Views:79 Author:Site Editor Publish Time: 2019-09-09 Origin:Site
Lightning protection refers to the protection technology that prevents the damage caused by direct lightning strikes or lightning electromagnetic pulses on the building itself or its internal equipment by forming an integrated system that intercepts and guides the final discharge into the ground.
Lightning protection grounding is divided into two concepts, one is lightning protection, to prevent damage caused by lightning strikes; the other is grounding, an electrical using measure to ensure the normal operation and personal safety.
The earthing device is a general term for the grounding body and the grounding wire. Its function is to introduce lightning current into the ground. The protection of the lightning protection system is greatly related to this. The characteristics of the grounding project itself determine the impact of the surrounding environment on the engineering effect. It is not feasible to design the grounding system separating from the specific conditions of the project site. Practice requires a systematic grounding theory to guide the actual project. The quality of the design depends on a combination of factors in the local soil environment. The factors such as soil resistivity, soil structure, water content and allowable construction area determine the shape, size and process material selection of the grounding wire. Therefore, when designing the artificial grounding body, it should be accurately designed according to the geological conditions such as soil resistivity and soil layer distribution of the grounding grid.
Grounding body: It is also known as a earthing electrode, it is a metal conductor or conductor group that are in direct contact with the soil. It is divided into artificial grounding body and natural grounding body. The grounding body acts as a conductor that is in intimate contact with the earth's soil and provides electrical connection with the earth, it safely distributes the thunder energy to the earth.
In the grounding design, various metal structures, pipes, and equipment that are reliably connected to the ground are used as the grounding body, which is called a natural grounding body. If the resistance of the natural grounding body can meet the requirements and does not pose a safety hazard to the natural grounding body, it can be used as a grounding body when there is no mandatory specification.
The conductor buried in the ground as an earthing device is called an artificial grounding body. Metal objects that meet the requirements of the grounding requirements are generally buried in a subterranean depth. If the resistance meets the specified requirements, it is used as a grounding body. The lightning protection grounding, equipment grounding, and electrostatic grounding should be separated.
Grounding is the most important part of lightning protection engineering. Whether it is direct lightning protection or lightning static induction, electromagnetic induction and lightning wave intrusion protection technology, the lightning current is finally sent to the earth. Therefore, without good grounding technology, it is impossible to have a qualified lightning protection process. The function of the protective grounding is to make a good metal connection between the uncharged metal part of the electrical equipment and the grounding body, reduce the grounding voltage of the contact, and avoid the danger of human electric shock.
A metal conductor that plays a role of dredging that is buried in the soil or the concrete in direct contact with the earth, it is called the grounding body. The grounding body is mainly divided into two types: natural grounding body and artificial grounding body. All kinds of metal members that are directly in contact with the earth, metal well pipes, foundations of reinforced concrete buildings, metal pipes and equipment, etc are called natural grounding body. The grounding metal conductor used in the buried ground is called artificial grounding body. It includes copper-clad steel grounding rod, copper-clad steel grounding pole, copper-clad flat steel, electrolytic ion grounding pole, grounding module, and “high-conductivity module”.