Indoor LED display system protection measures
The LED display in this system is an outdoor electronic device that works in an outdoor environment for a long time. In order for the LED display to operate normally, the design must prevent any form of water from leaking into the LED display (especially the light-emitting parts), causing unnecessary failures.
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 a 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 been designed with full consideration of its waterproof performance. A variety of waterproof sealing measures are adopted. After the assembly is completed, each module case must undergo a strict flush test to confirm compliance with GB4208 -IP65 test requirements in the 2008 standard.
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 light boards, control boards, switching power supplies and printed circuit boards in other parts) need to be coated with three anti-coatings Spray treatment. The three-proof coating used by the company comes from the technology of the Shanghai Shipping Institute. It configures spraying materials, formulates spraying techniques, and trains technical workers according to the three-proof standard of ocean-going ship electronic equipment, and insists on implementing this measure 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. In the product 3C certification, it passed the national testing agency GB9254-2008 and GB/T17625. 1-2003 standard test.
5. Anti-corrosion and anti-mildew
All standard fasteners in this system (including those installed inside the module box) are made of galvanized products to prevent corrosion.
The metal structural parts in this system are all processed for anti-rust treatment after the processing is completed, and after pickling and phosphating, the anti-rust paint is first brushed and then the top coat is sprayed. The surface of thin-plate structural parts such as the chassis are sprayed with plastic to improve the anti-rust ability and keep their appearance clean and tidy. After the metal parts are welded, the processed surface must be covered with a secondary coating for corrosion protection.
6. Flame retardant
First, select materials that are flame-retardant from the design, for example, PCB boards, sealants, PC housings, cables, components, etc. are all flame-retardant materials (flame-retardant grade reaches V0); in addition, components are used The principle of derating is used to prevent fire caused by circuit failure.
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, the exposed metal parts such as the metal pins of the components on the printed circuit board can be completely covered 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 the large-scale LED display project are all brand-name high-quality steel products. The procurement channels are stable and the material quality is very reliable.
LED display screens need 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. In accordance with 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 should be protected by three levels to shunt (D) The method meets the requirements of the equipotential (B) of each line. Only single-level 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 over-voltage 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.