LED lighting: What new components are needed in the new trend?

Taking stock of the air vent industry around us, LED lighting will definitely not be absent. According to research data from TrendForce Consulting, the global LED lighting market will reach $78.36 billion by 2026, maintaining a compound annual growth rate of 3.9% from 2021 to 2026.

If we further explore the segmented market of LED lighting, we will find that in addition to continuing to increase penetration in indoor lighting fields such as home and building, LED lighting has also shown strong growth momentum in some outdoor and professional lighting fields, among which LED street lighting is a typical application scenario.

The innate advantages of LED street lighting

Traditional street lighting typically uses high-pressure sodium lamps (HPS) or mercury vapor lamps (MH), and the technology is already very mature. However, compared to these two, LED lighting has many inherent advantages.

Low energy consumption

Research data shows that in a city, street light energy consumption usually accounts for about 30% of the municipal energy budget, and the low energy consumption characteristics of LED lighting can precisely reduce the burden of this high energy expenditure. According to calculations, switching to LED street lights globally will reduce global carbon dioxide emissions by millions of tons.

Good directionality

The traditional road lighting source lacks directionality. On the one hand, this will lead to insufficient lighting brightness in key areas. On the other hand, because the light scatters to areas that do not need illumination, it will also cause light pollution. The excellent directionality of LED lights can overcome this problem by illuminating limited spaces without affecting the surrounding area.

High light efficiency

ompared to high-pressure sodium or mercury vapor bulbs, LED light sources have higher light efficiency, which means that unit power consumption can generate higher lumens. Moreover, the infrared (IR) and ultraviolet (UV) light content of LEDs is much lower than other traditional light sources, which means that they generate less waste heat and the thermal stress on the entire lamp is much smaller.

Long lifespan

As is well known, LED has a high working junction and an ultra long lifespan. According to calculations, the service life of LED lighting arrays in road lighting can reach 50000 hours or more, which is 2-4 times that of high-pressure sodium lamps or metal halide lamps. The savings in related materials and maintenance costs brought about by the lack of frequent replacement are impressive.

More environmentally friendly

Due to the presence of toxic substances such as mercury, high-pressure sodium lamps and mercury vapor lamps require specialized treatment procedures when discarded, which is time-consuming, labor-intensive, and not environmentally friendly; Moreover, metal halide lamps may also explode in certain situations. LED lighting fixtures, on the other hand, do not have these issues and are more environmentally friendly and safe to use.

Strong controllability

The driving method of LED street lights is to convert power sources such as AC/DC and DC/DC to provide the required voltage and current for the LED. Although this increases the complexity of the circuit, compared to traditional AC lighting technology, it has better controllability, faster response speed, and can achieve fast switching and dimming. Moreover, LED color temperature can also be accurately controlled through component selection. The improvement of controllability is a key element required for automated intelligent lighting, so LED street lights have become an indispensable item in the list of smart city construction.

Two major trends in LED street lighting

Due to the outstanding advantages mentioned above, the large-scale application of LED lighting in urban road lighting has become a trend. However, it is worth noting that this technological upgrade is not a simple "replacement" of traditional lighting devices, but a systematic transformation. In this process of change, there are two trends that are worth paying attention to.

One trend is intelligence. As mentioned earlier, LED lights have stronger controllability, making it possible to build an automated intelligent street light system around them. Such a streetlight system can automatically adjust the switch and brightness of streetlights based on environmental information (such as ambient light, the presence and movement of human bodies or objects) and precise algorithms or even machine learning capabilities, without the need for manual intervention. The benefits brought by this are obvious. Moreover, as an infrastructure network covering the city, street lights themselves have the potential to become a more intelligent edge node of the Internet of Things. In the future, LED street lights are likely to add more functions (such as meteorological and air quality monitoring), making them play a more important role in smart cities.

