Economical multi LED Chip Projects for Growing

[DIY-HP-LED]

I'm starting this thread to document some recent LED grow light experiments and build projects using multi LED chips and drivers purchased off of ebay. While these systems don't have the efficiency of CREE or other brand name chips, they can none the less grow very good plants. The operating costs may be higher than the brand name chips, but you can get started for under $50 in most cases and switch out the chips to higher quality ones later if you want. Here are some examples of the kind of chips I'm talking about:
The top chip is a 100W Grow chip Bridgelux full spectrum 400nm~840nm
The middle chip is a 100W Warm White High Power LED
The bottom chip is a 100W Cool White High Power LED

 

[DIY-HP-LED]

The first project uses a Genesis (generic) Warm White chip and the other uses a Full Spectrum 400nm- 840nm LED Grow Chip (See the links above too). I'm using 3A current limiting driver boards that run on line voltage and output 30-36 VDC. To drive the 12 volt fans, I'm using 99 cent DC to DC converters (not shown) that scavenge power from the led driver output. I can easily adjust the speed of the fan by turning the voltage up or down via a potentiometer on the DC-DC converter board.

The lights are housed in a couple of old metal kitchen canisters and suspended with chains. I've put a thermal cut off switch (60 C) in series with the on/off switch for safety.

 

[DIY-HP-LED]

Here are a few more pictures of the "canister light" on the bench, just before closing up and testing. You can see the small DC to DC converter board mounted on the side of the fan in all the pictures. The LED driver is mounted on the top of the case with some "L" brackets, an old PC CPU heat sink and fan cools everything. The LED chip uses a 2" dia. metalized plastic reflector and collimator lens that they claim only absorbs 2% of the light. Readings with a simple plant light meter proved that the lens doubled the light intensity at 3 ft (1M) when compared to the reflector alone. The shape of the intensely bright light cone produced by the reflector/lens is perfectly suited to grow one plant. The light is very penetrating, but I'm gonna use side lighting as well. These types of chips produce 9000 to 11,000 lumens and one should use sunglasses when working with them because they will dazzle ya. It reminds me of looking at a welding arc!

To draw DC power for the fan, I soldered 2 wires onto the LED terminals leading to the DC to DC voltage converter for the fan. I can adjust the speed of the fan by adjusting the output voltage with a potentiometer on the DC to DC converter The 100watt LED is supplied by a constant current driver (3A 30-36VDC) that runs on AC line voltage. I haven't measured it yet, but they claim that the chip/driver only consumes 70-80 watts. The major components of the lamp: LED chip, driver and DC to DC converter only cost about $35, most of the rest was scrounged free junk, an old canister set and a scrap PC.

 

[DIY-HP-LED]

And here are a few pictures of components and the lights in action.

 

[DIY-HP-LED]

A quick up date. I've since doubled both of the canister lights, meaning I added another LED chip so that each light now has 2 LEDs running in parallel off of a single 100 watt driver. Most LED manufactures aren't exactly honest about the power of their LEDs and the actual power used by the chip is usually much lower than the advertised power. For instance a 100 watt Chinese Bridgelux design actually only draws 73 watts of power from a non adjustable driver.

On the canister lights I used an adjustable driver and with a single Chinese generic Genesis LED chip, the most power I could get the thing to draw was 56 watts (37.7V x 1.5A). So I doubled the chips and wired them in parallel from the same driver. Now I get 33.5V X 3A = 100 watts of power consumed by both chips plus about 30mA by the fan and an almost doubling of the light output. To add another chip I screwed a 1/4" X 5" X5" aluminum plate to the bottom of the heat sink as a heat spreader and attached the chips to the plate with screws. Both chips use reflectors and lenses to focus and concentrate the light.

So, if your going to be using 100 watt cheap Chinese generic Genesis LED chips in your build, use 2 chips (in parallel) per 100 watt driver to get the most out of your driver. Always make sure the driver is cooled by the heat sink fan air flow, since the cooler the driver runs the longer it lasts. The LED chips are cheap and by under driving them slightly they become more efficient at turning electricity into light.

I now have about 550 actual watts of DIY LED light on the garden and can say these cool white generic chips are producing rapid growth and some nice buds, so far.

 

[DiyKindaGuy]

Can you post pics please

Sent from my SGH-I747M using Rollitup mobile app

 

[SupraSPL]

Good experimentation DHL. I was confused about the first link you posted, do you get (60) 100W chips for $38? Interesting method to power the fans, they convert constant current from the LED driver into constant voltage for the fan?

I might have to try something like this or this to do the same thing and get 5V power for the fans. It would be interesting to see what kind of efficiency I could get from it.

So I suppose the big question would be, how would this 550W DIY LED compare against a quality 600W HPS in terms of cost, heat and efficiency?

 

[ballist]

My last led grow was very similar and I ran a 600w hps in another tent. I wasn't around for the last couple of weeks of the grow either but the numbers given by the wife after harvest put the led tent slightly ahead for yield. Interesting the best yielding plant started flowering under hps for the first 10 days then was moved to the led side. It was 70g dry of BF lsd.

 

[DIY-HP-LED]

Can you post pics please

Sent from my SGH-I747M using Rollitup mobile app

I'll try to get some batteries in the camera and take a few pics soon

 

[sethimus]

did you buy the canisters or did you already had them? if bought, from where exactly? your design looks really nice, like it a lot!

 

[nomofatum]

Cool, I'm using the same type COBs, just using the 30w version (and just warm/cool colors), 5 per 100w for me. No fans just a big aluminum rack for my cooling. I picked the 30w size so I could spread the light and heat around easier and use cheaper cooling (passive aluminum rack [mix of aluminum channel and angle] near the exhaust and wall fans.)

