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How to solve the problem of light decay of LED lamps
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How to solve the problem of light decay of LED lamps

(Summary description)   When the LED lamp is used for a period of time, we will find that its light is not as bright as it was at the beginning. This is because the service life of the LED lamp is coming to an end, so the phenomenon of the light decay of the LED lamp appears. So, what causes the light failure of LED lamps? How to solve the problem of light decay of led lamps?        What is light decay? At present, my country has not yet formulated the definition and general standard of light decay, but generally speaking, light decay refers to the fact that after a period of lighting, the light intensity of LED lamps will be lower than the initial light intensity and cannot be recovered, that is, the reduced part is Light decay of LED lamps. (Different types of lamps have different causes of light decay)       In addition, the US Energy Star LM-80 stipulates 6000H, and the luminous flux maintenance rate ≥ 94.1% is considered invalid.        Causes of light decay of led lamps and lanterns As for the cause of light decay, there is still a lot of controversy, and the microscopic mechanism that causes the decay is still inconclusive, but generally speaking, the light decay of LEDs is mainly caused by heat dissipation. It is well known in the industry that LEDs are afraid of heat. The ideal working temperature of LEDs is between -5°~0°, but this is basically impossible. Heat will affect the light decay and life of LED lamps. When LEDs are working, they will About 80% of the electrical energy is converted into light energy. The LED heat sink is used for LED heat dissipation, because when the LED chip is working, its own ambient temperature is inversely proportional to the light output rate. The higher the temperature, the lower the light output rate. , when the temperature reaches the maximum operating temperature of the LED chip, the lamp will be broken. In addition, the thermal resistance of the LED chip itself, the influence of silver glue, the heat dissipation effect of the substrate, and the colloid and gold wires also have a certain relationship with the light decay.      How to solve the light decay of led lamps and lanterns In fact, in a strict sense, LED lamps cannot avoid light decay. It is a technical problem that the industry is concerned about urgently to solve. However, as long as we understand the heat dissipation method of lamps, we can minimize the problem of light decay. But before talking about the heat dissipation of LED lamps, we must first understand it: What is junction temperature? The so-called junction temperature is the operating temperature of the PN junction of the semiconductor chip (wafer, bare chip), and the higher the junction temperature, the earlier the light decay occurs. If the junction temperature is 105°, and the brightness is reduced to 70%, the life is only over 10,000 hours, and 95° has 20,000 hours, and when the junction temperature is lowered to 75°, the life is 50,000 hours, and at 65°, it can be extended to 50,000 hours. 90,000 hours. Therefore, the key to prolonging the life is to reduce the junction temperature, and the key to reducing the junction temperature is to have a good heat sink. So how to systematically identify the heat dissipation of LED lamps and lanterns?        Generally, as the junction temperature of the LED increases, the luminous flux will decrease. Then, as long as we measure the illuminance change of the lamp at the same position, we can reverse the change of the junction temperature. The specific method is: 1. Choose a place that is not disturbed by outside light, preferably at night, and turn off other lights. 2. Turn on the light in a cold state, and immediately measure the illuminance of a location. At this time, the reading is "cold illuminance". 3. Keep the position of the lamps and illuminometer unchanged, and the lamps continue to work. 4. After half an hour, read the illuminance value here, and write down the reading as "thermal illuminance". 5. If the two values are similar (10~15%), the heat dissipation system of this lamp is basically good. 6. If the two values are very different (greater than 20%), the cooling system of the lamp is questionable. The "half-hour illuminance method" simply measures the junction temperature change.      In addition, we can't judge the quality of the radiator just by looking at the cost. We have to choose the most cost-effective one, not the best one for everything. Therefore, the editor's summary is: 1. The radiator is very hot when you touch it by hand, which is definitely not good. If the radiator is not hot when you touch it by hand, it is not necessarily good. 2. In the case of reasonable design, the same weight, the larger the surface area, the better the radiator. 3. The same surface area, the heavier weight, the better the radiator. (The premise is the same material) 4. The fins of the fin radiator are not as many as possible, the denser the better.