However, we can also imagine that this intelligent trend will bring new challenges to the design of LED street lights, that is, the system will become increasingly complex. This means that within the limited exterior space of street lighting, it is necessary to include lighting, driving, sensing, control, communication, and more extended functions. To address this challenge, standardization is a necessary path, which is also another important trend in the development of LED street lighting. The benefit of standardization is that it allows more technology suppliers' functional modules to seamlessly integrate into LED street lights, greatly enhancing the scalability of the system.

Intelligence has given rise to the development of standardization, which in turn has led to the deepening of intelligence - these two major trends interact and jointly promote the evolution of LED street lighting technology and applications.

The Evolution of LED Street Lamp Architecture

The results of this technological and application evolution can be seen from the evolution of LED street light architecture.

The standardization of street lighting has long existed, and the most familiar one is the ANSI C136 standard widely used in many parts of the world. Many street lights are produced based on this standard today.

The initial streetlights used traditional lighting fixtures, with a very simple control logic - turning them off during the day and on at night, which only required a photodiode (photo controller) to achieve. In order to achieve interchangeability of control units, the ANSI C136.10 standard defines a universal platform for regional lighting equipment, which can standardize sockets for optical controllers based on AC line voltage and 3-pole connection. The standard interface developed based on ANSI C136.10 has gradually become a de facto standard in the industry (as shown in Figure 1).

Figure 1: Architecture of ANSI C136.10 non dimmable 3-pole light controller

However, you may have noticed that the ANSI C136.10 standard can only meet the control architecture of non dimmable 3-pole light controllers. With the application of LED technology in street lights, the demand for adjustable lighting functions with higher energy efficiency is also growing, which requires new standards and architectures to fill the gap. This new standard is ANSI C136.41. The ANSI C136.41 architecture adds signal output contacts on the basis of a 3-pole line voltage connection, which can connect the power grid to the ANSI C136.41 optical control system and switch the power to an LED driver; The internal power supply unit (PSU) converts the power grid into a logical voltage, and controls the system power supply through signal output lines to achieve control and regulation of LED lighting fixtures (as shown in Figure 2). Moreover, this standard is backward compatible with existing lighting systems and supports wireless communication, providing an economical and reliable intelligent street light solution.

Figure 2: ANSI C136.41 Adjustable Light Controller Architecture

However, the ANSI C136.41 standard is not perfect, as it does not support input of sensor information, which limits the implementation of more automated street lighting systems. To this end, the global lighting industry alliance Zhaga has launched the Zhaga Book 18 standard specifically designed for outdoor lighting, which introduces the D4i protocol of DALI-2 to solve the design of communication buses in lighting systems and solve the wiring problems that plague developers. A significant difference between the Zhaga Book 18 standard and ANSI C136.41 is that the PSU is no longer integrated into the optical controller component, but rather integrated into the lamp as a part or separate component of the LED driver. This architecture simplifies the wiring of lighting fixture control nodes and supports a new "dual node architecture", that is, in the street light system, an upward connected node device acts as a phototube control or communication node, and another downward connected node can be used for downward viewing operation or other types of sensors (as shown in Figure 3). In this way, a complete intelligent street light system is basically formed, and the expansion of its control, communication, sensing and other functions can be easily achieved by connecting standardized modules.

Figure 3: Zhaga Book 18 Dual Node Architecture

It is worth noting that the dual node architecture of the Zhaga Book 18 is not the endpoint of the evolution of LED street lighting architecture. In recent years, a "hybrid dual node architecture" has emerged that integrates the advantages of ANSI C136.41, as well as the convenience and open architecture of the Zhaga-D4i. In short, a hybrid dual node architecture with upward node devices is an optical or communication node connected by a 7-pole ANSI C136.41 interface (without switching the power grid to an LED driver), which can power the ANSI C136.41 node from auxiliary PSUs, internal/external drives, or DALI buses; The downward node still serves as a sensor input device and is connected through the Zhaga Book 18 interface (as shown in Figure 4). The streetlight system based on this architecture further simplifies wiring and can fully utilize the ecological resources of ANSI and Zhaga standards.

