Visit：2288   Date：2023-11-13

The light attenuation of LED lamp products is the weakening of the signal of light during transmission. Currently, the light attenuation level of LED products produced by large LED factories around the world is different, and high-power LEDs also have light attenuation, which is immediately related to temperature, mainly caused by integrated ICs, phosphors, and packaging processes. At present, the light attenuation of white light LEDs in the sales market is one of the main challenges in entering civilian lighting fixtures.

Light decay generally refers to its lumen value. When charging the surface battery of the photosensitive drum, the potential continues to rise along with the accumulation of positive charges on the surface of the photosensitive drum, ultimately reaching the "saturation state" potential, which is the maximum potential. The surface potential will decrease with time, and the potential during operation is generally lower than this potential. The entire process of this potential decreasing over time is called the "dark decay" process. When the photosensitive drum is exposed by the scanner, the shadow (referring to the surface of the photoconductor that is not directly exposed to light) potential is still in the entire process of dark decay; The bright area (referring to the surface of a photoconductor that is directly irradiated by light) rapidly increases the relative density of free electrons in the light conducting layer, and the conductivity rapidly increases, generating a working voltage for light conduction. Positive charges quickly dissipate, and the surface potential of the photoconductor also sharply decreases. It is called "light decay".

LED lights become darker and darker, which is a very common situation. In addition to light attenuation, there are many other reasons that can cause LED lights to dim, but they are all the following three points.

Controller damage: LED beads are regulated to operate under low DC voltage (below 20V), but the usual voltage is AC high voltage (220V AC). To convert voltage into the necessary electricity for the lamp beads, a device called an "LED constant current power LED driver" is necessary.

In theory, as long as the main parameters of the controller match the lamp bead board, the system can be continuously powered and everything can be applied normally. The internal structure of the controller is relatively complex, and common faults caused by any device (such as capacitors and electronic rectifiers) are likely to cause changes in output voltage, resulting in dim lighting fixtures.

Controller damage is one of the most common faults in LED lighting fixtures, and can generally be resolved after replacing the controller.

LED damage: The LED itself is composed of one lamp bead after another, and if one or some of them do not light up, it will inevitably cause all lighting fixtures to dim. Lamp beads are usually first connected in series and then connected in series - therefore, if a certain lamp bead is damaged, it is highly likely that a batch of lamp beads will not light up. There are significant small black spots on the surface of the damaged lamp bead. Find it and connect a cable to its back to short-circuit it; Alternatively, dismantling and replacing a new lamp bead can solve the problem. Sometimes an LED is damaged, which may be coincidental. If it is frequently damaged, it is important to consider the controller problem - another major manifestation of common controller malfunctions is damage to the lamp beads.

LED light decay: Simply put, light decay refers to a sharp decrease in the chromaticity of the emitting material - these conditions are more pronounced on fluorescent lamps and tubes. LED lights also cannot prevent light decay, but their light decay rate is very slow and it is generally difficult for the human eye to see the transition. But they do not eliminate fake and inferior LEDs, or fake and inferior light beads, or various factors such as poor heat removal, which cause the LED light decay rate to become faster.

How can LED lights flash? There is a capacitor inside the controller of LED lights, which can understand the capacitor as a low-power rechargeable battery. When the capacitor is filled with electricity, it will continuously charge the battery - once it is full, the capacitor will release all the stored magnetic energy at once.

The flashing LED light belongs to the latter condition: during the charging process of the capacitor battery, the light is flashing - because the internal current of the capacitor is small, causing the battery to charge slowly, the light can still be seen to go out with the eyes. When a capacitor is filled with electricity, it releases electromagnetic energy at once, which illuminates the lamp. However, due to the limited amount of stored electromagnetic energy, the light quickly needs to be extinguished - continuously charging and discharging the battery, causing the light to flicker. When the electric light is used normally, it cannot flicker because the battery charging rate is fast due to the large current of the capacitor.

So, what causes a smaller amount of current to pass through the capacitor? The first reason is that the quality of capacitors is not very good - excellent capacitors store a lot of electricity, and the subtle electrical flow in the route cannot be stored within the capacitor technology. A typical driver only costs around twenty yuan, and the cost of high-quality capacitors may not be just twenty yuan. In addition, everyone can also start from the source of subtle electrical flow.

Probability 1. Power switch operating zero line: The power switch operating zero line means that the live line zero line is immediately connected to the lamp (capacitor). The zero line of the fire line has a high potential, and if there is a low potential in the current route, there will be a potential difference - another name for the potential difference, called the working voltage. It's just that the potential difference at this point is much smaller than 220V. When the working voltage is applied to both sides of the capacitor, it will cause a very weak current flow. Therefore, immediately connecting the zero line of the live line to the electric light will inevitably cause the LED light to flash. This belongs to the engineering construction problem, and there is no other method besides changing the orientation of the zero fire line.

Probability 2. Zero line charged: If both sides of the lamp (capacitor) are connected to a zero potential zero line, is everything going smoothly? Not entirely! The zero line is very easy to power on - especially the zero line of an electric lamp. The key is that the power switch of the electric light is too unreliable. The quality of the internal structure of current light power switches is very worrying. The distance between the zero line terminals is too close, and the insulation performance is not good, which is likely to cause the zero line of the electric lamp to be electrified. I don't believe it's possible to disassemble the power switch that has already been connected to my home. Use an electric pen to measure it. In theory, when the power switch is turned off, only the live and zero wire connectors can illuminate the test pen. However, in practical applications, nine out of ten cases, the wiring lug connected to the neutral wire (light wire) can still illuminate the test pen. Just the vast majority of power switches, even if the zero line is live, the required working voltage is relatively low and cannot cause current flow in the circuit. But if the insulation performance is even worse, causing a slight increase in the amount of current, it will charge the capacitor battery. When the power switch is equipped with a flashing light, the display light will flash when the light is turned off, which must cause a very weak current flow - this part of the current flow will flow through the capacitor and be stored by the capacitor. This situation can be resolved by replacing the power switch with a higher quality one without a display light.

Probability 3. Induced Current: If there are many cables around the capacitor, other cables will cause induced current around the capacitor during operation. In one sentence, the reason for the generation of magnetic induced current is that two electrical conductors are placed parallel to each other, creating a new capacitor. Most people are at a loss to deal with this situation, and there are two solutions: 1. Replace the electric lamp with a fluorescent tube or fluorescent lamp. 2. Connect a 220V automotive relay electromagnetic coil in series on the driver of the LED light. The induced current caused by the consumption of a circuit with an electromagnetic coil.