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10 Important Facts That You Should Know About Led Street Light

10 Important Facts That You Should Know About Led Street Light

10 Important Facts That You Should Know About Led Street Light


1. What is LED street light?

LED street lamp refers to the street lamp made of an LED light source, which has the unique advantages of high efficiency, safety, energy-saving, environmental protection, long life, fast response speed, and high color rendering index, which is of great significance to the energy saving of urban lighting.

Road lighting is an important part of urban lighting. Traditional street lamps are often used. High-pressure sodium lamps emit light at 360 degrees. The shortcomings of large light loss cause a huge waste of energy. LED street lights have gradually entered people's field of vision with the advantages of directional light emission, low power consumption, good driving characteristics, fast response speed, high shock resistance, long service life, green environmental protection, etc. Therefore, LED street lights will become the best choice for energy-saving renovation of road lighting.

LED street lights based on 901 milliwatt output LEDs can typically produce the same (or higher) brightness as conventional lamps, but require only half the power consumption. LED illumination usually does not fail, but lowers the output until it needs to be replaced.

2. What are the types of LED street lights?

According to different shell designs, LED street lights can be divided into modular street lights and full die-casting street lights.

2.1 what is a modular design LED street light?

As the name implies, the modular street light adopts the LED modular design. The LED module can be disassembled freely without destroying the lamp body. Generally, plug-in waterproof connectors are used. The module power can range from 30-60w, such as 200W SA street lights, it can be done with 4 modules or 5 modules, the power matching is flexible, and the plug-in design at the same time, the replacement and maintenance of the modules in the future is very simple.

10 Important Facts That You Should Know About Led Street Light

Figure 1: Modular design

2.2 What is a full die casting street light?

Full die-cast street light means that all parts of the lamp housing are made of die-casting. The radiator is integrated with the lamp housing, and the LED light-emitting component is a single piece, which is fixed on the lamp body together with the optical lens by screws. If you want to replace the LED, Only the whole light board can be replaced, and the maintenance cost will be much higher than that of the modular street lights. For example, our SB, SE, SC, SD, SG, SI street lights all adopt the full die-casting design. I believe that the full die-casting street lights are the future. The mainstream direction of street lamp design.

10 Important Facts That You Should Know About Led Street Light

Figure 2: Die-casting design


2.3 Video of SE Street Light

2.4 Download

Installation Manual_StreetLight_SE.pdf

Specification_SE_LED Street Light.pdf

3. What are the main applications of LED street lights?

As the main luminaires of urban road lighting, LED street lamps are widely used in places including urban streets, roads, country trails, parking lots, parks, shopping malls, highways, etc. 

The following are some projects cases sharing of MKLIGHTS road lighting:

10 Important Facts That You Should Know About Led Street Light

10 Important Facts That You Should Know About Led Street Light

10 Important Facts That You Should Know About Led Street Light

200W LED Street Light in City Road90w LED street light in country trails135W LED Street Light in Residential road

10 Important Facts That You Should Know About Led Street Light

10 Important Facts That You Should Know About Led Street Light

10 Important Facts That You Should Know About Led Street Light

55W LED Street Light in parks60W LED Street Light for solar system40-60W LED Street Light in Parking Lot

4. What is the difference between LED street lights and HPS street lights?

Street lighting is the lamp with the longest use time and the largest power consumption. The use of LED light sources for street lighting will greatly reduce the shortage of electric energy in the city and save the country's energy. The following is the performance comparison of LED street lamps and HPS lamps.

4.1 Service life comparison

The HPS circulating in the market today have short lifespans due to quality and technical problems, generally less than 6,000 hours. The lifespan of LED street lamps is more than 100,000 hours, which is equal to more than 16 times the lifespan of HPS lamps. The cost of replacing the light source, maintenance costs, and the inconveniences caused by them are the most obvious comparisons. LED street light has no effect on the number of switches, unlimited, while the HPS lamp has a certain limit on the number of switches, generally only 4000 to 5000 times, and the life is over. The LED street light has no blackening phenomenon at any number of times of switching and the end of its service life, while the HPS lamp turns on and off after 1,000 switches or 1,000 hours of use, and the light efficiency is reduced by 16%.

