Indoor horticulture is becoming the future of agriculture faster than anyone ever imagined. The world population is growing while available land for farming is decreasing, creating the need for more sophisticated indoor food production methods. The lighting system is perhaps the most expensive and critical part of a successfully controlled agriculture environment (CEA). Deciding which technology to use is therefore very important.
Indoor horticulture has been around for some years by way of greenhouses. This method allowed for some control of the growing season but still relied heavily on the sun, making it difficult to implement in areas of the globe with minimal sunlight.
Hydroponic Grow Lights
As lighting technologies improved, so did indoor horticulture. The greenhouse became the staple for hobbyists while commercial growers began to experiment with large-scale indoor food production and horticulture.
At first, growers used fluorescent tube lights to grow herbs and vegetables indoors. But the fluorescent tubes were not rugged enough for commercial applications and required frequent replacing. Compact fluorescent lights (CFL) offered an improvement to the tubes as they use less energy and emit minimal heat, thereby allowing farmers to grow more plants in less space. But just like the incandescent light that preceded fluorescent and CFL technology, growers had minimal control over the systems.
High-pressure sodium (HPS) lights became the choice for most commercial indoor growers as they viewed the technology as established and dependable. However, HPS lighting systems require a substantial investment and produce a lot of heat. This means that plants must be kept at a safe distance.
LED system manufacturers looked for ways to fill the void in the horticultural lighting industry by designing technology that is more rugged, lasts longer, and gives growers greater control over the growing environment.
There are many advantages to using LED grow lights over the other available technologies. The primary benefit is lower energy costs, as much as 70 percent over the more traditional lighting technologies. LEDs also last on average 10 years as opposed to the traditional grow lights. This means a significant reduction in overall costs as frequent replacements cost time and money.
Lights like these can last up to 10 years
Last, but not least, LED grow lights give growers complete control in specifying the wavelengths of light that reach their plants. Blue and red colors tend to be ideal for the majority of plants. This is why horticultural lighting tends to be purple as growers can select just the right amount of blue and red to create ideal growing conditions. Furthermore, the system can be programmed to provide more lighting at night when energy costs are lowest, making this the most energy-efficient grow lighting system available.
Of course, an LED grow lighting system is only as good as the LED driver and other essential components that serve as the backbone of this technology. At GRE Alpha, we pride ourselves at producing the most advanced and dependable powering and lighting control solutions for horticultural and grow lighting applications.
Our LED powering solutions are ideal for indoor horticulture as they are both robust and flexible. Our lighting control modules can also be added to enable complete color tuning. Our XLD and SLD Series of dual-mode, easy to install AC/DC LED drivers fit perfectly in any indoor agricultural environment. Our SLD-DIMTW tunable white dimming module enables smooth and dynamic color temperature shifts of 2000K to 8000K, allowing growers complete control of the lighting in their growing environments.
XLD and SLD series Easy Install (left) and SLD DIM TW tunable white (right)
While some may be discouraged by the initial investment, when all is factored in, LED grow lights offer far superior light quality, longevity, and return on investment than any other grow lighting systems available on the market.
About GRE Alpha
GRE Alpha® Electronics, Ltd. specializes in the design and manufacture of solid-state lighting power supplies and lighting control accessories which are the lifeblood of indoor and outdoor LED lighting systems. Unlike many in the LED industry, GRE Alpha focuses on a modular approach. Their products can be used either in conjunction with existing systems or with new setups.
With more than two decades of power conversion expertise and a commitment toward innovation, GRE Alpha engages with industry pioneers to deliver highly efficient, installation-ready and agency-approved LED power conversion products for a wide variety of industry applications.
Lighting designers have been working for decades to bring intelligent automation and control to architectural and industrial lighting systems. The international adoption of the Digital Addressable Lighting Interface (DALI) in 2000 was a major step forward in this effort. DALI enables the creation and integration of scalable and smart lighting systems into intelligent networks and the Internet of Things (IoT) by standardizing the way in which components and power supplies used for IoT lighting exchange diagnostics, command, and measurement data. DALI and IoT offer designers a robust, reliable, and cost-effective protocol for creating smart next-generation lighting systems.
As part of its effort to deliver the best LED power supplies and modules for smart lighting systems, GRE Alpha works as an active partner of the global DALI alliance to bring the benefits of DALI-certified dimming modules to lighting designers. This article explains and outlines the benefits for lighting designers of using DALI dimmers and power supplies used for smart lighting for lighting solutions connected to the Internet of Things.
