Indoor gardening has grown considerably over the past couple of decades, primarily due to modern innovations in lighting technology. And while traditional incandescents and fluorescents have enjoyed some of that technology boom, LED Lighting (Light-Emitting Diode) has come to dominate the industry and market for lighting products. LED is used for a number of applications, but many indoor growers are starting to put forth an effort to learn about LED technology, and rightfully so!
One of the first things to know is that almost all LED lighting solutions will require both a driver and a lamp in order to function properly. Smaller household applications, like LED screw-in lightbulbs for example, actually include an internal LED driver that satisfies this function. This is similar to how a CFL bulb includes an integrated ballast in its own screw-in bulb design.
Most LED light panels marketed for growing plants will have the driver included in the light’s assembly. This may be in a rectangular box attached to the outside of the panel’s case, or it may be concealed within the panel itself.
Best LED Drivers
Armacost Lighting – 60 watt Dimmable LED Driver with Removable AC Cord
200 watt Waterproof LED Driver – IP67 – 90V-130V AC to 12V DC Low Voltage Output with 3-Prong Plug – 3.3 Ft Cable
inShareplus 300W IP67 LED Driver – Waterproof Outdoor-Rated AC 110-260V to DC 12V 25A Low Voltage Transformer with 3-Prong Plug
Best LED Light Controllers
Titan Controls 8-Light Controller, 240V – Spartan Series
Hongruilite 4-Light – 4000W / 8-Light – 8000W – HID Master Relay Controller for Hydroponic Indoor Grow Lighting
LED Lamps, Drivers, and Arrays
A light-emitting diode works kind of like a traditional incandescent bulb, which runs the electric current through a filament and uses electrical resistance to make that filament grow hot and glow by consequence.
By comparison, instead of a filament, a diode takes advantage of a semiconductor’s p-n junction property and uses a gap more like an automotive spark plug.
When enough energy is put into the semiconductor, free electrons fill in the electron holes and the semiconductor becomes temporarily conductive. The leftover energy from the recombination of the free electrons with the electron holes is released as a burst of photons, or light particles.
The color of an LED lamp is determined by lengthening or shortening the gap, which translates into requiring more or less energy to “make the jump”.
Now, let’s take a moment to look at some of the jargon that is most commonly seen when looking at LED lighting.
To begin, the actual diode that emits the light and looks like a small whitish speck is referred to as an LED lamp. The circuit board, logic controller, or computer that regulates both incoming and outgoing electricity is the LED driver.
Because the lamp has no moving components and produces usable light without a filament or phosphorescent plasma, LED lamps are classified as solid-state lighting.
Individual LED diodes, even industrial-strength ones, tend to be quite small. Their small size and minimal demands for power allow one driver to run many lamps in a panel called an LED Array.
The panels seen in commercial greenhouse lighting systems are merely a larger array of light-emitting diode (LED) lamps, with the driver often being concealed within a case. Even larger are commercial and industrial LED lamps, which can consist of both larger, brighter diodes and a broader array of them.
Another way that LED lights stand out as superior to incandescent or CFL alternatives is that a single array, run by a single driver, can not only host hundreds of individual LED lamps, but can also mix up the colors to provide Full-Spectrum light.
There are even “smart” LED drivers that can be programmed by your cell phone, tablet, or laptop to do just about anything you can imagine a light doing!
This is all a huge innovative jump ahead from the Metal Halide (MH) and High-Pressure Sodium (HPS) cycle’s need for two separate lamps to fully satisfy most plants through both vegetative and blooming stages of growth. Indoor growers familiar with HPS/MH lighting know that you must use a special ballast to accommodate the lamp, and in a way, the LED driver serves the same function for its compatible lamp.
LED Output Types: Constant Current vs Constant Voltage
LED drivers are almost always going to be constant current devices. They are designed to deliver a constant amount of current, usually described as amps (A) or milliamps (mA). The vast majority of LED downlights used in indoor growing are constant current drivers.
However, LED lighting systems featuring integrated electronics that help control aspects of the lighting will almost certainly require a constant voltage driver instead.
This is an important distinction because most households and small businesses run on 120-277 Volt AC Current, which is Alternating Current. Sending 120V of alternating current directly to your diodes would almost certainly result in catastrophic failure of the array, possibly in a fire as well.
The LED driver takes the constantly fluctuating AC current and stabilizes its output into a constant state at a far lower intensity than what is coming in from the mainline.
