Tag Archives: LED

DIY 130 W LED light Feat. The crescience FLUxEngine

Video with build instructions

This article will cover how to build a solderless LED light thats scalable and very easy to set up. Check out why LEDs are superior.

The build shown here is beginner friendly. You dont have to drill into metal and the boards do not need active or passive cooling, since the framing will be sufficient to do that. If youre more into COBs, check out my 310W COB growlight guide!

This article will cover how to build a solderless LED light thats scalable and very easy to set up. Read more about how LEDs are superior.

Disclaimer: This piece of electronic is a potential fire hazard and should only be put together by electricians or persons with similar know-how. Please refrain from putting in self-made electronics into the wallplug. Dont die!


For this build you can either buy the whole kit from the LED builders website, or you look for a bunch of groove profiles from metal dealer thats suitable for you. Mind that I cant give an amazon link for that, since the orders are most likely to be custom made.

Groove Profile – use these, so you dont have to drill into metal!

I used 30 cm and 38 cm long profiles with a 4cmx4cm crosssection, so you can build a square-shape out of it.

You also need a bunch of metal sliders. Make sure, that the sliders fit the profiles.

Metal sliders that are needed as holes for the screws.

Every slider needs a fitting screw aswell. To connect the framepieces You will also need some angles. There has to be one on the side where you will buy the framing that fits the profile. It should look somewhat like that:

Angle connector for the frame.

For this particular build I used 4 FLUXengines to achieve a total power of 130 W for the 2×2 tent its used in. Be aware, that these boards might require screws with a smaller head, so you dont drill onto the LED modules.

FLUXengine with the power connector in the front and the Samsung lm301b chips on board.

The ELG-150-24A driver is the connection between the wallplug and the boards. You will need one of these. The boards are connected in parallel.

The driver!

You will also need about 50 cm to 1 m of single core copper cables to connect every board with the driver. I suggest you buy two different colors: one for plus, and one for minus. The cross-section of the wire should be between 0.14 mm² and 0.5 mm². Mind that once you used 0.5mm² cables on the connectors, you will not be able to switcht to the smaller ones.

Single core copper cables are easy to clamp!

For further connections and cable collection you will also need to buy WAGO clamps. Two 5-way clamps to connect all the boards in parallel to the driver, and three 2-ways to connect the driver to plug cable for the wall.

Wago Clamps for cable connection.

Last but not least its important to hang the lights from the top of the tent. Get four hook screws in order to do that.

Use these to hang your light!

Take some measurements first

Lay down your frames in front of you and put the boards on top in a symmetrical way. After that you estimate the cable lengths and cut them. Strip the isolation and connect the cables color-coded to + and to the boards and guide them throught the aluminum profiles. Its better to take longer cut here, hust to be save.

After that you take your metal sliders and also guide them through the profiles. You can now screw the boards tightly to the to the frames, and the framepieces to each other. Before you screw together the frame pieces, make sure to have all sliders in the back installed aswell. You wont be able to access the shorter parts anymore or you have to unscrew everything…

Connecting the cables

The schematic shows how its done. Collect all minus and plus cables together and put them into a 5-way WAGO clamp each. The voltage delivered by the driver stays constant while the current gets forced to a maximum output of about 6.3 A.

All cables are connected, the light is hanging safely – time to grow!

Testing and mounting

Four Crescience FLUXengine modules haning in the tent

When everything is connected nice and tight, you can now plug it in and look if it runs. Dont look directly into the light.

Done! This light should draw around 130 W at the wall and is able to light up a 60cm x 60cm grow tent (2’x2′).

Scale up!

The four modules can also be connected to a bigger drivers. Each module is able to put out 60W of light, so if you have the ability to hold down temps, you can also use ELG 240-42 running at 5710 mA to reach about 230 W with this setup. Mind that these chips run hotter and less efficient in this configuration, but will still crush any blurple or HPS lights in comparison.

COB LED Lights Simplified

Build your own COB LED light – the absolute basics

DIY COB light – 310 W optimal for a 9 ft² space

Cool, so you are interested in building your own light? Here is what you need to know! We dive a bit into LED tech and how to design a simple circuit, that will enable you to choose the parts for your grow LED to your individual needs. You will also learn about the importance of reading datasheets.

Disclaimer: Please please please DO NOT try to connect any selfbuilt circuits to your electrical circuit at home without being 100 % sure that what you build is OKAY. It is easy to kill yourself in the process if you do anything wrong.

