Before starting today's topic, we can't "do nothing". Let's take a look at the production process of LED fluorescent lamps:

Now the production of LED lights must first go through rigorous computer programming, make the lamp board, and then enter the assembly line of the assembly workshop. We will not start any more.

Everyone has such a life experience. The LED lights that have just been bought are always very bright, but after a period of time, many lights will become darker and darker. Why do LED lamps have such a process?

Let's take a look at it today! To understand why your LED lights are getting darker and darker, we must first understand a professional term-LED light decay.

LED light decay refers to the LED after a period of time after the light, its light intensity than the initial light intensity will be reduced, and can not be restored, that is, the reduced part of the LED light decay.

The more LED lights are used, the darker they are because the LED lights will have light decay.

LED lamp light decay is the light in the transmission of the signal weakened, and at this stage of the global LED factory to make LED products are different degrees of light decay, high-power LED also exist light decay, which has a direct relationship with the temperature, mainly by the chip, fluorescent powder and packaging technology decision. At present, the light decay of white LED on the market is one of the primary problems to enter the civil lighting.

Light attenuation generally refers to its luminous flux, when charging the surface of the photosensitive drum, as the charge accumulates on the surface of the photosensitive drum, the potential is also rising, and finally reaches the "saturation" potential, which is the highest potential. The surface potential will decrease with the passage of time. Generally, the potential at work is lower than this potential. This potential naturally decreases with time, which is called the "dark decay" process. When the photosensitive drum is scanned and exposed, the potential of the dark area (refers to the surface of the photoconductor not irradiated by light) is still in the dark decay process; the bright area (refers to the surface of the photoconductor irradiated by light) the carrier density in the photoconductive layer increases rapidly, the conductivity rises rapidly, the photoconductive voltage is formed, the charge disappears rapidly, and the surface potential of the photoconductor also decreases rapidly. It's called "light decay".

LED lights with the more dark, is a very common phenomenon. In addition to the light decay, can make LED lights dim, nothing more than the following two points.

LED lamp beads are required to work at DC low voltage (below 20V), but our usual mains power is AC high voltage (AC 220V). To turn the mains into the electricity needed for the lamp beads requires a device called "LED constant current drive power supply".

Theoretically speaking, as long as the parameters of the driver match the lamp bead board, it can be continuously powered and used normally. The internal drive is more complex, any device (such as capacitor, rectifier, etc.) failure, it is possible to cause the output voltage change, and then cause the lamp to dim.

Driver damage is one of the most common faults in LED lamps, which can be solved after replacing the driver.

The LED itself is composed of a combination of lamp beads, if one or part of it is not bright, it is bound to make the whole lamp dark. Lamp beads are generally connected in series and then in parallel-so if a lamp bead burns down, it may cause a batch of lamp beads to fail to light up.

There are obvious black spots on the surface of the burned lamp bead. Find it, connect it to the back of it with a wire, and short-circuit it; or replace a new lamp bead, which can solve the problem.

The LEDs occasionally burn one, probably by chance. If you burn frequently, you should consider the drive problem-another manifestation of drive failure is burning the lamp beads.

Why does the LED light flash? What is the reason why the LED light flashes...

There is a capacitor in the driver of the LED lamp, which can be understood as a rechargeable battery with a small capacity: when current passes through the capacitor, the capacitor will continue to charge-after fully charged, the capacitor will release all the stored energy at one time.

LED lights flicker, it belongs to the latter situation: the capacitor charging process, the lamp is extinguished-due to the capacitor internal current is small, resulting in charging speed is very slow, so with the naked eye can see the lamp extinguished. When the capacitor is fully charged, a one-time release of electrical energy, will light the lamp. However, due to less stored electrical energy, the lights will soon go out-repeated charging and discharging, and the naked eye can see the lights flashing.

When the lamp is used normally, no flicker is seen because the current through the capacitor is large and the charging speed is extremely fast.

First of all, because the quality of the capacitor is not good-high-quality capacitor, a lot of stored electricity, the tiny current in the line is not enough to store energy in the capacitor. The average starter is only about 20 yuan, and the cost of high-quality capacitors is probably more than 20 yuan.

In addition, we can also start with the source of small currents.

The switch controls the zero line, which represents the live line directly connected to the electric light (capacitor). And there is a high potential on the live line, if there is a low potential in the line at this time, it will form a potential difference-another name for the potential difference, called voltage. However, the potential difference at this time is much smaller than that of 220V. When a voltage is added across the capacitor, a weak current is generated.

Therefore, the direct access of the fire wire to the lamp will inevitably lead to the flashing of the LED lamp. This is a construction problem, in addition to changing the direction of the zero line of fire, there is no other way.

Both ends of the lamp (capacitor) are connected to the zero line of zero potential. Is everything all right? Not really! The neutral wire is easily charged-especially the neutral wire of an electric lamp. Mainly because the light switch is so unreliable.

Now the light switch, the quality of the internal structure is very worrying. Zero fire wire terminal distance is too close, insulation is not qualified, etc., are likely to cause the electric lamp zero line charged. If you don't believe it, you can take apart the switch that has been connected in your home and test it with an electric pen-theoretically, when the switch is turned off, only the live wire terminal can light the electric pen. However, in actual use, nine times out of ten, the terminal connected to the zero line (light line) can also light the electric pen.

However, most switches, even if the neutral line is charged, carry a relatively low voltage, which is not enough to generate current in the line. However, if the insulation is even worse and the generated current is slightly larger, the capacitor will be charged.

One more thing: when the switch is equipped with an indicator light, the indicator light will light up when the light is turned off, and a weak current needs to be generated at this time-this part of the current will flow through the capacitor and be stored by the capacitor. These situations can be solved by replacing a switch with a better quality and no indicator light.

If there are many wires around the capacitor, when other wires are working, induced electricity will be generated near the capacitor-a word to explain the cause of induced electricity: two conductors are placed in parallel to form a new capacitor.

Most people are helpless in the face of this situation. At this time, there are two solutions:

1) Replace the electric lamp with fluorescent lamp or incandescent lamp.

2) Connect a 220V relay coil in series on the starter of the LED lamp. The coil is used to consume the induced electricity generated by the disconnected circuit.