Low current systems at home. Low-current networks: design, design and installation Internal low-current networks

Low-current wiring is an integral element of the building's engineering networks, just like electrical communications, as well as the plumbing, heating or sewerage systems. The main task of a low-current circuit is to receive and transmit signals through cables operating at low currents. Devices whose operation does not require the consumption of large currents are usually connected to such a system. In the professional field, low-current cable systems also […]

Low-current wiring is an integral element of the building's engineering networks, just like electrical communications, as well as the plumbing, heating or sewerage systems.

The main task of a low-current circuit is to receive and transmit signals through cables operating at low currents. Devices whose operation does not require the consumption of large currents are usually connected to such a system. In the professional field, low-current cable systems are also commonly called information systems due to their functional purpose.

There are a number of requirements for a low current, namely:

• high reliability;
• low rate of errors and failures;
• ease of management and maintenance.

Depending on their purpose, information systems are usually divided into separate types, which have their own differences both in the equipment itself and in its functioning.

Fire alarm

A low-current system of this type is used independently or in combination with other devices that protect buildings from various types of threats. Fire alarms are designed to identify sources of fire, as well as promptly notify people of a high probability of a fire.

Such equipment, consisting of a cable, sensors, sirens and a control panel, must demonstrate uninterrupted operation, eliminating accidents, failures and false alarms.

Security alarm

The security system also includes a cable and a set of sensors that respond to changes in specified parameters.

With the help of equipment of this type, which prevents unauthorized access to a protected object, it is possible to prevent criminal attacks on material assets, as well as the life and health of people in a residential or public building.

CCTV

This information system includes a schematic placement of video cameras and a monitor to which the video signal is received. The operator located at the control panel has the opportunity to monitor the situation at different points of the controlled object.

Today, almost all administrative and public buildings are equipped with video cameras that allow you to monitor the work of staff and monitor order in the building and in the surrounding area.

Dispatching

The dispatch system solves a number of problems in managing utility networks and monitoring their correct operation. This network usually covers several separate buildings under a single monitoring and control.

ACS

Through access control, responsible persons constantly monitor the facility and also control the entrance to the building using specially equipped checkpoints. In this case, the owners of the controlled facility have the opportunity to track the number of visitors, provided that turnstiles with special counters are installed.

Computer networks

In this case, we are talking about an established network that allows you to connect the required number of computers and peripheral devices for the purpose of exchanging information within the system. This is one of the most common types of low-current systems that are installed in almost every enterprise.

SKS

The main task of a structured cable network is to combine all of the above information networks into a single whole, which allows for their centralized management and control over current processes.

Television and Internet

In addition to the cable, low-current systems of this type include decoders and routers, through which the signal is supplied from the provider to the consumer. This type of weak current has found its wide distribution in both public and residential buildings. Television cable systems are capable of transmitting both analog and the digital signal that replaced it.

Telephony

Fixed telephone communications are also based on the use of low-current systems, and can be organized both in enterprises and in the residential sector. Telephony is often one of the components of complex systems that allow organizing access to a specific subscriber in the case of multi-channel communication.

Installation features

Installation of information systems includes cable laying, as well as installation of related equipment, such as distributors, controllers, switches, sensors, sockets, etc. The installation process has a number of requirements, and always begins with drawing up a project.

Persons installing low-current circuits must comply with the following rules:

• The distance between low-current and electrical wires should be 0.5 m. The intersection angle of the wires is 90 degrees.
• Low-current systems are always laid along separate risers.
• When laying low-current systems, soldering, twisting and other connections are not allowed - only the whole cable.
• Distribution boxes must not be placed above window and door openings; however, free access to them is always ensured. The minimum distance between the ceiling and the junction box is 30 cm.
• Communication lines running along the outside of the building must be protected with special boxes, otherwise there is a high probability of damage caused by aggressive environmental influences.
• It is allowed to lay low-current wires in grooves, PVC pipes, under a concrete screed or suspended ceiling.
• In the case of hidden wiring, cable channels can be filled with wires no more than halfway, which will protect the system from overheating.

All types of low-current systems periodically require servicing or modernization. This measure will help maintain the working condition of the network without interruptions and outages.

Considering the fact that low-current networks are a complex system, their installation and maintenance must be carried out exclusively by qualified specialists in this field who have professional skills and special equipment.

1. Unprofessional installation
2. Common mistakes
3. What's the result?

Low current wires in buildings

All electrical networks in buildings can be divided into two categories: high-current and low-current. Power supplies supply alternating voltage from 220 to 380V and a current of one or more amperes for equipment and office equipment.

