Causes Of The Light Decay Of LED Street Light And Practical Solutions Share

Why are LED street lights getting darker and darker?What causes the flashing of LED lamp?LED light decay is one of causes resulting in these problems.Well,what is the light decay,what causing the light decay and how to solve it.Don't worry!This lighting blog post will share the comprehensive answer one by one.

Led lamp fixtures have light decline problem, which is an universal phenomenon.Different LED products, the light decay strength is different.The LED lighting industry standard is zero light decay for 1000 hours ,1% for 3000 hours,3% for 10000 hours,30% for 50000 hours.In general,it is regular led lighting lamp manufacturer if reach the above industry standard.

What is LED light decay?

LED light decay refers to that the light intensity will be lower than the original light intensity after a period of lighting of LED, and the lower part is LED light decay.The brightness of all the light source will be lower than its initial after a period of use.So the light decay is also related to the service life of LED lamp.The acceptable light decay is 50%-60% before led lighting lamp fixtures reach its end of life.Light decay is one of the elements to show the lamp quality.The quality of led lamp with low light decay is higher.Therefore, it is necessary to choose outdoor led lighting products with low light decay.

What causing the light decay of led street lamp?

The heat dissipation problem of led street light

Temperature is actually the key element causing the light decay of LED road light.The luminous power of LED street light is higher than household lamps, so led street light manufacturers take great pains in the design of heat dissipation substrate fin and heat dissipation module.After assembly, it is necessary to add paint outside the heat dissipation module of the lamps to prevent climate erosion.Unexpectedly, the spray paint of the external protection sealed the heat of the heat dissipation module back, resulting in poor heat dissipation,so as to causing the problem of LED light decay.

In addition to the heat dissipation problem of LED lamps, this blog post also summarized the following two factors leading to light decay.

The quality of LED product itself

1.LED chip quality is not good, brightness attenuation faster

2.Due to the defects in the production process, the heat dissipation of LED chip cannot be well exported from the PIN, resulting in the high temperature of LED chip and aggravated the attenuation of led lamp brightness.

Driver

1.LED is driven by constant current, while some LEDS are driven by voltage, which makes LED attenuation excessive.

2.Driving current is greater than rated driving condition.

To sum up, there are many reasons for LED light decay, but the most critical one is heat dissipation problem.So the solutions to heat dissipation problem of led lamp will effectively improve the light decay defect,so as to greatly increase the lifespan of led street lights.

Solutions to light decay problem of LED street light

3 practical solutions was listed as below:

1.It is suggested that led street light manufacturer start from the basic materials,and solve the problem of high power LED heat source from the inside out.

2.To use the right thermal conductive adhesive, soft ceramic thermal conductive adhesive is recommended.For example,thermal conductive adhesive plays a key role during the bonding of the luminescent component to the aluminum substrate.Some manufacturers think that the thermal conductivity of thermal adhesive film or thermal adhesive pad should be good, the thicker the film, the better, but did not think of the thermal resistance problem.No matter how good the thermal conductivity is, it is useless to encounter the thermal resistance of the film thickness.What's more, the thermal conductive film or soft thermal conductive gasket can not really close with the substrate, and there are many pores in the bonding surface.When viewed under an electron microscope, these pores look like empty air pockets, another form of thermal resistance.There are so many thermal resistance factors that interfere with heat conduction, the efficiency of heat dissipation and conduction is invisibly reduced.

3.Soft ceramic heat dissipating paint for LED lamps is recommended.This kind of soft ceramic heat dissipation paint can be directly sprayed on the outside of LED road lighting lamps, the construction operation is simple, can adapt to various shapes of heat dissipation structure, can also be adjusted into different colors, according to the needs of landscape design.

It is a very common phenomenon that LED lights get darker and darker after a period of use.In addition to light decay, there are another 2 reasons that can make LED lights dim.That is:drive is damaged,the LED is burned.

LED lamp beads are required to work at dc low voltage (below 20V), but our normal mains electricity is AC high voltage (AC 220V).The electricity needed to turn mains into lamp beads requires a device called an "LED constant current drive power supply".In theory, as long as the parameters of the driver are matched with the lamp bead board, it can continue to supply power and normally use.The internal of driver is more complex, any device (such as capacitor, rectifier, etc.) occur failure, may cause the output voltage change, and then cause the lamp dimming.Driver damage is the most common failure in LED lamps, usually can be resolved after the replacement of the driver.

LED itself is composed of a combination of lamp beads one by one, if one or part is not lit, it is bound to make the whole lamp dark.Lamp beads are connected in series and then in parallel,so if one lamp bead burns, it can cause a whole batch of them to fail.One LED is burn, probably by accident.If burn out frequently,the driver problem should be considered - another sign of driver failure is the burned lamp bead.