4.2 Startup performance comparison

LED street lights are activated instantaneously, and it takes more than 10 minutes for high-pressure sodium lamps to start to reach normal brightness, and high-pressure sodium lamps consume a lot of electricity during this time. The input voltage of the LED street light can be between 90 volts and 305 volts and has no effect on the LED lights. The high-pressure sodium lamp cannot be started when the input voltage is less than 185V, and the power increases by 12% when the input voltage exceeds 245V. In this way, high-pressure sodium lamps have higher requirements on power supply lines.

4.3 Color rendering comparison

The CRI of high-pressure sodium lamps can only reach 20 to 30, while LED street lamps are generally above 70. In this way, compared with the traditional lighting, the driver can better identify the obstacles in the road and the surrounding environment of the road, and reduce the occurrence of traffic accidents. The level of color rendering directly reflects the difference in scotopic vision (S/P) between people's naked eyes. Therefore, the luminous flux emitted by the high-pressure sodium lamp must be multiplied by a correction value (0.64) to be the intensity felt by the human eye. The luminous flux emitted by LED lamps must be multiplied by a correction value (1.60) to be the intensity felt by the human eye.

4.4 Color temperature range comparison

The color temperature range of HPS lamps is 2000 to 2500, while the color temperature range of LED street lights is 2200 to 7000. If the color temperature is low, it will give people a warm feeling in winter, but it will give people a hot feeling in summer. If the color temperature is high, it will give people a cold feeling in winter and a cool feeling in summer. In general, people spend more time in summer evenings and less in winter evenings, and there is hotter weather than cold weather in a year. Therefore, relatively speaking, it is better to use white light with high color temperature as road lighting.

4.5 Light decay comparison

The light decay of LED street lamps is less than 2% at 10,000 hours, while the light decay of high-pressure sodium lamps is generally greater than 25% at 2,000 hours.

4.6 Environmental comparison

LED street lights do not contain mercury, no ultraviolet radiation, and the low working temperature effectively reduces heat emissions. Because of its power-saving, it saves coal for power generation and uses less coal to generate electricity, thereby saving carbon dioxide emissions! The high-pressure sodium lamp contains mercury and ultraviolet radiation. It emits a lot of heat during work, consumes electricity, wastes coal, and emits a lot of carbon dioxide! The PF of an LED street light is greater than 0.99, and the power factor of a high-pressure sodium lamp is about 0.44. In this way, the pollution of the LED to the power grid is very small, while the pollution of high-pressure sodium lamps to the power grid is very large! LED lamps have no stroboscopic and no light pollution, while HPS lamps have obvious stroboscopic and serious light pollution.

4.7 Comparison of effective utilization of light

Due to the characteristics of the LED light source, which is like the point light source, the illuminated object emits light in directional light. There is basically no wasted light, so it has a very high light utilization rate, which can reach more than 92%. However, because the high-pressure sodium lamp emits light from all sides, part of the light is blocked by the light source itself and the light-emitting point is large, so it is not easy to do optical design, the efficiency of the lamp is not high, and the output The light spot will not be heavy with the required effective irradiation surface and waste part of the light source, so it will be projected to the surface of the illuminated object through the reflector of the lamp, and part of the light will be lost in the middle. Therefore, the effective light utilization rate of traditional lamps is 55~60%.

5. What are the common problems with LED street lights?

Usually, LED street lights are installed on light poles, and the height of the light poles varies from 5-15m, so the quality of LED street lights is very important because once a fault occurs, the maintenance cost is very high, and a lift must be rented for maintenance. So, what are the most common problems with LED street lights? Generally, quality problems are as follows:

5.1 Problem of Surge Protection Device

Street lights are used in outdoor places and are prone to lightning strikes, so street lights are generally equipped with a 10KV surge protection device which also is named SPD, the SPD can resist multiple small-scale surges, but each time it resists, the life of SPD will be shortened until it fails, the SPD is prone to failure in areas with dense lightning. SPD is generally connected to the lamp in a parallel structure, so after the SPD fails, the lamp will not stop work immediately, but when the lamp suffers the next surge, the LED driver will suffer from surge breakdown and fail. In order to save costs, some suppliers provide street lights without SPD, so buyers need to pay attention to whether the surge is standard when purchasing LED street lights.