Driver manufacturers accomplish this by using a proprietary design of circuitry that takes incoming electricity and regulates it down to the levels required to do the requested work. In this case, the work is the full illumination of a light diode, or an array of such diodes.
Most household-voltage LED light drivers use pulse-width modulation as a means of regulating voltage/current output to the lamp. This involves taking the incoming AC current and cutting it into “segments” that are then sequenced to emerge together in the form of a constant current at the newly determined output level.
This cutting and lining-up of segments of electricity is akin to creating resistance in the circuit, which will generate heat for as long as it is occurring. One major difference between LED lamps and incandescent bulbs is that an incandescent focuses resistance on the filament, while the LED focuses its heat into the LED driver.
Therefore, the designs of LED light drivers can be highly susceptible to thermal runaway, making the widespread use of a given driver and a study of consumer reviews an important part of choosing the best driver for your given application and lighting system.
Thermal Runaway occurs when current is delivered in excess of a driver’s maximum, resulting in high temperatures, shorter driver life, and potential system damage.
Put another way, when a light bulb “blows,” it is because the filament has endured the cycle of heating and cooling as far as the structure of the filament material will allow. When an LED light “blows,” it means the driver has either suffered the same fate as the filament, or was flawed from the start due to manufacturing defects, material quality, circuit design, etc.
Important Features to Consider in a LED Light Driver
This means that when you’re shopping for an LED light, the LED driver is one of the most important features you need to look at.
Of course, every grower has no shortage of other priorities in mind when they are doing their lighting homework. There are things like lumen output, coverage, and whether to take advantage of a grow tent’s reflectivity or not.
Let’s take a look at some of the driver-specific features that are available to choose from:
Dimmer Switch Technology
The most obvious difference between dimmable and non-dimmable lights is that the intensity of the former is easily adjusted through a specially-designed switch, while the latter puts out light at a fixed rate. This feature is inherent in the LED driver’s design. That being said, the ability to adjust the light’s brilliance and intensity can be desirable.
Unfortunately, much of the existing light-dimming technology has been developed around the function of incandescent bulbs that work by placing a load of resistance on a filament. This electrical resistance causes the filament to heat up rapidly, and within the vacuum of the bulb’s interior it glows brightly. As we explained above, LED works on a different principle of physics entirely, making some dimmer switches ineffective at controlling LED lights.
DALI, or a Digital Addressable Lighting Interface, is perhaps the most commonly seen method of providing dimming function to an LED array. DALI is a standardized communication protocol that is designed to provide power to lighting equipment and a higher degree of control to the consumer. DALI technology allows the indoor grower to make adjustments to the lighting system’s intensity with unparalleled precision – a feature that is not always available with other driver designs.
An analog variant on LED dimming technology is 0-10V Dimming. The 0-10V protocol generally relies on a console that routes voltage at varying strengths between 0V and 10V. Each channel has its own output node, and connecting the lamp to a given channel produces the given level of light intensity. This is an older technology that offers less precision, but the mechanical nature of analog generally makes such a device more reliable.
TRIAC Dimmers were designed with incandescent and halogen technologies in mind, and work by detecting the level of their resistive load and adjusting the current feed accordingly. The problem with using TRIAC tech on LED lighting systems is that LED doesn’t convey a resistive load to go on. Therefore, despite being a well-established technology in the global market, TRIAC dimming protocols are at risk of becoming obsolete.
A “smart driver” is simply an advanced LED driver that uses integrated electronics, such as a higher-level processor, to accomplish a multitude of new functions, the most important of which is the ability for a connected interface to communicate with the entire lighting system’s network. This interface can connect wirelessly or via cabled-connection, and can give the operator control over various aspects of light function, including:
– Brightness/intensity (dimming)
– On/Off Duration and Scheduling
– Temperature and driver health monitoring
– Electrical Usage and analysis
– Advanced Power-saving and Standby
– Pre-programmed and programmable array patterns
Ultimately, smart driver software is only limited by the creativity and ingenuity of the developers and programmers that design the apps and interfaces. Implementing microchip controllers into driver design creates an endless number of possibilities for precise control of the entire lighting system in unprecedented ways.
The initial costs of the smart driver technology can be high, however, regardless of their potential for saving money long-term.
So far, this has kept the technology on the commercial/industrial side, and only in high-end or luxury residences. In industrial applications, smart LED drivers can be attached to motion detectors that help automate lighting in warehouses and other logistical environments, for example.