Digital Addressable Lighting Interface (DALI) is an open protocol defined by the international standard IEC 62386 and IEC 60929. When first drafted in 2000, DALI brought lighting within the realm of digital control by enabling two-way digital communications with dimmable ballasts, transformers, relay modules and other components. Since the DALI standard was established industry wide, DALI-certified components from multiple manufacturers were compatible with each other. Components are certified as compliant with the DALI standard by the Digital Illumination Interface Alliance (DiiA), an open consortium of companies that helps to standardize and promote DALI-based lighting solutions.
DALI dimming modules, ballasts, and other components make up a simple two-wire network of up to 64 individually-addressable components that can be controlled and monitored using standard commands and protocols. The protocol is compatible with the operation of a wide variety of lighting systems including LED, fluorescent, HID, and halogen. DALI devices can be programmed individually or in groups to enable a high degree of flexibility because lighting systems can, in many cases, be reconfigured in software, without the need for rewiring.
DALI also allows two-way communication, which means devices can report a failure or respond to a status query. Devices can be configured to turn on and off, dim from 0-100%, and remember power-on levels, dimming levels, maximum levels, fade rates, and fade time. Two-way data transfer and power are delivered on the same pair of wires, so no separate bus cables are needed.
Since the DALI protocol was established, components from many manufacturers have been certified as compliant with the IEC 62386 standard. Two of GRE Alpha’s DALI dimmers, for example, which were on display at the ERG Lighting booth at Lightfair International 2018 in Chicago. The GRE Alpha SLD-DIM DALI dimming module provides flexibility and ease of use for smart home lighting automation projects, while the GLD-DIM, which has an available DALI version, is a compact dimming module that serves as an add-on for constant voltage LED drivers. Both modules are fully compatible with LED power supplies used for IoT lighting. The Internet of Things was a key topic in workshops, product announcements, and networking events at Lightfair 2018.
SLD-DIM DALI Dimming Module by GRE Alpha
Introduced in late 2014, the updated DALI-2 standard, formally known as version 2 of IEC 62386 standard, is another important step towards connecting lighting systems to the Internet of Things. The updated standard was restructured to make it easier to use and fill in the gaps in the original standard. DALI-2 adds new features and commands and introduces standardization of control devices and the addition of input devices, while maintaining backwards compatibility with the original standard.
The most significant change in DALI-2 is the addition of control devices including application controllers and input devices that were not included in the original standard. Application controllers are intelligent controllers that take information from input devices or other controllers and make decisions and send commands. They can operate as single masters or multi masters. Input devices, on the other hand, are simpler and include push-button switches, sliders, and sensors. They’re used in event-driven mode and provide information to the system.
Other improvements of DALI-2 include:
DALI-2 also allows an additional 64 addresses for devices such as keypads or sensors. With a total of 128 addresses on a single DALI-2 network, more flexible lighting systems can be built with less complexity and cost. The standardized DALI data model specifies the format and content of measurement and diagnostic data and the location of data in the DALI driver. This allows for seamless information exchange between products such as DALI dimmers, drivers, and other components.
DiiA continues to introduce further enhancements to extend the DALI lighting protocol to enable new possibilities for lighting designers in the age of IoT. For example, DiiA is developing a specification for DALI drivers to power sensors and communications devices within luminaires, and to establish a network inside a luminaire. Other changes will enable intelligent lighting fixtures to communicate with the IoT with DALI-enabled nodes and to allow luminaires to be upgraded to the latest IoT technology. For LED lighting systems, new additions to the DALI-2 standard will also offer support for color control (RGB and temperature) and allow better reporting of energy usage and LED temperature.
As with the original DALI standard, lighting equipment manufacturers must go through a rigorous process for each product to achieve DALI-2 certification. The process is managed and operated by the Digital Illumination Interface Alliance (DiiA). Only DiiA-certified products can carry the DALI and DALI-2 logo, and only DiiA members can certify their products.
DALI 2 standard will introduce controllers to various devices such as these bulbs
When selecting the best LED power supply and dimming modules, lighting designers and architects should keep in mind the many advantages of the standardized DALI protocol. DALI and DALI-2 certified lighting components offer a robust, reliable, and cost-effective approach for creating lighting systems that are more easily integrated into the IoT. By standardizing measurement and control data and protocols, DALI dimming modules and LED power supplies used for IoT lighting offer benefits such as ease of installation, flexible design, and interoperability.