5.2 Problem of LED driver

The LED driver likes the heart of the lamp and is one of the most important components. When the LED driver fails, the common phenomenon is that the lamp stops working or flickers. So how to ensure that the LED driver does not fail? The best solution is to use high-quality brand driver supplies. A High-quality LED driver can not only reduce the failure rate, but also have very good electrical parameters, high power factor, and low harmonic distortion. So, what are the reliable LED driver on the market?

The video comes from youtube about the flicker of LED Street Light caused by LED Driver failure

Top Seven Brands That Manufacture LED Drivers

a.PHILIPS Xitanium LED Driver

Philips is the leading manufacturer of residential and commercial lighting products. One of the aspects that give this company an upper hand is using new technology to produce innovative LED lights led drivers, bulbs, and many other products. The company started in 1891, operates in 70 countries, and employs more than 32,000 people.

Website: www.signify.com

b.OSRAM LED Driver

Osram Led Driver Osram Licht AG manufactures Osram LED drivers for companies and individual clients. The company started in 1919 in Germany to produce electrical products. Over time, it changed its production line to focus solely on designing and manufacturing modern LED products that match users' needs and expectations.

Website: www.osram.com

c.INVENTRONICS LED Driver

Inventronics was established in Hangzhou, China, in 2007. Similar to MOSO, Inventronic's main products are LED outdoor constant current, constant voltage, High bay drivers. they also provide full global approvals. with good designs in outdoor, lightning protection, and with 5 years warranty.

Website: www.inventronics-co.com

d. TRIDONIC LED Driver

TRIDONIC GmbH Co KG, lighting products and energy-saving company located in Austria. TRIDONIC produced the magnetic ballast for the fluorescent lamp early in 1956. And later with the electrical ballast in 1978.

Website: www.tridonic.com

e.MEANWELL LED Driver

MEANWELL Switching Power Supply MEAN WELL is a Switching Power Supply manufacturer in Taiwan – SMPS, SPS manufacturer, AC DC, DC-DC, DC AC, industrial power supply, Medical power supply, Din Rail power supply, LED power supply, LED driver, charger, inverter, adaptor, rack power, and modular configurable power.

Website: www.meanwell.com

f.MOSO LED Driver

MOSO Power Technology Co., Ltd, established in 2006, is a national high-tech company, a global advanced power solution provider, and a benchmarking enterprise in the domestic power supply industry, as well as a top brand in Shenzhen, a famous trademark in Guangdong Province and even in whole China. 

Website: www.mosopower.com

g.SOSEN LED Driver

SOSEN is one of the most competitive high-power LED driver brands in China. The products are widely used in outdoor lighting, horticulture lighting, industrial lighting, landscape lighting, industrial control, etc.

Website: www.sosen.com

5.3 Problem of LED Chips

The current drives the LED chip to generate light energy, so the LEDs are the most important part of the lamp. With the development of LED technology, the failure rate of the LEDs is much lower than the LED drivers, but low-quality LEDs are also a headache. At present, the LEDs on the market are very chaotic. To save costs, some manufacturers use plastic brackets when packaging the LED chips, so that the heat inside the LEDs cannot be effectively dissipated, and it is prone to deadlights over time. So, which LEDs brands on the market are trustworthy?

Top 7 Led Chips Manufacturer

a. LUMILEDS LED Chips

Lumileds is the light engine leader, delivering innovation, quality, and reliability with our LEDs and automotive lamps. It is an LED business unit spun off from PHILIPS.

Website: www.lumileds.com

b. OSRAM LED Chips

OSRAM Opto Semiconductors is the business unit and brand of OSRAM for Opto components, solutions-based semiconductor technology for lighting as well as sensor and visualization applications. For more than 40 years, OSRAM Opto Semiconductors has been a world leader known for the highest quality demands, taking innovation to new limits.