Figure 4: Zhaga/ANSI hybrid dual node architecture

It is obvious that with the evolution of LED street lighting architecture, the technical options available to developers have become more diverse. People can choose the most suitable architecture based on actual design needs to achieve the upgrading of street lighting systems. Moreover, thanks to the advancement of standardization, LED lighting components and functional components that comply with ANSI or Zhaga standards are becoming increasingly abundant on the market, which will make the intelligent journey of LED street lighting systems smoother.

TE's solution

TE Connectivity (TE) has always had a comprehensive and in-depth layout in the field of LED outdoor and professional lighting. Based on the evolution of technology, it continuously introduces innovative products and solutions that meet industry standards. Today we will introduce several star products worth planting grass for everyone.

LUMAWISE Endurance N+control base and protective cover

TE's LUMAWISE Endurance N+control base and protective cover are networked lighting control accessories that comply with ANSI C136 standards (ANSI C136.10/C136.41). They provide power and signal interfaces between lighting control and lamp installation sockets, and can provide protection for node equipment under harsh conditions - a crucial feature for street lighting systems - whether designing ANSI C136 single node or hybrid dual node systems.

The base assembly comprises a power supply twist lock terminal, a reed signal terminal and an integrated sealing gasket, which can achieve the sealing level of IP66 and prevent the invasion of dust and re spraying spray; The translucent protective cover can let sunlight transmit to the light sensing device; The design of integrating ventilation holes into base components can extend the expected life of electronic components inside the casing; At the same time, its protective cover meets the UL94 5-VA flammability level, which ensures the long-term reliability and safety of power and signal interfaces as well as internal electronic components.

Figure 5: LUMAWISE Endurance N+Control Base and Protective Cover

LUMAWISE Motion Street Lighting Motion Sensor

In addition to providing interconnecting components in LED street lighting, TE can also provide complete node device solutions, such as LUMAWISE Motion street lighting motion sensors. This sensor can perform dimming control of LED lighting fixtures based on the movement of human beings or objects detected within a designated area.

LUMAWISE Motion has passed the Zhaga-D4i certification, which means it can be applied to any system that meets the Zhaga-D4i standard. It can be used as an independent control device, or it can be used together with Zhaga-D4i phototube or communication node to improve the control level. In addition, the accompanying shield can be used to create custom detection areas.

This sensor is equipped with a standard Zhaga book 18 interface and is suitable for dual node LED street lighting systems. It can easily connect lights from below without the need for special tools with one hand. It is a comprehensive and user-friendly sensor component.

Figure 6: LUMAWISE Motion Street Lighting Motion Sensor

NECTOR T Pluggable Lighting Connector System

Outdoor LED lighting system wiring also requires special requirements for line to line connectors, with the core two points being the reliability of interconnection and the convenience of operation.

TE's NECTOR T pluggable lighting connector has an IP68 sealing rating, making it less susceptible to UV (sunlight), rain, and dust when used outdoors. It also provides protection for the plug-in interface when not plugged in (open circuit), making it very suitable for applications in high humidity and harsh environments, such as road lighting, landscape lighting, gardening lighting, etc.

In terms of ease of use, the connector adopts crimping and screw terminals, which are fast and flexible to install, and can be easily installed and repaired using standard tools; And it supports pre terminated cables, which can reduce labor and installation costs. NECTOR T connectors provide a complete product range, including three-way and four-way splitters, connectors, and panel mounted connectors, to meet diverse wiring interconnection needs.

Figure 7: Connector T Pluggable Lighting Connector System

Summary of this article

LED lighting fixtures, due to their low energy consumption, good directionality, long lifespan, fast response, pollution-free, and strong controllability, are rapidly penetrating into various aspects of the lighting field (such as indoor and outdoor lighting), and are also unlocking more creative new applications (such as agricultural and horticultural lighting). In this process, the two major trends of intelligence and standardization are jointly driving the rapid evolution of technology and applications, as well as driving innovation in system architecture and basic components.