GRE Alpha is a member of DiiA and continually works within the alliance to develop DALI dimmers and other LED lighting components to enable advanced IoT lighting systems.
More than 200 years ago, Henry Joseph Round observed that carborundum (SiC) crystals emitted a visible yellowish light when a potential of 10V was applied. He also observed that different crystals would emit green, orange, or blue light. In a letter to the editor of The Electrical World’s February 9, 1907 edition, he requested that any other person investigating this phenomenon contact him. That was unlikely to happen because Round was the first person to document this “ curious phenomenon” as he called it. His discovery of electroluminescence paved the way for today’s LEDs.
However, the first LEDs had low luminous efficacies, and as such, they were only useful as control lamps. They also tended to flicker if not supplied with a constant energy source. The development of LED drivers to convert mains voltages to match the load requirements for luminaires, meant greater stability, which coupled with increased efficiency and durability, make today’s LEDs real contenders in any lighting application.
At GRE Alpha, we take great pride in developing and manufacturing the best quality LED drivers. LED driver selection can be confusing to even the most experienced lighting system designer. The steps below should help guide you in selecting the most appropriate LED driver for your application.
Our voltage drop calculator can assist you in selecting the right product for your application.
GRE Alpha® Electronics, Ltd. specializes in the design and manufacture of solid-state lighting power supplies and lighting control accessories which are the lifeblood of indoor and outdoor LED lighting systems. Please visit our website www.GREAlpha.com to learn more about our great selection of drivers.
LED technology offers many advantages to designers of architectural lighting systems. LEDs are more energy efficient, offer a lower overall cost of operation, and provide the potential for eye-catching aesthetics and innovative design. The features and specifications of LED lighting fixtures themselves are important, but the choice of architectural LED power supplies (or drivers) is also critical. Let’s look at five ways architectural LED drivers affect the design and performance of LED lighting systems.
LED drivers take AC current from the mains and convert it to low-voltage DC current required by the LEDs themselves. Like any complex electrical component, drivers must be installed by qualified technicians, which means that ease of installation is a key factor in reducing the cost of deployment. Devices like GRE Alpha’s Easy Install drivers, for example, incorporate features like integral wiring compartments to reduce installation time and eliminate the need for additional components during the installation process. These drivers are also user configurable to constant-current or constant-voltage output, which offers design flexibility while minimizing tracking of extra SKUs.
Reliability is a key factor in reducing down time of LED lighting systems. The LEDs themselves, if used properly, last far longer than incandescent or neon lights, so LED drivers should have a correspondingly long lifetime. The mean time between failure (MTBF), a measure of the reliability of a high-quality LED driver, helps in estimating operating costs of an architectural lighting project at the design stage. Typical MTBFs of LED drivers range from 50,000 hours to 500,000 hours under normal operating conditions.
LED drivers must also exhibit sufficient ruggedness to protect against voltage surges. Like most electronics, LEDs are sensitive to such surges and to accidental electrostatic discharge during handling. Some LED drivers are designed to withstand surges of several thousand volts. In applications such as outdoor signage where lightning strikes are a problem, optional surge protectors that protect the drivers themselves are advisable.
LED drivers and dimming modules enable fast and flicker-free control of LED intensity from 0-100%. Dimming LEDs with manual switches lends itself to energy efficiency, of course. But modern lighting systems require a greater level of control, especially through integration with smart building systems that can be monitored and controlled over intelligent networks to optimize lighting quality and minimize energy consumption.
For example, intelligent control and monitoring of LED lighting systems can make it possible to collect information about how lighting is used in each room or section of a building to help optimize energy consumption over time. Eventually, lighting might even be optimized for a person based on preferences stored on their smartphone, or for a particular meeting room based on how many people are present.
To enable intelligent lighting control, or to future-proof a lighting system, it’s essential to deploy high-quality LED drivers that can integrate with dimming modules with industry standard DALI (Digital Addressable Lighting Interface) or DMX.
In the hands of a creative designer, LEDs offer the potential for the attractive and dynamic lighting of signage and building exteriors and interiors. Their fast response and controllability offer a relatively inexpensive way to freshen the appearance of both the interior and exterior of older buildings without extensive renovation.
In some cases, architectural lighting systems are deployed in stages with LED strips, so it helps to have power supplies used for LED strips that enable scalability. Constant voltage architectural LED drivers offer the flexibility to add LED lighting strips without replacing the drivers themselves. For example, GRE Alpha’s constant voltage Signage-Pro driver offers maximum flexibility and robustness for exterior architectural lighting. This driver features user-adjustable voltage, output for cooling fan control, and a heavy-duty design for use in exterior applications.
