draw of 4.8A, meaning around 120W pulled at the wall. According to Samsung’s calculator, this gives just under 20,000 lumens at an efficacy of 174lm/w, and let me tell you they are bright! After about 2hrs of running, temps are at a steady 50C, so could probably push the strips a little harder, but I think this should suffice. I've also put a 1,600mA glass fuse in front of each strip, in order to prevent any current runaway higher than what the strips can handle (1,800mA). This shouldn't be necessary but adds a nice layer of security and peace of mind...

Unfortunately the pictures don’t do the brightness justice, but I think you get the gist of it…  

Sent from my HTC One using Tapatalk

 

[nice.chili]

Nice build!    Great use of the Samsung strips.
 
That single plant is sure going to do well.
(And +10 points for using the clothes drying rack. Who needs that for it's original purpose anyway!    )

 

[lespaulde]

Nice build!    Great use of the Samsung strips.
 
That single plant is sure going to do well.
(And +10 points for using the clothes drying rack. Who needs that for it's original purpose anyway!    )

Thanks, I think they are definitely a good fit for this purpose, and they run nice and cool. I can highly recommend ledgardener.com for details as he has helped make things very clear indeed. Especially in terms of driver selection etc., and explaining why the "A" type driver is so useful in terms of dimming etc.
 
And hahaha, if I really went through all that trouble for one single plant, there'd be seriously something wrong with me... Although, truth be told, that plant was only a mere seedling 1 week ago, so the light is definitely powerful... Just kidding, I couldn't resist at the plant nursery the other week, as the Bhut Jolokia Purple was originally on my grow list for 2018 but got bumped. This way I at least got seeds for next year, AND it made a nice showcase for the pic. And lol, I'm not sure my better half would agree with me using the drying rack, but again, it was for illustration purposes only.    Will probably get a small grow tent to put it in, as it otherwise lights up the room too much.