How to solve the problem of light decay of LED lamps

(Summary description)
  When the LED lamp is used for a period of time, we will find that its light is not as bright as it was at the beginning. This is because the service life of the LED lamp is coming to an end, so the phenomenon of the light decay of the LED lamp appears. So, what causes the light failure of LED lamps? How to solve the problem of light decay of led lamps?

 



 

  
What is light decay? At present, my country has not yet formulated the definition and general standard of light decay, but generally speaking, light decay refers to the fact that after a period of lighting, the light intensity of LED lamps will be lower than the initial light intensity and cannot be recovered, that is, the reduced part is Light decay of LED lamps. (Different types of lamps have different causes of light decay)


      In addition, the US Energy Star LM-80 stipulates 6000H, and the luminous flux maintenance rate ≥ 94.1% is considered invalid.




 

 

  
Causes of light decay of led lamps and lanterns

As for the cause of light decay, there is still a lot of controversy, and the microscopic mechanism that causes the decay is still inconclusive, but generally speaking, the light decay of LEDs is mainly caused by heat dissipation.

It is well known in the industry that LEDs are afraid of heat. The ideal working temperature of LEDs is between -5°~0°, but this is basically impossible. Heat will affect the light decay and life of LED lamps. When LEDs are working, they will About 80% of the electrical energy is converted into light energy. The LED heat sink is used for LED heat dissipation, because when the LED chip is working, its own ambient temperature is inversely proportional to the light output rate. The higher the temperature, the lower the light output rate. , when the temperature reaches the maximum operating temperature of the LED chip, the lamp will be broken. In addition, the thermal resistance of the LED chip itself, the influence of silver glue, the heat dissipation effect of the substrate, and the colloid and gold wires also have a certain relationship with the light decay.




 

  
How to solve the light decay of led lamps and lanterns

In fact, in a strict sense, LED lamps cannot avoid light decay. It is a technical problem that the industry is concerned about urgently to solve. However, as long as we understand the heat dissipation method of lamps, we can minimize the problem of light decay.

But before talking about the heat dissipation of LED lamps, we must first understand it: What is junction temperature? The so-called junction temperature is the operating temperature of the PN junction of the semiconductor chip (wafer, bare chip), and the higher the junction temperature, the earlier the light decay occurs.

If the junction temperature is 105°, and the brightness is reduced to 70%, the life is only over 10,000 hours, and 95° has 20,000 hours, and when the junction temperature is lowered to 75°, the life is 50,000 hours, and at 65°, it can be extended to 50,000 hours. 90,000 hours. Therefore, the key to prolonging the life is to reduce the junction temperature, and the key to reducing the junction temperature is to have a good heat sink. So how to systematically identify the heat dissipation of LED lamps and lanterns?


 



 

  
Generally, as the junction temperature of the LED increases, the luminous flux will decrease. Then, as long as we measure the illuminance change of the lamp at the same position, we can reverse the change of the junction temperature. The specific method is:

1. Choose a place that is not disturbed by outside light, preferably at night, and turn off other lights.

2. Turn on the light in a cold state, and immediately measure the illuminance of a location. At this time, the reading is "cold illuminance".

3. Keep the position of the lamps and illuminometer unchanged, and the lamps continue to work.

4. After half an hour, read the illuminance value here, and write down the reading as "thermal illuminance".

5. If the two values are similar (10~15%), the heat dissipation system of this lamp is basically good.

6. If the two values are very different (greater than 20%), the cooling system of the lamp is questionable. The "half-hour illuminance method" simply measures the junction temperature change.




 

  
In addition, we can't judge the quality of the radiator just by looking at the cost. We have to choose the most cost-effective one, not the best one for everything. Therefore, the editor's summary is:

1. The radiator is very hot when you touch it by hand, which is definitely not good. If the radiator is not hot when you touch it by hand, it is not necessarily good.

