Practical LED display screen tips, come and learn more!

1. A certain area of the LED display screen frequently experiences dead lights or caterpillars (8 or 16 LED light beads, one or three of which have a damaged wick causing a short circuit, which is essentially a malfunction of two rows of LED lights). After a period of repair, the exact same fault occurred again in the exact same place. The reason for this malfunction is that the air conditioning system has a close contact with the display screen, causing improper display of dead lights and caterpillars in the upper right corner of the display screen. Change the position of the air conditioner or approach the display screen, and the fault will be eliminated and will no longer occur.

2. One side of the central air conditioning is facing towards the display screen without a mouth, and the LED display screen area facing towards the mouth without a mouth repeatedly malfunctions. Therefore, when using indoor LED display products, it is prohibited to place the air conditioner's mouth close to the display screen!

3. A display screen installed in an indoor conference room, with a layer of "condensation water" on the surface of the screen for a period of time, causing dead lights and caterpillars to fill the screen.

4. Why does a large amount of condensed water solidify on the surface of the screen? Through on-site inspections, it was found that:

Behind the display screen is the central air conditioning, while behind the screen is the vertical cabinet air conditioning. The air conditioning is not on and off at the same time, and the environmental temperature difference between the screens is less than 10 ℃ or more. The display screen is designed with an ambient relative humidity of less than 75%. This creates conditions for condensation water. A large amount of condensation water solidifies on the surface of the display screen, and the larger the temperature difference and relative humidity value, the more serious the phenomenon of condensation water becomes. This is similar to the fogging of the air in the car during winter on the surface of the car glass. And when using LED display screens, it is necessary to avoid significant temperature differences between the display screens and control the relative humidity of the environment. If the relative humidity is less than 75%, air conditioning sterilization or additional dehumidification equipment should be carried out.

5. The improper malfunction similar to the "comet tail" on the surface of the screen is due to the installation of the display screen in the KTV. The customer accidentally sprayed liquid such as alcohol, milk, and juice onto the surface of the display screen, and the cleaning personnel carried out routine flushing and cleaning, resulting in such improper behavior! Moreover, in the process of using LED display screens, if the surface of the display screen is injured or contaminated by foreign objects, especially conductive liquids, the power should be turned off as soon as possible, and then a dedicated screen cleaning solution should be used to clean it in a timely manner.

6. After installing a display screen in a relatively dry area in the north for a period of time, caterpillars appeared everywhere on the entire display screen. The inspection showed that there was vibration on the surface of the screen structure. Further analysis was conducted on some improper LED light beads of the screen, and the reason for the damage of the light beads was due to a large amount of current penetration. Why were the LED beads on that screen damaged? Originally, in the circuit design of the AC220V output terminal according to the national 3C mandatory standard, the power supply manufacturer would connect an EMI filtering circuit from the live wire to the ground wire to ensure the stability of the AC220V output, and all power supplies would have filtering leakage during operation. When the LED display screen is not functioning properly, leakage current can cause damage to the IC or lamp beads.

So, this fault is caused by electrostatic discharge due to the display screen not being grounded.


笔记