A residential building or other structure cannot be commissioned without the preliminary installation of grounding structures. If there is no ground loop, the power supply network is a gross violation of safety regulations, which are recorded in regulatory acts of SNiP, GOST, etc. The presence of a grounding and lightning protection joint venture is a prerequisite for the consideration of pre-project documents.
What is lightning protection and grounding
If the grounding equipment is out of order or does not correspond to the technical characteristics or capacities of the electrical equipment, this can lead to breakdown of the equipment or damage to a person or animal by a high-voltage discharge.
Lightning is an electric discharge, which is characterized by high power indicators. The electric field voltage of a natural phenomenon reaches several million volts, and the current strength reaches several thousand amperes. Therefore, when lightning strikes a personal plot or directly into a structure, terrifying consequences occur - household appliances will fail without the possibility of recovery, the electricity network will need to be replaced, and lightning even with a small discharge will be dangerous for human lives.
Lightning protection is a specially designed equipment that is used to prevent such consequences. Thunderstorm protection of electrical equipment in a private house and other structures is provided by changing the trajectory of the electrical discharge directed to the ground.
Grounding devices are designed to prevent accidents, the cause of which is associated with a shock due to a phase fault on the housing of household appliances or any other electrical appliance, heating and water pipes, as well as other conductive materials. The principle of operation is based on the connection of all potentially dangerous electrical appliances to the ground using conductors.
Lightning Rod Components
Lightning protection is a system of internal and external devices that prevent lightning from entering the building. Protection against damage is carried out in three stages, each of which is realized due to the proper operation of a separate component. The grounding, grounding and lightning protection scheme includes:
- Lightning rod. The main task of this part is to catch a powerful electric charge that has come from outside. It is required to install this working unit at the highest point of the structure with the help of wooden supports. Visually, it looks like a rod made of metal. The length ranges from 20 cm to 1.5 m, the diameter is not more than 12 mm, and the minimum cross-sectional area is 100 mm sq.
- A down conductor is a conductor in the form of a wire that connects to an air terminal. Its main task is to conduct a discharge through itself to the ground electrode. A characteristic feature of the part is its exceptional resistance to heavy loads (more than 200,000 Amperes), which it transfers without deformation, modification or other destructive processes. The installation involves welding it on the one hand to the air terminal, and on the other hand to the ground electrode. An important condition is that the mount is reliable and strong, otherwise the lightning does not go into the ground, but inflicts a crushing blow on a residential building or other structure.
- The last integral part of the design is the ground electrode. Visually, it looks like an ordinary sheet made of metal.It must be buried in the ground, the optimal depth in the soil is 1-2 meters. Designed part for the dissipation of current in the soil.
The structure of the lightning protection system is not characterized by complex technical aspects. Everything is quite simple, but effective.
Types and types of grounding protection, lightning protection
A lightning protection system redirects lightning from a building to the ground. With the help of conductors, a hazardous discharge moves away from hazardous areas, reliably protecting housing, household appliances and electrical appliances, as well as the health and lives of all households. To protect yourself 100%, you need to install the structure as far as possible from home, as well as communication systems. A great danger is the collision of a lightning discharge with a gas pipeline.
There are two types of lightning protection:
- external (external);
- internal.
An external lightning protection system is also called passive. Several work units present a failure, the task of which is to redirect a direct lightning strike. Consists of lightning protection from an air terminal, a down conductor and a grounding device.
The main task of internal protection is to equalize the potential on metal cases, devices in the room. This happens with the help of arresters and surge arresters.
To ensure complete safety, you need to take care of the construction of external protection and organization of internal. The cost of two types and their installation is a costly business, but this will allow in the future to save considerable amounts for the restoration of burned appliances, etc.
Active system
To carry out calculations of active lightning protection, it is required to take an increase in the radius of protection as a basis. The system is a special equipment that ionizes air near itself, attracting a lightning discharge to a specific place.
The advantage of this protection is that it is installed once and does not require maintenance. The diameter of the working area reaches 80 meters. Mount a meter higher than the highest point of the structure.
Lightning conductor designs
The upper part of the lightning protection system installed at the highest point of the building, it is divided into several types:
- Rod receiver. Its feature is the pointed end. It is in him that lightning strikes during a thunderstorm. They are produced, as a rule, from a copper pin with a diameter of 15 mm. The location should be high enough, but not excessive, otherwise the device will independently attract all electrical discharges to itself. It has an attractive appearance.
- The advantage of the cable version is that it creates a large protective radius, unlike analogues. Cable structures are used in power line devices. They do not use metal pins, but a cable, which is connected to other working parts using bolts.
- There are also mesh designs. Their peculiarity lies in the fact that a mesh made of metal is installed on the roof of the house.
There is a pattern - the greater the length of the metal pin (rod, cable receiver), the larger the area of the protected area.
The protective system must be installed directly on the building, at the highest point of the structure. The grounding segment is dug into the ground to disperse the discharge, it is connected to the air terminal using a conductor. There is no need to check and inspect lightning protection devices, it is enough to install the system once.