Many architectural lighting applications require a high quality of light, over and above brightness, which includes a minimization of flicker and control of the temperature of the light. These are all a function of the LED driver which must take AC line current, sometimes of unpredictable quality and stability, and convert it to steady and clean direct current without ripple to ensure a light that’s pleasing to the eye.
Some drivers can also help LED light appear more natural. The GRE Alpha Tunable White SLD-DimTW, for example, can change light from a warm to cool temperature as a function of brightness. This mimics natural light as it progresses from the soft warm light of sunrise to brighter and cooler mid-day light.
LED technology offers many advantages to designers of architectural lighting systems including energy efficiency, scalability, and light quality. Since they are inherently electronic devices, LEDs require high quality drivers to operate, and the choice of drivers is critical for optimum lighting design and performance. The most important features of architectural LED drivers include installation cost, reliability, and scalability, as well as control of light quality and integration into smart building systems.
The LED has come a long way since its invention more than 50 years ago. From instrumentation indicators to digital clocks to holiday displays and more recently smart buildings, the application options for LEDs seem limitless. As environmental awareness increases, more consumers look to benefit from the energy efficiency and durability of LED lighting systems.
LED street light
Municipalities also increasingly look to tap into these benefits by replacing dated energy-guzzling streetlights with more efficient LED street lighting. Manufacturers responded to the demand by forming partnerships and developing the LED technology to meet the more rigorous standards for street lights. Along with decisions about illumination, color, intensity, connectivity and ingress protection, the most important consideration for a street lighting retrofit must be the driver which supplies the power and controller to the LED. So what are some key factors to consider when choosing an LED driver for a street lighting system?
LED streetlights must be durable as well as easy to maintain. More and more manufacturers are responding to this demand by designing systems with remote LED drivers that reside in the junction box at the base of the streetlight instead of inside the fixture at the top of the pole. This allows for easier maintenance as the driver tends to be more prone to failure than the LED. Easier maintenance means added savings to municipalities.
Remote drivers also play a role in LED thermal management. LED drivers are traditionally built into LED fixtures on the head in front of the LED module. During the voltage conversion process, LED drivers produce thermal energy which gets trapped in the housing and transferred to the LED. High temperatures lead to premature failure. LED fixtures with remote drivers are exposed to less heat and are therefore more durable than their built-in counterparts.
Multiple LED street light installation
LEDs operate at low voltages and are more sensitive to overvoltage than traditional bulbs. Standard LED drivers are designed to withstand overvoltages from 2kV to 4kV, but streetlights are subjected to much higher degrees of voltage fluctuations. Power grid overvoltages, for example, can reach as high as 6kV while lightning strikes are known to generate overvoltages as high as 10kV. Electrostatic discharge (ESD) generated during routine maintenance can also impact unprotected LEDs.
High overvoltages can cause high currents and the premature aging of LEDs, leading to reduced service life and decreased economic benefit to municipalities. Designers must, therefore, consider adding a quality surge protector aptly rated for the intended application environment.
If future expandability is critical, then controller capabilities must also be a consideration. Digital Addressable Lighting Interface or DALI-based controllers are becoming increasingly popular for street lighting control. Not only because they can be upgraded to wireless, but also because these controllers offer greater compatibility with existing lighting control systems. DALI controllers are simple, scalable, flexible and robust. DALI can control individual LEDs or even groups of LEDs and are easily reconfigurable for changing conditions.
Rapidly evolving LED technology has opened the door to new applications in public street lighting as cities worldwide seek to reduce costs and improve night visibility. The complexities of municipal street lighting require that designers consider many factors when specifying a conversion, chief among which are LED driver attributes. The most effective drivers are easy to maintain, offer surge protection, lighting control and ensure LED longevity.
Bullough, J. D., Lighting Research Center., New York State Energy Research and Development Authority., & New York (State). (2012). Guide for optimizing the effectiveness and efficiency of roadway lighting. Troy, Ny.: Lighting Research Center.
Drivers enable next-gen LED street lighting. (January 01, 2012). Electronic Products New York-, 54, 12, 44.
Signorino, I. (May 01, 2012). Drivers enable next-gen LED street lighting: What designers must consider when selecting a driver, focusing on why eliminating the step-down transformer is a good idea. Electronic Products, 54, 5.)