Wiring structure lightning protection weak current wiring system
Some optical cables and weak current wiring systems, assuming there is no certain maintenance measures, are easily attacked by lightning, which will not only cause economic losses, but also threaten human life more seriously. So what can we do to avoid encountering lightning?
According to the different functions of electrical and microelectronic equipment, different maintenance procedures and certain protection points of the maintenance layer, classified maintenance is carried out; according to the electrical path that the lightning hazard may invade, complete the maintenance of each system from power lines to data communication lines, network cables, optical cables, etc. Abort multi-level, multi-level maintenance.
1. External passive maintenance
Passive maintenance is performed outside the 0-level maintenance area, mainly including lightning rods (nets, wires, strips) and grounding installations (grounding wires, ground poles). Maintenance principle: When the thundercloud discharge is close to the air, it distorts the electric field in the air. At the top of the lightning rod (line), the inter-office electric field intensity distortion is formed to affect the development direction of the lightning pilot discharge, guide the lightning to discharge to the lightning rod (line), and then go through the grounding down wire, and the grounding installation will introduce the lightning current into the ground, so that the lightning current is introduced into the ground. Protect objects from lightning strikes.
2. Disposal on the ground
In the establishment of computer rooms and various weak current rooms, it is necessary to have a good grounding system, because all lightning protection equipment needs to leak the lightning current into the ground through the grounding system, so as to maintain the safety of equipment and people. If the grounding system of the computer room is not done well, it will not only cause equipment defects, burn out components, but also seriously endanger the lives of staff. In addition, there are anti-interference shielding problems and anti-static problems, which need to be solved by establishing a good weak current wiring system.
3. Internal protection
Partial protection of power supply, lightning damage is mainly through the intrusion of power supply lines. The "power lightning arrester" is connected to the power line in parallel to contain transient overvoltage and discharge surge current. Three-level protection is usually provided from the main incoming line to the end of the electrical equipment. After step-by-step voltage limiting and discharge, the lightning energy is gradually eliminated to ensure the safety of the electrical equipment.
Local signal maintenance, for various signal systems, should be divided into rough maintenance and precision maintenance. The level of rough maintenance is determined according to the level of the maintenance area to which it belongs, and the level of precision maintenance is determined according to the sensitivity of electronic equipment. After the "signal lightning arrester" is connected to the signal line, on the one hand, it must be able to cut off the path of lightning entering the weak current wiring system, and at the same time, it must be able to quickly discharge to the ground. Not damaged, so that the equipment can work normally.