2. In the case of reasonable design, the same weight, the larger the surface area, the better the radiator.

3. The same surface area, the heavier weight, the better the radiator. (The premise is the same material)

4. The fins of the fin radiator are not as many as possible, the denser the better.


Information
  When the LED lamp is used for a period of time, we will find that its light is not as bright as it was at the beginning. This is because the service life of the LED lamp is coming to an end, so the phenomenon of the light decay of the LED lamp appears. So, what causes the light failure of LED lamps? How to solve the problem of light decay of led lamps?
 
njtansuo.com
 
  

What is light decay? At present, my country has not yet formulated the definition and general standard of light decay, but generally speaking, light decay refers to the fact that after a period of lighting, the light intensity of LED lamps will be lower than the initial light intensity and cannot be recovered, that is, the reduced part is Light decay of LED lamps. (Different types of lamps have different causes of light decay)


      In addition, the US Energy Star LM-80 stipulates 6000H, and the luminous flux maintenance rate ≥ 94.1% is considered invalid.

njtansuo.com
 
 
  

Causes of light decay of led lamps and lanterns

As for the cause of light decay, there is still a lot of controversy, and the microscopic mechanism that causes the decay is still inconclusive, but generally speaking, the light decay of LEDs is mainly caused by heat dissipation.

It is well known in the industry that LEDs are afraid of heat. The ideal working temperature of LEDs is between -5°~0°, but this is basically impossible. Heat will affect the light decay and life of LED lamps. When LEDs are working, they will About 80% of the electrical energy is converted into light energy. The LED heat sink is used for LED heat dissipation, because when the LED chip is working, its own ambient temperature is inversely proportional to the light output rate. The higher the temperature, the lower the light output rate. , when the temperature reaches the maximum operating temperature of the LED chip, the lamp will be broken. In addition, the thermal resistance of the LED chip itself, the influence of silver glue, the heat dissipation effect of the substrate, and the colloid and gold wires also have a certain relationship with the light decay.

njtansuo.com
 
  

How to solve the light decay of led lamps and lanterns

In fact, in a strict sense, LED lamps cannot avoid light decay. It is a technical problem that the industry is concerned about urgently to solve. However, as long as we understand the heat dissipation method of lamps, we can minimize the problem of light decay.

But before talking about the heat dissipation of LED lamps, we must first understand it: What is junction temperature? The so-called junction temperature is the operating temperature of the PN junction of the semiconductor chip (wafer, bare chip), and the higher the junction temperature, the earlier the light decay occurs.

If the junction temperature is 105°, and the brightness is reduced to 70%, the life is only over 10,000 hours, and 95° has 20,000 hours, and when the junction temperature is lowered to 75°, the life is 50,000 hours, and at 65°, it can be extended to 50,000 hours. 90,000 hours. Therefore, the key to prolonging the life is to reduce the junction temperature, and the key to reducing the junction temperature is to have a good heat sink. So how to systematically identify the heat dissipation of LED lamps and lanterns?

 
njtansuo.com
 
  

Generally, as the junction temperature of the LED increases, the luminous flux will decrease. Then, as long as we measure the illuminance change of the lamp at the same position, we can reverse the change of the junction temperature. The specific method is:

1. Choose a place that is not disturbed by outside light, preferably at night, and turn off other lights.

2. Turn on the light in a cold state, and immediately measure the illuminance of a location. At this time, the reading is "cold illuminance".

3. Keep the position of the lamps and illuminometer unchanged, and the lamps continue to work.

4. After half an hour, read the illuminance value here, and write down the reading as "thermal illuminance".

5. If the two values are similar (10~15%), the heat dissipation system of this lamp is basically good.

6. If the two values are very different (greater than 20%), the cooling system of the lamp is questionable. The "half-hour illuminance method" simply measures the junction temperature change.

njtansuo.com
 
  

In addition, we can't judge the quality of the radiator just by looking at the cost. We have to choose the most cost-effective one, not the best one for everything. Therefore, the editor's summary is:

1. The radiator is very hot when you touch it by hand, which is definitely not good. If the radiator is not hot when you touch it by hand, it is not necessarily good.

