As we all know, full-color LED displays occupy a large proportion in commercial display applications, and are widely used in different fields. They are divided into outdoor full-color and indoor full-color. Usually outdoor full-color screens are more than P3, while indoors are Below P3, Winbond Ying Optoelectronics will chat with you today about the protective measures of the full-color LED display system.
The LED display screen in this system is outdoor electronic equipment, which works in outdoor environment for a long time. In order to ensure the normal operation of LED display screen, it is necessary to prevent any form of water leakage into the LED display screen (especially the light-emitting components) to cause unnecessary failure.
The display module is an exposed light-emitting part installed on the front of the display screen. The basic part of the display module is a printed circuit board welded with LEDs and a driving circuit, which is installed in a shell made of engineering plastics. The front side is processed by the glue-filling sealing process and is equipped with a mask, and the back side is tightly sealed with the chassis through a waterproof rubber sealing ring. The manufacturing process technology of this outdoor display module has been very mature, and has been widely used in outdoor LED display projects by various manufacturers.
The module case that composes the display surface of the display screen has also fully considered its waterproof performance during the design. Various waterproof sealing measures are adopted. After the assembly is completed, each module case must undergo a rigorous flush test to confirm compliance with GB4208 -IP65 test requirements in the 2008 standard.
2. Damp proof
In order to prevent damp, mildew or electrical short circuit of electronic components caused by air humidity, all kinds of printed circuit boards in the display module (including the light board, control board, switching power supply and printed circuit boards in other parts) need to be three-proof Paint spray treatment. The three-proof coating used by the company is derived from the technology of Shanghai Ship Transportation Research Institute. According to the three-proof standard of ocean-going ship electronic equipment, spraying materials are configured, spraying technology is formulated, and technical workers are trained, and this measure is adhered to for all outdoor equipment.
Adopt resin sealing and potting to prevent dust. Blinds and dust filters are used on the back of the display module box to prevent dust and debris from floating in.
4, anti-electromagnetic interference
This system is designed to isolate the internal and external electromagnetic environment from the anti-interference circuit and photoelectric isolation means, to prevent the external electromagnetic environment changes from interfering with the LED display system, and passed the national testing agency GB9254-2008 and GB/T17625 in the product 3C certification .1-2003 standard test.
5. Anti-corrosion and anti-mildew
All standard fasteners in this system (including those installed inside the module box) are galvanized products to prevent corrosion.
The metal structural parts in this system are all treated with anti-rust treatment after the processing is completed. After pickling and phosphating, the anti-rust paint is first brushed and then the top coat is sprayed. The surface of the thin-plate structural parts such as the chassis are sprayed with plastic to improve the anti-rust ability and keep its appearance clean and tidy. After the metal parts are welded, they must be covered with a second coating to prevent corrosion.
6. Flame retardant
First of all, flame retardant materials are selected from the design, such as PCB board, sealant, PC shell, cable, components and so on (the flame retardant grade reaches V0); in addition, the principle of derating the components is adopted to prevent the fire caused by circuit fault.
The hazards of static electricity to the LED display are mainly aimed at the light-emitting components on the PCB circuit board and various ICs in the circuit. The company has made targeted designs in product design.
The three-anti-coating described above has anti-static function. After spraying according to the spraying process, it can cover all the exposed metal parts such as the metal pins of the components on the printed circuit board to prevent external static electricity from affecting sensitive parts.
In addition, all PCB boards are designed with good grounding measures and are reliably connected to the signal grounding terminals of the chassis and external metal components to prevent static charges from accumulating on the LED display components.
8. Windproof and earthquake resistant
The foundation of the LED display adopts a steel frame structure, which is connected by bolts or welding. The overall structure has excellent rigidity, and the overall system is safe, stable and reliable. The stress calculation of the steel structure is calculated according to the wind speed of 40m/s and the local seismic requirements. The safety factor is higher than the conventional design standard. It will not be damaged under the severe weather conditions that may be encountered in the local area, and the permanent deformation is less than 2mm. The column and beam materials selected by the company in large-scale LED display projects are all brand-name high-quality steel products. The procurement channels are stable and the material quality is very reliable.
The LED display screen needs to have reliable safety precautions, but also need to have the convenience of maintenance personnel. During the design process, the company considers both safety precautions and convenient maintenance.
9. Three-level lightning protection technology
According to the lightning conditions and the characteristics of LED display products, a comprehensive protection design for direct lightning strikes, side lightning strikes, and ground potential increase has been completed. According to the requirements of International Electrotechnical IEC1024 "Lightning Protection for Buildings" and IEC1312 "Lightning Electromagnetic Pulse Protection", three-level lightning protection technology is adopted for prevention.
According to the requirements of the IEC61643 lightning protection specification and the division of lightning protection zones in the IEC1312 lightning protection and overvoltage specifications, the lightning protection of important systems should be divided into three zones, and the low-voltage power supply system shall be protected by three levels to shunt (D) The method meets the requirements of the equipotential (B) of each line. Only single-stage lightning protection may damage the equipment due to excessive residual voltage after discharge caused by excessive lightning current or equipment damage caused by insufficient protection capabilities. The multi-level protection of the power supply system can prevent the invasion of overvoltages at all levels from direct lightning to industrial surges. The so-called hierarchical protection, which is discharged step by step, greatly reduces the lightning energy on the protected equipment.