lightning strike

Lightning protection suggestions. Because the protection of lightning and overvoltage is a systematic project, the lightning protection proposal is only to reduce the harm caused by lightning as much as possible and to protect lightning more effectively. It is recommended to design a professional lightning protection scheme.

The lightning current formed by lightning stroke is very short, but its great destructiveness is beyond human control at present. We can only try to block the energy of lightning stroke and release it into the earth to avoid the harm it brings. Only by mastering the ways of lightning hazards can we better protect against lightning hazards. The hazards of lightning are nothing more than direct strike, induction (LEMP lightning electromagnetic pulse radiation) and conduction (lightning wave invasion and counterattack).

The internal lightning protection system is set up to protect the safety of equipment and personnel inside the building. By installing a suitable lightning arrester at the front end of the equipment to be protected, the equipment, the line and the earth form a conditional equipotential body. The lightning current that may enter is blocked out, and the lightning current sensed by the internal facilities due to lightning strike can be safely discharged into the ground to ensure the safety of the connected equipment.

The lightning protection of the switch mentioned in this paper is mainly internal lightning protection, which is mainly divided into two parts:

1. Lightning protection of power supply

When the AC power cord is introduced from the outdoor and directly connected to the switch power port, the AC power port should be connected with an external power arrester to prevent the switch from being struck by lightning. Alternating current first enters the power arrester, passes through the power arrester and then enters the switch. The DC power supply has undergone AC/DC conversion more than once, and the protection conditions are good. To be on the safe side, a parallel DC power lightning arrester can also be installed outside the chassis.

2. Lightning protection of network port

For the electrical port of the switch, if wiring is done outdoors, please connect the network port arrester in series before the signal line enters the switch interface to avoid the switch being damaged by lightning.

In addition, good grounding of the switch is also an important guarantee for lightning protection of the switch. If the switch is installed on the workbench, the ground wire of the switch must be reliably grounded. If the switch is installed on a 19-inch standard rack, it is not required to connect the grounding wire, but the rack is required to have a good grounding.