Why even consider building a LED grow light yourself?!

Good grow LED tech is expensive. With 2-4 $ per Watt you can end up paying thousands of dollars on the best lights.
The advantage of this is mostly, that you get a finished plug&play module with things like warranty and product testing. In the case of DIY LED Kits sold by Horticulture Lighting Group, this is not the case. The sets you buy there are great, but its way cheaper to build them on your own.

Comapnies like Timber Growlights or Pro Emit are selling complete builds out of these items. Yes, they are companies, and therefore need to make a profit. But with a little insight and help, you will be able to but together a high quality LED grow light yourself for about 1$ per Watt or even less.

Why LEDs are superior

This is the future.

Wiliam Texier, “Hydroponics for everyone”, Chapter about LEDs

LED tech is advancing at an enormous speed. Companies producing LED light fixtures have to deal with this and need to apply very fast, to not fall behind. Almost every other month there is a new chip out there crushing all numbers that were there before.
LED light is semiconductor technology. Without going any way into solid state physics you can try to imagine that electrical energy gets used to push electrons into another state where they can recombine to a energetic more favorable position. The excess energy  of this recombination is then emitted as light. This is a very efficient process. In 2006 the first LED by Nichia with a light yield of 150 lm/W, equal to the output of HPS lamps. 

Disclaimer: Lumen per Watt is actually not a good way to compare LED and HPS lights. LEDs and HPS have different spectra and Lumen favors lights with more green light, because it weights the spectra with the so called luminosity function. The high output in the yellow/red range of a HPS light is not favored as much as a full spectrum white light from a 3500K LED.

Since then alot has happened. Current tech pushes the the light yield way beyond the 200 lm/W levels for Quantum Board chips (LM301b or LM561c). Current record holder is Cree with 303 lm/W with a 5150K (Cold white) LED chip. (cool tech, but not suitable for growing)

The spectrum of a warm white LED at 3000K or 3500K is also way better to reproduce the McCree intensity distribution to induce photosynthesis than HPS lights. 
HPS lights also tend to heat up alot. Modern Quantum Boards as well as COB lights can be cooled passively with heatsinks. That saves even more power, since air conditioning could potentially cost alot of money in an operation if the room gets too hot.

spectral properties of different lights
A grow light should reproduce the McCree curve as  accurately as possible. HPS light has a spectrum that is fairly limited to yellow and red wavelengths (upper right), while LED light is able to distribute energy to all the wavelengths needed (lower three spectra).

In comparison to HPS, CMH or LEC light, high quality LED systems are still pretty expensive. In the long run, a high quality system will be much superior in that regard, compared to the rest.

The Current Circuit

Current flows when they its enabled to do so by the existence of voltage. LEDs need a distinct workpoint, a combination of direct voltage and current to work efficiently.

The power plug in your house gives usually gives you between 110 V (U.S.) and 230 V (EU) and up to 12 A to 16 A of current before the fuse will have a serious word with you. Short circuits are just a unhinged connection between two poles creating a big ass current peak. The fuse will jump out and the light goes of.

So the first thing you will need is a driver.

Transforming electricity with a driver

To transform the alternating voltage to a usable direct voltage you need (over simplifed)three things: A transformator , capacitor and a rectifier. All of these things are included in a driver. Since you manipulate a form of energy this driver will never be 100% efficient. Good drivers will work with an efficiency of more than 90% though.

The Transformator will change the value of the incoming voltage, while the rectifier is used to reverse the part of the waveform that has the wrong signum. The capacitor is used to smooth out the curve and to fine tune the process. There is much more than this happening in a LED driver, but this is the basic principle. 

Schematic of a rectifier
Simplified circuit: The pink waveform is already rectified. The capacitor C smoothes out the form further to create the rippled curve above. If you use more than one capacitor, you can ease this out even further. 

Important: NEVER connect LEDs to the power plug of your home without a driver. Could end lethal.

The right combination of Drivers and COB modules

Okay, now that we can safely convert our electrical input, we can now proceed and choose the right combination of light modules and drivers.
First you should determine the amount of power you will need in the end. 

Since you will build an awesome high quality COB light you will need about 35 Watt of power per squarefoot.