Website: www.osram.com

c. NICHIA LED Chips

Nichia standard LED is designed and developed as a calibration standard of luminous and radiant quantities for LED products in collaboration with the National Institute of Advanced Industrial Science and Technology (AIST). It has uniform spatial distribution and has achieved excellent temperature stability and lighting reproducibility.

Website: www.nichia.co.jp

d. Seoul Semiconductor LED Chips

Seoul Semiconductor is a global LED company with sales of approximately 1.1 trillion won and third place in the global LED market in 2020. they are flexibly responding to the rapidly changing LED market by building various product portfolios with differentiated technology through approximately 12,000 patents, and are currently providing high quality LED products

through 4 local subsidiaries, 4 production bases, and 40 overseas sales offices.

Website: www.seoulsemicon.com

e. CREE LED Chips

Cree is a market-leading innovator of LED Chips Our LED chips and dice deliver superior price and performance.

Website: www.cree.com

f. Samsung LED Chips

As a forefront pioneer of LED technology, Samsung LEDs marks a new era in a global industry. Our company delivers a product line that comprises core components for LED lighting systems including modules for various uses in displays, mobile devices, automotive, and smart lighting solutions.

Website: www.samsung.com

g. Bridgelux LED chip

Bridgelux manufacture leading-edge, high-performance light-emitting diode (LED) chips with superior quality and reliability. Bridgelux chips are the basis for LED luminaires including general lighting, signage, automotive applications, and camera flash for mobile appliances.

Website: www.bridgelux.com

5.4 Problem of Optic Lens change yellow

With the continuous improvement of the light efficiency of LED street lamps, the energy-saving rate of LED street lamps is also rising. Manufacturers are constantly pursuing good heat dissipation to solve the problem of LED light decay, but they have ignored a very important factor. The optical lenses used in the LED street lights are all made of PC material. When used outdoors, the LED street lights will be exposed to ultraviolet rays from the sun, and the PC lens will gradually turn yellow, resulting in a significant drop in the light output rate. Currently, the most adopted solution is to use an anti-ultraviolet PC. Material, but this will lead to an increase in cost, so buyers should pay attention to this problem when purchasing LED lamps.

5.5 Problem of LED street lamp head falling

The material of LED street lights is mainly die-cast aluminum. In order to meet the needs of heat dissipation, some manufacturers design LED street lights of large size and heavyweight. When encountering strong winds or the light poles near the bridges or railways, the LED street lamp heads will suffer very violent vibrations, If the structure of the lamp is not strong enough, the holder of the lamp is easy to break, causing the LED street lamp head to fall, which is a very dangerous problem. If someone or a vehicle passes under the lamp pole, it will cause serious personal injury or a traffic accident. Therefore, when buyers purchase LED street lights, the vibration test report should be a mandatory requirement.

6. How to choose the power of LED street lights?

For LED street light renovation projects, many customers will ask manufacturers to recommend the power of LED street lights. According to project experience, 80-100W LED street lights are usually recommended to replace 250W traditional street lights, and 120-150W LED street lights to replace 400W traditional street lights, but The most correct way is to use professional DIALUX lighting design software, according to the actual installation conditions of the road, such as the height of the pole, the distance between the poles, the width of the road, the length of the arm of the pole, the elevation angle of the pole, the position arrangement of poles, etc., the model will be built in the DIALUX, and then the IES file of the LED street light is imported into the software, according to whether the calculation results meet the road lighting standards of various road types to confirm the suitable power of LED street light, the standards of road lighting can refer to "BS EN 13201-2-2015"

DIALUX software download: www.dialux.com, commonly version is DIALUX EVO or DIALUX 4.13

7. Important parameters of LED street lights that are easily overlooked

How to choose a good LED street lamp? Usually, high quality LED and LED power supply, high efficiency is the most important reference, because these components and performance is the main reason for the stable operation of LED street lights and the impact of energy-saving rate. But beyond that, there's one component that tends to get overlooked. What are the most important components that are often overlooked? The answer is optical lenses, also named led light diffuser.