 

[Positivity]

This is the best example of using budget leds i've seen yet..awesome job

This is how its done...put up the parts used, how you use them, and your experience with them. End of flower pics would be helpful but i can understand if not. Learned more here in one page than the other "discussions" combined

 

[DIY-HP-LED]

Good experimentation DHL. I was confused about the first link you posted, do you get (60) 100W chips for $38? Interesting method to power the fans, they convert constant current from the LED driver into constant voltage for the fan?

I might have to try something like this or this to do the same thing and get 5V power for the fans. It would be interesting to see what kind of efficiency I could get from it.

So I suppose the big question would be, how would this 550W DIY LED compare against a quality 600W HPS in terms of cost, heat and efficiency?

I buy my 100 watt generic chips off ebay and prices are always dropping, I think I paid as low as $6 for generics, about $20. for a 100 W cool white Bridgelux and around $40. for the 100W full spectrum grow chip. Fixed output 100 W constant current drivers run around $20 each and will run 1X 100w Bridgelux @ about 76 watts. The same driver will run a cheap Chinese 100w chip @ 56 watts, if I put two of these chips in parallel on the same driver, the power output goes up to 100 watts and the light emitted goes up by 64% (simple plant light meter & warm white LED).

Usually the efficiency of DC to DC converters drops with a greater difference between the input and output voltages and the amount of load. A typical 5V fan should use much less than a watt of power, in fact, for a 5v fan to use a watt of energy it would have to be running at 2 amps! So efficiency shouldn't come into play unless your counting nano-cents on yer power bill! My lamps use 12v 80mm fans that usually draw about .25ma and I often run them at around 9-10v, so 10V X .25A = 2.5 watts. I've ordered some 120vac to 12vdc 1A converters in small metal boxes for a couple of bucks each, to draw fan power from the AC side of things for some future applications.

As for stacking up against a 600w HID lamp, I'd say very favorably and heat is no problem. Cost of 2 x cheap LEDs, lens/reflectors, AC driver & DC to DC converter, are about $40 per doubled lamp.

 

[DIY-HP-LED]

Here is a family photo of a few of my LED projects doing what they were designed to do.

The 2 canister lights at the bottom L & R have been doubled with 2 x 100 watt cool white generic chips running in parallel off of one 100 watt adjustable driver.

The 2 black lamps in the front top with the reddish light are full spectrum grow chips, the one on the left is 100w (running at 76w) and the one on the right is a 120w chip running off a 100w driver and drawing about 100w. The old CPU heat sinks and the drivers are housed in free scrap ATX computer supplies (common as dirt). If the heat sink fins point the right way you can even use the fans in the ATX power supply boxes to cool everything. The reflectors are dollar store cat dishes with a hole in the center to contain the lenses. The cat dish reflectors are redundant and in further builds I won't use them with a lens/reflector. This type of lamp fixture can easily be double chipped (using cheap generic chips) with a heat spreader plate screwed onto a PC heat sink. They use fixed drivers like those shown above attached to the boxes with electrical wire ties.

The center light uses a Chinese 100w Bridgelux design chip that draws about 75 watts off of a fixed 3A driver. I just put a couple of dabs of dollar store epoxy on the reflector to hold it onto the chip, I never used a lens on this light since I want to spread the light a bit more. I used the PC heat sink and fan in this one and drilled some large holes in the top for extra ventilation.

The LED chips used in the lamps in this photo consume about 450 watts of power. I have another 100 watt lamp on the garden that I'll show next post, most growers should be interested in that one, it's a bit special.

BTW: The plants are 1 month into flower, the one the left is Pink Kush and the right is OG Kush. This is just a test grow using small DIY air punning pots made from plastic dollar store waste paper baskets and geo textile (garden weed barrier cloth). I'm testing these chips, air pruning pots and the Kush's of course.

 

[DIY-HP-LED]

Here is a Fan Lamp that uses 2 x 100 watt generic warm white chips running off one 100 watt driver. The heat sink and chips are mounted on the front bottom of the fan cage and the driver is mounted on the top back of the fan cage. I used a piece of an old computer case to contain the driver, but if you want to keep it simple use a water proof IP67 driver in it's own box and mount it on the fan cage, a bit more expensive, but easier. I have connectors on the wires between the driver and the LED for ease of maintenance and cleaning. I made a reflector from self adhesive plastic mirror pieces bought from the dollar store. Every garden has a fan, why not use it to cool an LED array. This is a test rig and I'm gonna build a better one with 4 chips and 2 drivers on a new fan. The oscillating mechanism on my fan doesn't work quite right and I don't use it now. I did test it though and it works very well as a light mover. This lamp is great for growing out those bottom buds, between the blowing leaves and the changing light angle there aren't many shadows.

 

[DIY-HP-LED]

 

[nomofatum]

You make some damn pretty DIY, great job. I like the ingenuity mixed with the creative thinking you have here.

 

[DIY-HP-LED]

 

[nomofatum]

You need to stop posting pictures, take these down and go into business.

(should just be taken as a compliment if you have no interest)

 

[DIY-HP-LED]

did you buy the canisters or did you already had them? if bought, from where exactly? your design looks really nice, like it a lot!

The canisters are probably 60's vintage, bought at a yard sale. Any metal container large enough is suitable for building a lamp, old computer power supplies are what I've mostly used, but you could use a metal cake or cookie box. I'm currently working on a build using an old junk Colman propane camping stove that should contain 6 100W LED chips. You should use metal containers for your lamps or use enclosed drivers for fire safety reasons. I always solder and heat shrink tube all connections and use grommets on power cords etc. Good connections are important in low voltage/ high amperage DC applications inorder to avoid heated connections and power loss.