Usually outdoor LED displays size is large, and most of them are installed in densely populated places. The design of the steel structure should consider the foundation, wind speed, waterproof, dust-proof, moisture-proof, ambient temperature, lightning protection, surrounding population density, etc. factor. In steel structure, auxiliary equipment such as power distribution boxes, air conditioners, axial fans, and lighting need to be installed, as well as maintenance equipment such as aisles and ladders.
Outdoor LED display often exposed to the sun and rain, the working environment is harsh, and the electronic equipment is damp or seriously damp, which will cause a short circuit or even a fire, resulting in losses. Therefore, LED display screen and the joint between LED display screen and the building must be strictly waterproof and leak-proof. And the LED display should have good drainage measures. Once the water accumulates, it can be drained smoothly. Be sure to pay attention to waterproof and moisture-proof.
Ventilation and Heat Dissipation
LED outdoor display should be equipped with a ventilation and cooling device to keep the internal temperature of the screen between -10°C and 40°C. Outdoor LED screen itself will generate a certain amount of heat when it is working. If the ambient temperature is too high and the heat dissipation is poor, the integrated circuit may not work properly, or even be burned, so that the LED display system cannot work normally.
Lightning strikes can directly hit LED screen, and then leak to the ground through the grounding device. Overcurrent during lightning strikes causes mechanical, electrical and thermal damage. The solution is equipotential bonding, that is, the metal casing that is not grounded or poorly grounded, the metal casing of the cable, the metal frame in the display and the grounding device are firmly welded to prevent objects from entering due to induced high voltage or lightning strikes on the grounding device. The high potential transmission caused by the ground causes the internal insulation of the equipment and the over voltage counterattack of the cable core. Outdoor LED displays are also subject to strong electric and strong magnetic attacks caused by lightning strikes. In order to enable the large current caused by lightning strikes to be released in time, reduce the over voltage on the equipment and limit the intrusion waves generated by lightning strikes. Usually lightning protection devices should be installed on displays and buildings.
The grounding method of manufacturing LED should be considered according to the specific situation, when LED display screen is set alone, the grounding system should be set separately, and the grounding resistance is not more than 4 ohms. When LED display screen is attached to the outer wall of the building, the main body of LED display screen and the shell should maintain a good grounding relationship with the building, and share the overall grounding with the building, and the grounding resistance should not be greater than 1 ohm.
The power supply system of the LED outdoor display generally adopts AC11V / AC220V, which requires that the grid voltage fluctuation does not exceed 10%, and provides excellent system grounding. For monitors with power over 10kW, special power distribution cabinets should be set up. The power distribution cabinet with remote control or PLC control function can be selected as required, and the power distribution cabinet with PLC control function is more intelligent, and the LCD controller can be selected as required to remotely control the LED display screen production and the air conditioners, fans and other equipment in the screen It can also monitor the ambient temperature inside the screen and the ambient brightness outside the screen in real time, and have corresponding alarm information. The general environmental conditions of the outdoor display screen are poor, and it is recommended to use a distribution box controlled by a programmable controller; the indoor display screen project has better environmental conditions and limited space, so it can be operated without a programmable controller.
In order to prevent a sudden leakage fire, a leakage fire switch should also be installed at the main switch of the power inlet. The LCD control and monitoring interface in the power distribution cabinet can display the temperature inside the display in real time. When the screen is in automatic state and the temperature exceeds 65 degrees, the monitor screen will prompt that the temperature is too high, and the LCD controller will sound an alarm, and the system will automatically cut off the power to prevent fire. A smoke detector can be installed in the screen according to the actual situation. When a fire occurs in the screen, there will be corresponding prompt information on the monitoring interface, and it can also be combined with the distribution network to automatically cut off the power supply.
Post time: May-26-2022