Road lighting affects people's travel and traffic safety, so in addition to reaching the specified illumination requirements, road uniformity and glare level are very important indicators. When the uniformity is poor or serious glare appears on the road, which is likely to lead to traffic accidents.

It is the optical lens that determines the uniformity and glare level of LED street lights. After the light of LEDs passes through the optical lens, it can produce the light distribution we want. There are various road conditions, some poles are high but the road width is very narrow, some poles are very low, but the distance between the poles is large, and some poles are installed on one side, but the road width is large, so in order to meet the road standards, it is necessary to use different light distribution, For example, according to North American IESNA standard, Type I is suitable for walking path with 1 lane, Type II is for 2 lanes and Type III is for an even wider road, Type V is for the parking lot, Lens with backlight shield is suited for high way or city residential road to avoid light waste or light pollution, so when buyers choose LED street light, they should choose the ones who have a variety of light distribution for optional. MKLIGHTS as a professional manufacturer of LED street lights, all LED street lights have more than 6 different optics lenses are available, and a professional lighting design team can provide lighting simulations to determine the best one.

8. How to install LED street lights?

LED street lights have different installation methods according to different application places. Most street lights will be installed on poles, but a small number of street lights will be installed on the wall as wall washers or parking lot lights. There is no uniform standard for the dimension of poles, but the diameter of poles of 60mm is more common in the market, there is also a demand for diameters of 40mm or 76mm, If the requirement is unconventional diameter, then we can only achieve the installation through the adapter; there are also many styles of poles, most of which are round, but there are also square poles, such as American parking lots, many light poles are square, then you need to add the adapter to Install. Even some street lights will be installed on the telegraph poles, then a customized fixed bracket is needed.

The following are commonly used street light installation adapters:

10 Important Facts That You Should Know About Led Street Light

9. What is the led street light price?

There are many factors that affect the price of LED street lights, including material, performance, transportation cost, brand, etc. Below I will analyze how various aspects affect the price of LED street lights.

9.1 Material is the most important factor affecting the price

There are three main parts of LED street light components, LEDs, LED driver, and housing. At present, the LED driver and housing account for the highest cost. The price difference between branded LED drivers and unbranded LED drivers is very large. The price difference is mainly in performance. For example, brand drivers generally have better electrical parameters, high PF, low THD, and passed strict international certification, and the unbranded LED driver will have much worse indicators in order to save costs, and most of them do not have any certification; the price of the branded LEDs and unbranded LEDs is also very different, mainly Due to the difference in internal materials and processes, unbranded LEDs use cheap brackets and rough production processes in order to pursue low prices; the LED street lamp housing is made of die-cast aluminum, and the weight of the housing generally determines the quality of heat dissipation and anti-collision grade. In order to reduce costs, some suppliers design the housing to be very thin and have no heat sink or insufficient heat sink. Such housing will lead to an extremely high working temperature of LEDs, large light decay, and a short lifespan.

9.2 Performance also affects the price of LED street lights

If buyers pursue high performance, such as high luminous efficiency, they can only choose high luminous efficiency LEDs, such as LUMILEDS 5050 lamp beads, the luminous efficiency will be much higher than ordinary lamp beads, but it also means the price will be much higher, so high performance Equivalent to high prices.

9.3 Shipping costs also affect the purchase price

Importers purchase LED street lights from overseas, usually, the goods will be shipped by sea, air, railway, or express delivery. When the project procurement volume is small, they will choose express delivery or air transportation. When the project procurement volume is large, they will choose sea or railway. The volume and weight are proportional to the transport cost. The large volume and heavyweight of the packaging means that the transportation cost to be paid is high, and the transportation cost is naturally included in the procurement cost. Therefore, when choosing LED street lamps, in addition to paying attention to performance, we should also pay attention to the size and weight of the lamps. Under the requirement of sufficient heat dissipation, try to control the product size as much as possible, and pay attention not to use too much foam when packing, only in this way, the container can ship a larger number of lamps, thereby reducing transportation costs.