Low-current systems (CC) are designed to organize information interaction between operating equipment and office equipment, as well as integrate it into the global structure (Internet, communications, branches). The main distinguishing feature of the CC is the low voltage in the network, usually no more than 24V (although 36, 60V networks are also low-current) and currents no more than 100mA. The SS is characterized by a high concentration of the so-called “information flow”. To understand this, just look at the number of wires connecting to the server of even a small organization.

For any organization deploying a CC, it is necessary to immediately provide for a number of functions that need to be included during the design. Perhaps these functions are not needed now, but as the organization grows, they will be in demand, and their subsequent integration into the existing system will be more expensive, so it is necessary to foresee this in advance when designing the CC.

Regular composition of the SS:

• Telephone communications;
• Structured cabling networks (SCN) - the so-called passive equipment of local computer networks (LAN);
• Internet access;
• Fire and security alarm;
• CCTV.

Additional CC functions

• Access control and management systems - access control systems (gates, barriers, turnstiles, electronic locks, card readers, etc.);
• Automated accounting and energy management systems - ASKUE (electricity meters, water meters);
• Intercoms (PBX, selectors, intercoms);

Often in companies in the office, various departments are responsible for low-voltage networks, or as they also say, “low-voltage”. It happens that SCS is under the control of the IT department (and telephony is not in the IT department), ACS is under the security services, and automation is under the administration. Will managing such a wired infrastructure be effective?

What affects the uninterrupted functioning of low-current systems.

Most often, the installation of CC is carried out by one or two engineers of the organization in order to supposedly save money on design and installation. With this approach, only finances are saved, but not human resources. Typically this group of 1-3 people handles everything from CC calculations to purchasing and installation. Most often, the project is either not created at all, or is done hastily. Control over the created network usually passes to the employee who designed and installed the network. If he is fired, the newcomer receives a “project drawn on his knee,” with all the ensuing consequences. But even if the project survived...

Wrong choice of components

For example, if you use an uncertified cable, you will not have the information transfer speed required for your LAN. This will be especially unpleasant if it does not happen immediately, but after six months of normal operation. Your network can “fly” from 1 Gbit to 100 Mbit (and you may not notice), then ten times more, then the signal will begin to “float”, disappearing and appearing. At first, this may not affect the work of your employees: well, the 1C servers are slowing down, video surveillance has disappeared, well, they didn’t play in the tender. Just like that, “well”? No, gentlemen, no - these are indirect and direct losses, sometimes (and not so rarely) large ones. What if the network goes down while you're playing an electronic auction on the site, or the fire alarm doesn't go off? There can be many such “or”s. Why these problems?

Unprofessional installation

The use of inexpensive, unprofessional tools during installation and failure to comply with specific standards during design and installation most often leads to regular failures: “the network periodically freezes or falls off.” This happens due to the inability to provide high-quality SS contacts, which in an average organization can number in the thousands, and the appearance of electrical interference and interference. At the same time, human resources are diverted to diagnosing and eliminating the “floating” fault, which, by the way, is the most complex. Sometimes it's easier to replace an entire network segment. Expensive equipment also burns out, and it’s good if you don’t have to wait months for a replacement. And at this time something bad happens - theft from your warehouse or office

Common mistakes

The most common is when the requirements for joint installation with power networks are not met. Such a laying is possible - but you need to know how and, most importantly, follow it. Another common mistake is choosing the wrong cable. Even if it says “category 6” or something else, beautiful and serious. Actually, all equipment and components must be selected and checked especially carefully. Although, of course, there is progress, Chinese equipment is getting better, but what should you choose? There are many offers on the market, it would be a shame to miss the purchase. And, of course, our recommendation is to entrust the work “turnkey” and entrust it to professionals.

The main benefits of installation by certified companies

Firstly, the client receives a turnkey system with a set of standardized technical documents for operation. Further modernization of the system will not be difficult, since the work is carried out according to uniform industry standards.

Secondly, the speed of CC deployment depends only on the customer, because the work performed is easily scalable. To meet short development, installation and commissioning deadlines, additional necessary resources are allocated to the organization or subcontractors are involved.

Thirdly, the customer receives a guarantee for the work performed and technical support under the contract. And if the SCS is performed by a company certified by the manufacturer in compliance with the manufacturer’s requirements, then he himself gives a guarantee on the system for a period of 20 years (Legrand) or 25 years (Panduit and Hiperline).

Some people think these are empty words. This is possible if your employees undergo recertification every two years - expensive on-site training from the vendor, the optics are welded on their own equipment (costing from $10 thousand) and the quality is checked with cable analyzers for category certification (from $5 thousand). And at the same time, they are able to distinguish defective or counterfeit UTP cables, they work efficiently, and you are able to professionally evaluate and accept this work.

