Low-current networks: design, installation and installation

Low-current networks are an element of the building's engineering system. In principle, virtually any cable network can be called low-current if the cables are not power, but information currents, whose voltage ranges from 12 V to 24 V, and which vary exclusively in milliamperes.

Requirements for low-current networks

Among the basic requirements that today's low-current networks must meet are:

• Extremely high reliability.
• Stable work without any possible failures or errors.
• Relatively low cost for installation and operation.
• Scalability.

Due to the possibility of using low-current systems, it is now possible to provide virtually any type of communication, as well as to ensure the normal operation of computer networks. Depending on what is the purpose of a specific network, and where it will be used, they are all divided into commercial and household.

What are they needed for?

Using low-current networks, you can:

• Reception, as well as the subsequent distribution of both terrestrial and satellite television.
• Providing access to the telephone network of communication.
• Normal operation and provision of access to the Global Network.
• Design of wire broadcasting networks.
• Normalization of the effective operation of security and fire systems.
• Normalization of the effective operation of warning and signaling systems.
• Use of access control systems for various objects (automatic control of barriers, gates and turnstiles.
• Fully automated accounting system for managing various energy resources (water meters, electricity meters, home automation systems).
• Works of local-computer networks.
• Interaction between the intercoms.
• Full structuring of cable systems.

Installation

Before the installation of low-current networks will be carried out, a full-fledged project of the future network is formed and, in particular, the future location of the switchboard, relays, sockets, and all other nodes that will be part of this system will be accurately determined. Being engaged in laying all kinds of cables, installers perform all the work in accordance with specialized rules, as well as approved standards.

What is included in the installation?

In itself, the installation of low-voltage networks includes: the laying of telephone, computer or television lines, the installation of specialized information outlets, as well as other means of communication, the installation of intercoms, video surveillance, security and fire alarms and other equipment.

rules

In this case, there are several important rules that must necessarily be observed when laying low-current networks:

• The minimum distance at which laid power and low-current cables should be parallel is to be at least 0.5 m, and if they intersect, then the angle of intersection should be 90 ^° . The distance between the paved lines of the Internet network, as well as the specialized power cables, may be less than this distance, because during the transmission of digitized signals they are not affected by any interference.
• In no event shall low-current cables be wound in the riser in which other electrical wires are located.
• It is forbidden to splice the wires. Routing of cables must be carried out exclusively with the use of a single wire.
• In the event that the telephone network wires are laid in one direction, they must be laid in parallel and at the same time tightly pressed against each other.
• If the device of low-current networks and systems is not in concealed wiring, then the minimum distance at which they are with the telephone network cables must be at least 15 mm in case the line length is 10 m.
• The junction box should be located directly on the wall, but do not forget that it is strictly forbidden to place it above doors, windows or various apertures. The minimum permissible distance at which the junction box should be located on the wall relative to the ceiling is 300 mm.
• Cables of different capacities that intersect each other must be adjacent to the wall, or they must be bent from above or below, depending on what capacity these cables have.
• Without fail, in the process of laying cables, provision should be made for their protection. This is especially required by external low-current networks, which are installed under windows or downspouts, since they are most susceptible to various damages and for this reason require the use of metal linings.
• Any low-voltage network lines must necessarily have a grounding with a dedicated bus, which is made up of carefully insulated copper conductors. Such conductors are used to connect the distribution metal box directly to the ground line itself.
• If the design of low-voltage networks provides for the open laying of telephone network cables, then they should be at least 200 mm away from the floor, and from the ceiling should be at a distance of more than 150 mm. If it is a closed method of laying, then in this case the cables can be located at any convenient height.
• In the event that different digitized signals are transmitted along the network lines, then low-voltage electrical networks can be located on walls in stitches, specialized PVC sleeves in the raised floor or screed of floors, and may be suspended from false ceilings.

Do not know how to do it? Trust professionals

The design of low-current networks, as well as their subsequent installation, should be performed only by qualified specialists who have a long working experience in this field. After all, depending on the literacy and quality of all the work will directly depend on how well the signal, communication, and how reliable and durable the operation of all equipment will be. In addition, the quality of conducting low-current operations also affects the safety of equipment during its operation.

Telecommunication Equipment

The use of telecommunication equipment is encountered in almost any case, when low-current networks of various types of data are laid, and communication is established between several devices. In this case, the quality of the equipment used and the materials that will be present during the construction of low-current networks directly depends on how well all the installation work is carried out.

Telecommunication equipment includes two main elements.

Passive network equipment

• A set of connecting cables, which includes fiber optic cable and twisted pair.
• Connecting components, as well as a patch cord, designed to connect different devices to each other.
• Switching panels, including cross-plates for cable routing and direct fixation of cross-over units, as well as a patch panel designed for wiring in a rack and a signal wiring closet.
• Cable, as well as panel connectors for signal transmission. The use of these elements is also found in the patch panels, and depending on the number of contacts present, all types of such devices are divided into two-contact and three-contact ones.
• Information outlets, equipped with modular connectors and designed to be installed in cable channels.
• Modular jacks, which are used for the formation of cable networks, as well as the configuration of telecommunications outlets. These jacks are included in the modular panels and sockets. In order to connect the active equipment, the technology of the insulated contact through the insulation is applied, and depending on the cable used, nests of various categories can be used.

Cable Boxes

• The switch cabinet, which is located directly inside the room and is used to connect the wires to the terminal contacts of the terminal blocks, and also to provide termination of the cables.
• Instrument racks, which are used to locate and integrate various devices of digital broadcasting systems.
• Cable boxes that are mounted in places of transition to air communication lines. Such boxes are used as effective protection of cable lines against all kinds of external influences or overvoltage.
• Distribution telephone boxes, providing switching of connecting wires in communication systems.

What cables are used in such networks?

For a full-fledged laying of a computer, television or telephone network, different types of cables are used.

If it is a question of laying computer low-current systems and networks, then in this case copper cables of "twisted pair" format from category 5e and 6, belonging to class B and E respectively, or specialized fiber-optic cables, are used.

If you need to build telephone networks, then in this situation it is enough to use standard low-current cables of the 3rd category. At the same time, when installing low-current networks, it is necessary to use electrical cables, through which data transmission can be conducted at a clock frequency of up to 1 MHz. The use of the same optical cables is most often encountered when it is necessary to lay the backbone networks, since their use is necessitated by the extremely high data transfer rate. The cable brand is initially indicated in the wiring diagram.

How are the networks laid?

Depending on how the cable is located, low-current networks can be laid:

• Under the ground . In this case, the cables are laid in specially designated lines of underground communications, which are also called cable sewers.
• Above the ground . Here, cables are airlifted from one house to another or in places where wires are suspended on power lines.
• Closed manner . Cables are laid in specially designated trays in order to exclude the possibility of causing the network of any damage.
• Open way . This kind of laying is provided only if there is no possibility of causing any damage to the network.

In the process of selecting a cable, it is important to take into account not only where it can be used and what technical characteristics it has, but also pay attention to ensuring that the entire network is in compliance with fire safety conditions.

conclusions

If you are not familiar with cable management, then you should not even try to do all the work yourself. It is much better if all the procedures, from the selection of cables to the subsequent installation of the entire system, including maintenance of low-voltage networks, will be handled by qualified specialists who have been professionally working in this field for several years and know all the details of carrying out such work.