9.4 Brand cost affects product price

Aside from the price, for buyers, the quality of products from well-known brands is definitely more guaranteed, but the larger the brand, the higher the additional brand cost of the product, because brand promotion requires a lot of money to be invested in advertising, media, etc. For promotional activities, these costs can only be added to the product price. Therefore, for buyers, it is best to find the same product quality, but is less well-known suppliers, because the quotations of these companies will not contain too much brand cost. Of course, if the buyer does not want to rush too much energy to find such suppliers, they would rather spend a higher price to purchase products from well-known brands, and such buyers also exist.

9.5 What is the approximate price of LED street lights on the market?

Take our SE Series street light as an example, the price as below:

The wattage of SE series LED Street LightUnit Price in USD
20WUSD 70.00-77.00/pcs
40WUSD 72.00-79.00/pcs
60WUSD 75.00-82.00/pcs
80WUSD 75.00-82.00/pcs
100WUSD 96.00-106.00/pcs
120WUSD 100.00-110.00/pcs
150WUSD 120.00-132.00/pcs
180WUSD 129.00-142.00/pcs
200WUSD 131.00-144.00/pcs
240WUSD 137.00-150.00/pcs

10. How to realize intelligent control of LED street lights?

After more than half a century of development, LED has developed from a simple illuminator to a commonly used lighting fixture and then to the current intelligently regulated lighting fixture. In addition to the often-mentioned high light efficiency, long life, energy-saving, and environmental protection LED street lamps also have the characteristics of easy dimming, color matching, and high controllability, which lays the foundation for the intelligent control of LED street lamps.

The so-called intelligent control of LED street lamps is to control the brightness of the lamps by controlling the current flowing through the LED lamps. Due to the characteristics of LEDs, the color change and adjustment of lamps can also be realized through the configuration of LEDs with different wavelengths.

Modern LED intelligent control can also use Wi-Fi or ZigBee technology to interconnect lamps with sensing equipment and control equipment to form an LED intelligent control system.

The LED intelligent control system adopts a fuzzy neural network control algorithm, which can adjust the lighting brightness of LED street lamps according to environmental factors such as usage scenarios, different time periods, weather conditions, traffic flow, and vehicle speed dynamics. 

At the same time, it is also possible to use the mobile phone to remotely control the LED lamps through the wireless network technology, control the lamp switch, adjust the brightness of the lamps, control the color of the lamps, turn on the scene lighting through the mobile phone APP, and even connect the LED street lamps with the electrical appliances and supplies in the home life, Linkage control. The intelligent control of LED street lamps has changed the pattern of single lighting of traditional lamps. The light distribution is determined according to the flexible scene definition, which can give users the best lighting experience. If you are interested, please contact the MKLIGHTS team, we can provide you with a complete lighting and intelligent control system solution.

11. Conclusion

As a professional LED street light manufacturer, MKLIGHTS has rich experience in LED street light design, production, installation, and maintenance. What are the common problems of street lights, and what details need to be paid attention to when buying LED street lights, the above has been explained in detail, if you encounter other problems, you can contact the MKLIGHTS team at any time. We have a design team that can provide you with a complete set of solutions.

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14. People also ask

a. What percentage of street lights are LED?

Energy-saving technologies that make this possible? LED street lights. According to 2016 data from the U.S. Department of Energy, at least 221 cities around the world have switched their street lights to LEDs, including 30 percent of outdoor lights in the United States.

b. Why are street lights orange?

Street and industrial lights, such as those in parking lots or manufacturing facilities, emit yellow or orange light because they are sodium vapor gas discharge lamps. There are two types of sodium vapor lamps: high pressure (HPS) and low pressure (LPS).

c. How long do LED lights last?

LEDs are known for their extremely durable products. Many LEDs are rated for up to 100,000 hours of life. This is approximately 100 times longer than typical incandescent lamps, 40-50 times longer than typical halogen lamps, and 16-20 times longer than typical CFLs.

e. Do street lights change colors?

The color temperature (CCT) determines the color of the street lamp, but as the CCT increases, the color begins to change from yellow to white, and eventually to blue-white, or cool.

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