What's the result?

Low-current systems (SCS, telephony, access control systems - ACS, security and fire alarms, etc.) are the nerves of your office. They ensure security and business management, its smooth and reliable operation. You can find a contractor very cheaply. And perhaps the work will be at an acceptable level. But is it worth the risk?

Low current systems at home- various engineering communications that use low current for operation. The purpose of low-current systems is to power specific devices that improve human living conditions, as well as help in solving certain issues.

What do low-current systems include?

Low-current systems used in private homes include:

The following low-current systems are used in commercial use: telephony, Internet, energy metering, security and fire alarms, intercoms, local area networks, as well as structural cabling systems.
The range of requirements for low-current systems is very large and largely depends on their purpose.

Telephone

Telephony can be called the most important low-current system, since it is the most common type of remote communication between users and information transfer. Telephonization consists of:

• internal telephone network, which provides for the possibility of negotiations between people located in the same facility (without access to the external network);
• external telephone network – connecting the internal telephone network to an external line for conversations with remote users.

The subscriber must select one of the types of telephone communication. This can be analog, digital communication or PBX.

In analog systems processes are carried out through the transmission of analog signals. Examples of such devices are landline telephones, cable television, and radios.

Towards digital systems communications include systems based on digital (discrete) signal transmission. These include digital telephony, television, as well as modern communication facilities.

Currently, there is a transition to digital systems, driven by the spread of microprocessor technologies and the spread of digital networks.

Telephone network installation

After selecting the type of communication, the telephone network is carried out. This takes into account the number of telephone points and the possibility of increasing them in the future. The installation itself can be carried out in two ways: a separate cable network or in SCS, that is, structural cable systems.

The final stage is to cross cable lines (from the cross box), obtain a telephone number with the right to make long-distance calls. The user just has to put the telephone in place. Telephony can be used to use high-speed Internet access.

A television

The television system is based on the sequential transmission of parts of the image via wires or radio signals. The number of image parts depends on the radio channel bandwidth. Thus, the television system is the encoding of color and sound information. Today there are three common television systems:

1. satellite;
2. analog;
3. digital.

Satellite television is the transmission of a signal through artificial earth satellites. The main difference from terrestrial television is the large coverage area. The possibility of using satellite television is often available in remote areas where terrestrial television cannot be installed. To receive a signal from a satellite, you need to install a satellite dish on the roof of the house or on the facade of the house, which is fixed to the wall or roof of the house using a bracket. The satellite TV system also includes a receiver, cable and converter.

Another option television is analog, this system uses an analog signal to transmit data. Although today analog television is the most common, there has been a transition to digital broadcasting. Many television channels duplicate analogue broadcasts in the digital standard.

Digital television differs from analogue high definition images. In addition, the advantage of using digital technology will free up radio wave range for the new wireless network. If you want to connect to digital equipment, you must remember the limited signal coverage area and the need to purchase special equipment.

Television network installation

TV system installation consists of connecting the cable to the panel and running the cable around the house to the TV. You need to choose the right cable, since for analogue and digital broadcasting they are different and do not replace each other. In television cables, you can install dividers that separate the television signal, allowing you to connect several televisions (such systems are called splitters, splitters or crabs).
Cable wiring is carried out in hidden or open installation. The latter involves fixing the cable to the baseboard. You can hide the cable using a suspended ceiling, a plinth, placing it in a groove (and then filling the groove with a solution) or pulling the cable through the voids of building structures, which does not spoil the design of the rooms of your house. Recently, the use of special television sockets has become a popular option. You can make a couple of sockets in the room and, if necessary, move the TV from place to place.

Cables extending from the antennas must be tied and secured to the structures through which they pass (wall, roof, cable, etc.). The connection points to the antenna are sealed. It should be noted that there must be a distance of 2 m between the TV cable, electrical wiring, water and gas pipes.

As in the case of telephone cable, it is most advisable to use SCS, that is, cables that contain the corresponding television cable.

Security and fire alarm

This is a complex set of integrated technical equipment that serves to protect the house from fire and unauthorized entry. Very often it is combined with other engineering systems at home to achieve the best result.
Security and fire alarms can solve various problems, so it may include equipment from three categories:

• fire and security alarm management;
• equipment responsible for collecting and processing information;
• sensor devices (detectors and sensors).

The security alarm system notifies security services of unauthorized entry into the house (fixing the time, date and location of the incident). The security system detects the location of the fire, turns on the fire extinguishing system and notifies about the fire. For its proper installation, it is necessary to study the layout of the house or the layout of the apartment and mark the places where the elements of the security and fire alarm are attached.