An example of commercial smart LED driver implementation can be seen in the well-cited MIRAI Company’s indoor lettuce farms, often described as “the world’s largest indoor farm”. Mirai uses a total of 17,500 LED lights distributed across 18 separate cultivation racks that each go 15 levels high.
The miracle of Mirai was that the farm went from being over 1 billion yen in debt to 75.5 million yen in standing capital within the last 3 years. And while the turnaround isn’t entirely attributable to LED lighting or smart drivers, the COO, Mr. Nozawa, knew early on that LED technology would be vital to his plan for success.
By optimizing the LED lighting, adjusting the speed of the water flow in the hydroponic delivery system, and better regulating the air movements throughout the garden, Mr. Nozawa has set the bar high for indoor high-tech growers around the world.
Main LED Lighting Driver Applications
Another thing that indoor gardeners should keep in mind while they research LED lighting drivers is the multitude of applications for which LED technology is used. The notable increase to light intensity combined with enormous reductions in power draw when compared to any other lighting solution have led to virtually every industry looking into implementing LED technology into their infrastructure.
While the costs associated with retro-fitting or even installing new LED equipment can run higher for the initial purchase, most see this as an investment that pays for itself.
This is due to the savings associated with drastically lower power consumption, as well as the precision with which LED can be programmed to operate in accordance with other energy saving strategies.
There are specific lamps that are marketed as “grow lights” or “greenhouse lighting,” and may include highly salient features like waterproofing, choice of output spectrum, and built-in timers. There are other LED lights that may be marketed as something else entirely, such as a floodlight or whatever, that is of an appropriate spectrum to use in growing indoors.
What we’re saying is that there may be other commercial or industrial LED lighting systems that better meet your specific needs – especially in larger, more commercial growing environments. Give it due diligence in comparing it to other options that are specifically aimed at growing plants, just to be certain that the best choice is also an available one.
Principal LED Lighting Uses
– Residential (small garden, ambient lighting, etc)
– Commercial (office lighting, commercial greenhouse)
– Industrial (manufacturing, hydroponic farms, large-scale aquaponics)
– Commercial (signage, parking lots)
– Industrial (plants, factories, mining, diving)
– Public Safety (streetlights, traffic lights, etc)
Applications Benefiting the Most from LED Lighting
This last category is hardly meant to be an exhaustive list, but more of an example that illustrates some of the unique applications that have enjoyed substantial benefits from switching to LED technology.
– Indoor Horticulture and Gardening (residential, small-scale commercial)
– Commercial Agriculture (large-scale, commercial indoor farming)
– Event and Stage Lighting (concerts, theater, film, speeches, etc)
– Hospital, Surgical, and Clinical
– Forensic Discovery and Analysis
– Law Enforcement and First-Responders
– Accident Cleanup and Roadside Assistance
What does a driver do for LED lights?
An LED driver takes the incoming electrical voltage, usually 120V AC in the U.S., and uses resistance to both reduce the intensity and transition to constant current. This is most commonly achieved in modern LED drivers by way of pulse-width modulation. This breaks the incoming electrical current down into segments that are released in a sequence that delivers constant current at a lower intensity.
How do I choose an LED driver for my LED?
Choosing an LED grow light can be a daunting task; moreso when given proper due diligence, in fact. There are so many options available for purchase, and the bulk of the information on the subject is either biased marketing copy or dense technical discourse that is overflowing with jargon and scientific formulae.
You don’t need a PhD in Luminescent Engineering to pick a good LED light, fortunately, but there are a couple of things you should keep in mind.
First – A good LED grow light is rarely cheap, and a cheap LED grow light is rarely good.
Second – Right now, the mainstream LED lighting technology is relatively new to the market entirely, and so the market hasn’t been dominated yet by a small group of huge manufacturers with global monopoly.
For example, according to research by the Minnesota Pollution Control Agency (MPCA):
“Three manufacturers dominate the CFL market in the United States: General Electric, Osram Sylvania, and Philips Lighting.”
A quick Google search will reveal multiple lists for the “Top 20 LED Manufacturers” on the front page, providing a stark contrast between the LED and CFL markets. Incandescent is the original light bulb, and would be more entrenched than CFL, if anything.
So, how does all of this help you choose the right LED grow light?
