Installation of low-current networks includes a complex of works. Low-current networks include: security and fire alarms, warning systems, paid alarm systems, video surveillance, intercoms, access control systems, local and computer networks, telephone lines. Each type of installation of a particular low-current system has its own installation nuances, but all this work has approved state standards.
In most cases, the standards for installing low-current networks are aimed at ensuring safety in the premises in case of unforeseen situations. An important role in the installation of low-current networks is played by the aesthetic component, because, you see, hanging wires in a reputable office will not look very nice. Therefore, in such cases, special channels are used in which all the necessary equipment is laid. During installation, the location of electrical and other wiring and power points is taken into account. If the wires are laid openly, then they should be no lower than 2.3 m from the floor and no closer than 5 mm to the ceiling. All networks must be equipped with grounding. Eventually, installation of low-current networks should ensure not only high-quality signal transmission and maintaining safety in the room, but also provide an aesthetic appearance.
Refers to the main type of installation work. Low-current networks are the nervous system of any enterprise or organization and serve various purposes. Low-current networks include computer, local, computer networks, fire alarm systems, video surveillance systems, telephone networks, intercoms and others.
A responsible undertaking, because the reliability and quality of the network will depend on the quality of installation work. Installation of low-current networks can be done in different ways, which include underground and overhead, closed and open cable laying. Underground installation is carried out through underground communications, and overhead installation is carried out through the air. The closed installation method involves laying the cable in special trays to avoid damage. Wires are installed in an open manner so that they are not in danger of being damaged.
It is also worth noting that closed routing of wires is more aesthetically pleasing, in contrast to open routing. High-quality installation of low-current networks is the key to long-lasting and uninterrupted operation of the network.
Where does the installation of low-current networks begin?
Installation of low-current networks allows us to take full advantage of many opportunities of modern civilization. Reliable and correct operation of computer local networks, flawless reception of several dozen television channels, stable and uninterrupted operation of security and fire alarms, high-quality telephony. And all this right in your apartment or in your office. Experts compare the low-current network with the human central nervous system for a reason. It permeates all rooms and premises, combining, as a result of high-quality installation, all existing communication channels into a single information whole: telephony, television and the Internet.
You can start talking about installing low-current networks even outside the walls of a building or structure. After all, the wires still need to be connected to it. They do this in a variety of ways: they use existing underground communication lines (or lay new ones), power line supports, and transfer cables from one house to a neighboring one. When developing modern projects for administrative premises and residential buildings, the installation of low-current networks is included as part of a complex of internal works that should provide the facility with power supply. And we must admit that this decision is perhaps the most correct. Otherwise, after completion of construction, interior and finishing work, in order to lay new communications, it will be necessary to re-open the floors and disturb the interior decoration of the walls and ceilings.
Problems that can be solved by installing low-current networks
Objectively speaking, the installation of low-current networks is actually a whole complex of rather diverse works. Since such networks can safely include fire and security alarms, video surveillance systems, warning and access control, various computer and local networks, intercom devices and telephone lines, paid state and commercial alarm systems. Installation of low-current networks in each of the above cases has its own rather characteristic nuances. They are united by the requirement to strictly comply with existing approved state standards. Let's talk about them in a little more detail. For the most part, these standards are focused on strictly ensuring safety requirements in premises where low-current networks are installed, in the event of various types of unforeseen situations. It is imperative to take into account how electrical and other wiring and related power points are located. When laying in an open way, the cables must be located from the floor at a height of at least 2.3 meters, but no closer than 5 millimeters from the ceiling. Naturally, all networks must be grounded. The installation of low-current networks is also carried out taking into account the preservation of the aesthetic appearance of the premises, using special channels, with the help of which the equipment necessary for high-quality signal transmission and proper security is masked.
Each of us knows that all electrical appliances in the house operate on a voltage of 220 V. This is a fairly high voltage that requires a lot of energy and can seriously injure a person.
But there are also a number of devices and systems that do not require high voltage. Such electrical appliances are called low-current systems.
All household electrical equipment is designed to perform fairly complex processes and requires high currents. For low-current systems, this is not at all a necessary condition. The main area of application of such systems is data transmission devices:
- Internet;
- telephone communications;
- various alarms and video surveillance;
- TV.