Example one: A 3’x3′ tent light

For this setup we need approximately 315 Watt of high quality COB light. (3 x 3=9, 9 x 35 = 315)

The BXRC-35E10K0-D-73-SE is the perfect canditate for that. It will run with a current of 2.1 A at a voltage of 36.6 V. Power is determined by multiplying these two values, resulting in 76.86 W for each COB. So running four of them will yield 307.84 W, which is close enough to the desired 315 W we need.
The COB delivers hell of a light!
Since we know, that lumen are not really useful to determine light quality, its an okay ballpark number to compare lights with similiar spectra (3500 K).
This light runs at 147lm/W @ 2.1A and 36.6V

COB efficiency

One quick notice: A COB runs less effecient the more current you push through it. You will get a better lm/W value if you run just 1.4 A. This will result in less power and less absolute photon output, but a cooler COB and higher efficiency. So if you plan to build more efficient, you want to consider to use more COBs at less current.

Now that we got our lights, we need a driver, that can run them properly. For this purpose we need to plan the configuration of the lights we are using. Lets assume we connect all 4 COBs in series. In 9th grade in school you learn about Kirchhoff’s circuirt laws, that tells you: The current in a series connection is constant. On the other hand the voltages will have to be added together.
Conclusion: We need a driver with an output of 2.1 A and 146.4 V.

series connection of 4 cobs
Series connection of 4 COBs

The most common drivers on the market right now are from MeanWell.
The model HLG-320H-C2100B will deliver a constant current of 2100 mA = 2.1A and has an output voltage ranging from 76 V to 152 V which is quite perfect for our cause, because we calculated with 146.4 V!
The driver costs about $100 plus $80 for the COBs. Not a bad starting point for a 310 W light!
You will need some more items before you plug in your light and let it shine on your ladies. (Build guide coming soon)

Setup for the Avid smoker – The 3×3 grow tent

Grow tent in full flower
You can do this, with a setup described in this section. Source: homegrow-pro.com

Everything you need to harvest  10 oz. of dry material every 3-4 months!
I will list the items that are absolute mandatory to grow first. There is a list with additional items, that I deem useful below. Get started on your first grow tent!

General Assumptions

  • Your grow medium of choice is soil.
  • You grow in a grow tent.
  • You start from seed.
  • You are a grow enthusiast who wants to make the most of a given space.
  • You do not have to run this hobby on a budget. (Options for that below)

List of items

grow tent3×3 Grow Tent1$90amazon
light*400W COB Light 1$600timbergrowlights
pots3 gal airpots4$50amazon
soil*60l specialized soil1$15 – $30(see below)
nutrition*Trypack1$15(see below)
ventilationClip Fans1-2$10-$20amazon
clima controlTemp./Hum. Monitor1$3amazon
on/off switchProgammable timer1$12amazon
  • Tents are great to keep control of every aspect. You can change temperatur, brightness, humidity and even simulate seasons in there! Its absolutely necessary to get your tent completely dark to your needs. If you have a closet or a room where you can manage to create pitch black darkness, you dont need a tent. The brand of the tent does not really matter. 
  • Light: Your articficial sun. Good growlights are hard to find in the LED jungle. Read more about lights below.
  • Pots: They come in different varieties. Plastic, fabric, with holes in it from 0.5 to 30 gal. I choose the airpots, because they let air move through the soil, and roots are pruned naturally at the outlets, preventing root rot or rootbound plants.
  • Soil: Do not buy common gardening soil. Cannabis roots need space to roam. Specialized cannabis soil has the right consistency and is often perfectly balanced with nutrition. You can also cook your own soil!
  • Nutrition: Personal opinion about nutrition – as long as its marketed for cannabis and does not kill your plants every brand seems legit. It is more like a personal decision what kind of nutes you use…
  • Ventilation: Moving air prevents bud rot and keeps the branches moving. That creates resistance and your plant will grow thicker and stringer. Keep the vents on 24/7.
  • Filter system: Your main exchange for air. If you have to grow stealthy or at home you do not want to have the smell leave the tent. Get one of these asap.
  • Clima Control: Really important to keep track of your values in there. You want to know the numbers. Once you know its over 34°C in your tent all the time, you know its time to do something about it. Same with humidity.
  • On/Off switch: Over the course of 100 days of a grow you dont want to hit the switches twice a day at the same time. Automate that.


The light

Yes, the light is the most expensive item in a grow operation. Yes, you can save money on light, but this is the best option for a grow room of that size. Its cool, quiet and runs damn bright. It has the most recent technology behind it and does not need extra cooling. But there are alternatives.