Easy – the driver is the most common part to fail on a LED lighting system. Choosing a panel with a driver from a reliable manufacturer that already has an established reputation, particularly in the global market, is a smart first step. Even in the event that your driver might fail, larger companies with a stronger market presence like Meanwell or Sozen, are more likely to honor a warranty claim for a replacement unit.
Smaller manufacturers inherently have less overhead in their business, and therefore a presumably lower bottom line. This can translate into lower purchase price, in many cases. But there are a few things to consider if you choose to work with a global or international vendor:
– Test the language barrier early, ideally before you spend money. Many foreign vendors are accustomed to negotiating, even to the point that they can be confused or suspicious of you when you accept their asking price without question.
– Lower overhead and bottom line can also mean less capital, and therefore less or even no ability to absorb returns, shipping costs, etc. Often, a closer look reveals a low sticker-price with a packaging/shipping fee that brings it parallel to the big company’s (or higher).
– LED Drivers burn out quicker when they are assembled poorly, fabricated from low-quality components materials, or their labels are not an accurate measure of their ability to regulate electrical current. Ask outright who manufactures the driver on a given LED Array (it doesn’t have to be the same company), and avoid anyone with vague or deflective responses that is reluctant to give you a company you can lookup.
Do you need a driver for LED downlights?
LED Downlights, also commonly called can lights, are most often sold in packs of multiple lights that are connected by a junction box. The junction box includes the LED driver equipment for distributing power to all of the included lights, and the better ones will include a dimming control as well.
Ensenior 12 Pack 6” Ultra-Thin LED Recessed Ceiling Downlight with Junction Box, 4000K Cool White, 12W 110W Eqv, Dimmable Can-Killer Downlight, 1050LM High Brightness
How long does an LED driver last?
According to Lighting Manufacturer,
“…the electrolytic capacitor is usually the component with the lowest reliability in the drive circuits. Electrolytic capacitors are susceptible to failure…”
The electrolytic capacitor is an internal component of the driver, and is vulnerable to the constant release of energy in the form of heat. While LED lights don’t project the same kind of heat from the bulb, the way incandescents do, they do generate heat in the driver.
This susceptibility for failure from heat in the driver is important to keep in mind, because the life of the diode may be 50,000 or even 100,000 hours, while the driver may be rated for 25,000 hours or less. Deceptive marketing can boast one number and omit the other, making a careful consideration of your light’s LED driver that much more important.
Do LED drivers get hot?
If you’ve spent just 3 minutes looking into LED drivers, the name MEANWELL has likely come up. They are considered to be one of the most reliable LED drivers in the game, and they say straight up that heat is one of the biggest causes of failure in any LED driver.
As the driver unit works, it will generate heat. As that heat accumulates, it has a direct impact on how much power you are able to send to the unit without damaging it. This impact is called the derating curve, and at the high-end of the operating temperature range you can only operate at 50% of the rated output.
As you can see, getting your head wrapped around LED drivers and the way they work is kind of important.
Where do I mount my LED driver?
Most LED downlights, such as the kind commonly used for indoor growing, come with a driver attached to the array. The only kinds of LED grow lighting that you will need to worry about purchasing or wiring in drivers for are DIY kits and rope/string lights, unless you are looking into replacing a damaged one. You should be aware that internal circuitry between the driver and the diode can be delicate, and more could be damaged than you first realize.
However, we’re the type to try and replace it, too. So we got you.
An LED downlight for growing can attach the driver to the array a number of ways, with the determining factor usually being the brand’s design theme or whatever is cheaper to fabricate. Some drivers are integrated internally, allowing for a slim panel design. Others are often mounted on top of the light, between the power cord and the array panel itself.
Consider the Spider Farmer SF-2000 2’x4’ LED grow light for a moment. The driver is mounted centrally on the backside of the panel, and includes ports for daisy-chaining and a manual dimmer knob.
In conclusion, one thing becomes crystal clear. LED lighting is a fairly complex technology that likely has a future ahead of it that is even brighter than the light being poured out for millions of plants around the world to thrive on.
As hobbyists, botanists, and farmers continue to get this new tech dialed in to be copacetic with their garden’s individual needs, we will continue to see record-breaking plants from every species. This will reset the standard on what we expect from our flora, and we have no doubts that humanity will carry on to raise the bar ever higher.
Best of luck as you work towards doing the same in your own garden, whether it be a modest arrangement or an all-out farm. The future is here, and we couldn’t be more proud to share it with you all.
Thanks for reading!