In outdoor led digital signage solutions,One of very important things is grounding for outdoor LED digital signage. The main component of outdoor LED digital signage is the LED and driver chip, a collection of microelectronics products, LED operating voltage of about 5V, the general working current of 20 mA below. It’s work characteristics determine, resistance to static electricity and abnormal voltage or current shock resistance is very fragile. This requires us in the production and use of the process to recognize this and give enough attention to take measures to protect the led digital signage. The power ground is the most commonly used LED display a protection method.
So what should the standard ground be? As shown in the following figure: There are three terminals for the power input, namely the FireWire terminal, the neutral terminal and the ground terminal. The correct grounding method is to use the ground-specific yellow-green two-color line will be all the power ground terminal connected and locked, and then lead to connect to the ground.
If there is no ground terminal on the site, you can connect to an iron tap water pipe or an iron sewer pipe and other pipes buried in the earth and in good contact with the earth. To ensure good contact, the terminals should be welded on such natural grounding bodies. The ground wire is locked on the terminal block and must not be connected. But gas and other flammable and explosive pipes and pipes shall not be used. Or buried the ground body. Grounding body can be used angle or steel pipe, horizontal or vertical buried in the earth as a simple grounding point, the ground should choose a remote place, so as not to pedestrians or vehicles damage the grounding.
We must be grounded when the grounding resistance is less than 4 ohms, in order to ensure timely leakage of leakage current. It should be noted that the lightning protection of the ground terminal in the discharge of lightning current due to the diffusion of the earth current takes some time, a short period of time will lead to increased ground potential, if the LED display ground connected to the lightning protection terminal, then the earth potential Higher than the display, lightning current will be along this line to pass to the screen body, resulting in equipment damage. So the LED display of this protection ground can not be connected to the lightning protection grounding, the protection of the ground must be more than 20 meters from the lightning protection terminal. To prevent the ground potential counterattack.
1, each power supply must be grounded from the ground terminal and locked;
2, grounding resistance shall not be greater than 4Ω;
3, ground should be exclusive wire, is strictly prohibited and zero line connection;
4, the ground may not be installed open or fuse;
5, ground and ground terminals should be away from the lightning protection terminal 20 or more;
It is strictly forbidden to protect the grounding of the equipment by means of protective grounding, resulting in protection of grounding and protection. When a protective grounding device insulation damage, the occurrence of phase line collision shell, the zero line to ground voltage, so that the protection of the device on the shell to produce a dangerous voltage.
Therefore, in the same bus-powered lines, the protection of grounding and protection can not be mixed with zero, that is not part of the electrical equipment to zero, and another part of the electrical equipment ground. The general electricity are used to take zero protection, so the use of electricity from the electrical equipment, should take the zero security.
If you want to know more about outdoor LED digital signage installation precautions, please contact Dakco.
Dakco web: https://www.dakcoled.com/