Security alarm design and installation is carried out by professional organizations. The work is carried out in such a way that the units and components of the system are powered from an uninterruptible power supply. The organization performing this work organizes a plan for repair and maintenance of security and fire extinguishing systems.

Low-current networks today are available in any residential or office building. Low-current networks have been used for quite some time, but few people have any idea what it is.

A low-current system (or in common parlance a weak-current system) is a system of cables and/or wires through which a current of no more than 25 V and a current intensity of mA passes. This current is used to transmit electrical signals carrying any information. These networks are necessary for the comfort of work and living; they provide offices with the global Internet, landline telephone, cable television, fire alarms, burglar alarms and much more. We can say that the installation of low-current networks can provide a person with all the benefits of modern civilization. Low-current systems are vital, without them television and radio will stop working, telephone communications and the Internet will disappear, we find ourselves unprotected without security and fire alarms.

The complex of low-current systems includes:

Telephone installation and Internet networks;

Security and fire alarm;

Cable and satellite television networks;

Local area networks (LAN);

Video surveillance systems;

Structured cabling systems (SCS).

The operation of a low current determines the productivity of retail, warehouse and industrial buildings, as it is the core of the information infrastructure of an industrial or office building. Laying low-current networks is perhaps one of the most important points in the equipment of any room. However, unfortunately, many designers and builders believe that the installation and design of low-current systems can be successfully carried out even after the completion of the main body of work. As practice shows, after the building already has walls and the interior has already been finished, high-quality installation of low-current networks is rarely possible. Therefore, the installation and design of low-current systems should be carried out immediately after the completion of the main construction work before finishing the premises. The project must comply with strict standards, which are regulated by SNiP 083-98; it is important that the installation and design of low-current systems is carried out by professionals, especially when it comes to office space. In addition, you need to take into account certain nuances of laying a low-current network, which only experienced specialists can know.

Volgogaztelecom LLC will gladly take on the solution to all these problems. Many years of experience allow our specialists to easily perform even the most difficult tasks. In addition, our employees have all the appropriate permits and licenses that allow them to carry out such types of work.

Low-current devices in civil buildings include electrical devices of low power, and, therefore, operating at relatively low levels of voltage and current. In this regard, in low-current devices it is possible to use electrical materials that are not applicable in conventional electrical networks. To lay low-current distribution networks in buildings, vertical and horizontal special channels are provided, separated from the channels of other electrical devices. Low-current cabinets are installed on the floors of buildings, in which distribution and junction boxes of various low-current networks are located.

Radiofication. The broadcast network signal is generated at the central wire broadcasting station, then amplified and transmitted to distribution points via main feeder lines operating at a voltage of 960 V. From distribution points, a signal at a voltage of 120 or 240 V is transmitted along distribution lines to all buildings in the surrounding area.

Telephonization. Telephone installation is provided in buildings where the need for telephone numbers is more than three.

Fire alarm designed to detect the source of fire and notify fire services about the occurrence of a fire. A television.The television network for receiving television programs in buildings consists of receiving antennas and a distribution network.

Dispatcher communications. It is used in residential areas for communication and operational control of technical devices of buildings, primarily elevators. A control panel with signaling and intercom devices is installed in the control room. In the entrances, on the first floor landings and in the elevator cabins there are secondary consoles equipped with call buttons and intercoms.

Electro-acoustic system. This system is designed to enhance sound during conferences, concerts, etc.

Simultaneous translation system equipment. This system consists of power supplies, amplification and switching units and is located in the equipment room. The control room and interpreter studios must be separated by sound-absorbing materials, have good sound insulation, and have windows into the hall and between the interpreter booths. The seats in the auditorium are equipped with headphones, channel switches (for selecting the desired language) and volume controls.

Indoor television system. This system is often performed in conjunction with a simultaneous translation system or used independently for educational purposes, to facilitate the security of warehouse and retail premises, etc.

Input distribution device (IDU)

Serves for:

· connection of internal electrical networks of electrical installations to external supply cable lines;

· distribution of electricity;

· protection against overloads and short circuits of outgoing lines;

· delimitation of responsibility for the operation of electrical networks between the city network personnel and the consumer’s personnel (the ASU of the electrical networks are under the responsibility of the consumer).

They are installed:

· introductory 2-position switches, allowing for redundancy in case of failure of one of the supply lines;

· protection devices – fuses or circuit breakers;

· electricity meters;

· current transformers;

· ammeters and voltmeters;

· signal lamps;

· capacitor device for suppressing radio interference.

ASUs are made in the form of panels mounted in metal cabinets.