PRO TIP: You need at least 35W/ft² of high quality LED/COB light or at least 50W/ft² if you use CMH/HPS lights, if you want max out the tent potential! There are thousands of options. Just make sure its a grow light. Spectrum, PAR, PPFD values and color of light are also important properties. Read everything about the theory behind light here.

Alternative 1 – The Quantum Board

Horticulturelightinggroup.com has a very decent 320 Watt kit. It has alot of advantages like better light distributions or overall efficiency. I just did not link it as first option because it only has 320 Watts, and we wanted to get the most of our room with the given conditions. If you are able to build these lights yourself with a kit, buy these! The magic behind Quantum boards are LM56c or LM301b LED chips from Samsung. If you can find other distributors using these chips, you can go for it.

Grow tent with a quantum board
Quantum boards have an exceptional efficiency and overall light distribution!

Alternative 2 – Other LED Distributors

Its true, Timbergrowlights is just an option when in comes to LED lights. There are several chips out there that are awesome to grow weed with.
Timber makes use of Citizen CLU048, Cree CXB3590 and Vero29 COB LEDs. But other companies do it aswell!
Cobshop.net has a 3×3 kit including 4 COBs for $480, but they dont disclose how many Watts you get in the end. I assume its 200 W, so only half of my first option.

Alternative 3 – Low Budget only

I will list them here only because they work. But do not expect wonders. Im talking about the infamous blue/purple or pink lights you find on amazon.
NO, they almost NEVER deliver the amount of power they have in their names, NO you dont need just one, but at least 3 of these “300W” varieties you find online. Which one you take does not really matter, they are all ok. They only use the cheapest LED technology, including chips and drivers. If you spend $210 on three of them, you will be able to light up your tent properly. But remember to tune up the ventilation system, because three of these bad boys run pretty hot in a 3×3.

Blurple light tent
Blurple lights – They just won’t leave me alone! Low costs – low yields.

Alternative 4 – HPS lights

A 600 W HPS light will get you pretty far in a tent like this. And it costs only $130. This can reduce the inital cost significantly, but keep in mind that these light run HOT. And by that i mean shit-i-might-need-an-AC-in-my-tent HOT. The price is low, but running this shit can cost you! Save some money, ditch the AC and the pay only 2/3 to run a sweet LED light in there and pay less for your production.

Alternative 5 – Build your own COB or Quantum Board light

www.ledgardener.com, is the best source for that. There will be a guide here soon….

Soil and nutrition – Globalization and availability

If you live in Europe you have different soil companies than in the US. So while you can buy BioBizz in Europe pretty cheap, it is better to choose Fox Farm. 

The right soil is very important for your grow. Your roots want a pretty loosy, oxygenated environment. Many soil companies put peat (turf) in their soil which is very harmful to the environment. Check the ingredients, if you want to save the planet.

EU soil recommendations

US soil companies


Same with as soil. It seems like there is a new nutrition company out there every week. Even the breeder try to jump on the nute train and handing out their own nutrition along the seeds. (Royal Queen Seeds and Green House Seeds for example.)

I will also only recommend nutrition that have an organic base. I just do not believe in chemicals, but thats up for discussion.

EU nutrition recommendations

US nutrition recommendations

Useful additions

There are a lot more items making your tent easier. These are nice to have, but not 100% necessary. This list is not not yet completed.


  • Depending on your method of germination you will need papertowels or kitchen paper.
  • Since germination needs a dark, moist and warm environment, you might need a propagation box. I just put them in an old cookiebox on my PC.
  • Do not touch seeds! Use a tweezer.

Seedling and vegetative stage

  • Seedlings do not need flooded with water. Use a pump sprayer and be careful!
  • If you plan to train your plants, you need gardening wires or metal stakes. Or anything else you can come up with. You can also just use a cord and bind them down.
  • Use sharp scissors, knifes or even scalpels to cut leafs!
  • If you see pests like mites or thripes, treat them with bio degradable organic insecticide. Be careful with that!

Flowering stage

  • Some genetics produce fat buds. Too fat to hold them in place. Use plant yoyos or bamboo sticks and wire to hold them in place.
  • If you see any pests in the flowering stage do not spray the buds with insecticide. Use predatory bugs to fight them. This is your chance to have a personal ladybug army in your garden.
  • Jewelers loupes help you watching the trichomes and help to determine the harvest window.

Harvest, Drying and Curing