2. In the case of reasonable design, the same weight, the larger the surface area, the better the radiator.

3. The same surface area, the heavier weight, the better the radiator. (The premise is the same material)

4. The fins of the fin radiator are not as many as possible, the denser the better.

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What are the characteristics of LED roadway lights? Do you know the installation method and precautions? Take a look!

What are the characteristics of LED roadway lights? Do you know the installation method and precautions? Take a look!

  As people's requirements for lamps are getting higher and higher, a new type of lamps called LED lamps are favored by people. LED is a kind of light-emitting diode. As a light source for illuminants, it has high light efficiency and long life. To achieve multi-purpose lighting, and softened, it will not cause dazzling or other uncomfortable reactions, so many public areas will use this kind of light, such as LED roadway lights, because there are many people on the road, so it is necessary to To install soft lamps that will not hurt the eyes, what are the characteristics of LED road lights? Do you know its installation methods and precautions? Let's follow the editor to learn about it.    Features of LED roadway lights: 1. The color purity of LED roadway lamps is high; at present, LED products cover almost the entire visible spectrum range, and the color purity is high. 2. LED roadway lamps have a long life. The actual life of LED is more than 50,000 hours, which is several times or even dozens of times that of general light sources. 3. The light source of LED roadway lamps does not contain mercury, and the light beam does not contain ultraviolet rays. 4. It is solid luminescence, good shock resistance, firm and reliable. 5. It also has the characteristics of energy saving, economical and maintenance-free. 6. LED has strong luminous directionality, high luminous flux utilization rate, and small size, which is easy to design and control light intensity distribution of LED lamps. 7. LED roadway lamps can be powered by DC low voltage, which is safe and reliable. 8. The LED is not limited by the start-up temperature, it can be started temporarily, usually a few ms, and can temporarily achieve full luminous flux output.   Installation method and precautions of LED roadway lights: 1. Installation method: 1. First, determine the installation position and method of the lamps according to the actual needs of the work site, and then prepare the corresponding length of Φ8~Φ14 mm three-core cables according to the distance from the lamps to the power contacts. 2. Open the set screw on the side of the upper cover of the lamp, then loosen the compression nut of the cable inlet of the lamp, open the upper cover, and lead the power cables through the compression nut to the internal terminal, and connect according to the method shown in the figure. Fix it, and then tighten the cable compression nut and the upper cover of the lamp. 3. The LED roadway lights are enclosure-free. If the lamps themselves are not bright, generally communicate with the manufacturer for direct replacement or return to the factory for maintenance. 2. Notes: 1. The power supply must be cut off before dismantling the lamp. 2. It is strictly forbidden to open it with electricity. 3. During use, the surface of the lamp has a certain temperature rise, which is a normal phenomenon; the center of the transparent part has a high temperature and should not be touched. 4. When installing lamps, the lamps should be safely grounded nearby. The above are the characteristics of LED roadway lights, as well as its installation methods and precautions. Relevant staff must pay attention to the problems during installation to ensure their personal safety.
Warm congratulations to Tanso Optoelectronics for obtaining four product safety and explosion-proof certificates!

Warm congratulations to Tanso Optoelectronics for obtaining four product safety and explosion-proof certificates!

Warm congratulations to Tanso Optoelectronics for obtaining four product safety and explosion-proof certificates!
DGS51/127LW (A) mining explosion-proof LED tunnel induction light

DGS51/127LW (A) mining explosion-proof LED tunnel induction light

DGS51/127LW (A) mining explosion-proof LED tunnel induction light is a specially designed lighting device used to provide reliable lighting effects in mining tunnels. This lamp adopts LED technology and has an explosion-proof design, which can operate safely in harsh environments such as humidity, dust, and explosive gases.

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