The mechanism of operation of information transmission systems is simple: data encrypted with a special code is transmitted at high speed and using low voltage.
Types and scope of application of low-current systems
Along with the already listed household applications, low-current systems are used in industrial settings, such as: automated electricity metering, cable systems, computer networks, switching devices (PBX), etc.
Depending on the role of application, the systems under consideration are either user or commercial.
Among the most popular and most important for life are the Internet and telephone communications. Thanks to telephony, each of us is able to easily contact the desired subscriber at any distance. Connecting to the World Wide Web can also be done via telephone wires, but in this case the connection speed will be low, so the most relevant for the Internet is the use of fiber optic wires, which have a higher information transfer speed.
Television transmits images via cable or radio waves. To carry out this type of information exchange, satellite and household receiving antennas are required.
Video surveillance includes a wide range of devices designed to monitor small (apartments and offices) and large (industrial facilities) premises and buildings.
Various types of alarms responsible for many types of security. The basis of most types of warning systems are motion sensors or devices that respond to an open circuit. If an intruder has entered the building, the sensors transmit information to the security console. Fire alarms work in a similar way; heat and smoke become the trigger.
All low-current systems listed above are designed to create a comfortable and safe life. They do not require high currents, and therefore they are harmless to health and economical.
Installation of low-current systems and documentation for it
Low-current systems are invaluable and useful assistants in our daily lives. Failures and malfunctions in their work sometimes cause great inconvenience. To prevent such annoying problems, it is very important that the design, installation and maintenance of such systems is carried out only by appropriately qualified specialists.
All basic and necessary requirements used for the design and installation of low-current systems are specified in the following list of documentation:
- GOST 21. 101-2009. General provisions for the preparation of design documentation used in construction;
- SNiP 3. 05. 06-85. Preparation, implementation and commissioning of electrical installation work;
- RD 78. 36. 002-99. Recommendations for the use of security and warning systems and their designation;
- PUE 7. Requirements for electrical lighting of premises;
- RD 78. 145-93. Preparatory, installation and commissioning works of warning and alarm systems;
- NPB 105-03. Classification of premises and buildings according to fire safety level.
Any of the low-current systems, when installed according to the rules of this documentation, will become the key to safe and comfortable human life.
Project of low-current enterprise networks. IOS Section 5
The enterprise's low-current systems project includes the following networks:
Structured cabling system (SCS)
This low-current project provides for the connection of workplace equipment (phones, desktop computers and other active equipment) and network equipment into a single local area network of the enterprise. All connected points are located on the premises, in accordance with the reconstruction plan. The project is planned to be implemented on active switches Cisco third level with the possibility of stacking(connection of switches by a high-speed bus, combining them into a single complex). The main cross-connection of the building is provided for the telephone exchange room in building 3 rooms. 285 m. Horizontal cross-connections are located in the corridors of buildings in wall cabinets installed at a height of 2.3 m from the floor level. The network topology is star.
The SCS provides the ability to connect both existing analog telephone sets and the ability to connect I. P . telephony To connect I. P . telephony requires modernization of the PBX - installation of additional I. P . modules. Modernization of the automatic telephone exchange is not provided for in this project. The project provides for the gradual replacement of the old telephone network with a modern structured cabling system. The developed system is designed with reserve for subsequent expansion and integration with other engineering networks.
Closed circuit television system (CCT)
CCTV serves for centralized monitoring of technological equipment.
Building 5 provides for installation of the system IP video surveillance.
The following video recording devices are included: I. P. video cameras:
To record the movement of people and the operation of technological equipment in the testing room, it is planned to install stationary video cameras B03618FIR. The cameras have a day/night function, which allows high-quality recording of images at illumination up to 0.05 lux. Video cameras record with a resolution of 1280x960 p ., 25 fps. Video cameras are installed in sealed thermal housings with dust and moisture protection IP66.
Video cameras are mounted on brackets to the walls.
The company's hardware and software complex is provided as receiving equipment that provides recording, compression, and storage of video, processing and the possibility of software analysis of the video archive Macroscop . The video server is installed in the main distribution center in building 3 rooms. 285. The video server is designed with the ability to connect up to 32 video cameras, with the calculation of reserve and transfer of the existing CCTV system to IP technology in order to improve the quality of video recording and data processing.
Video signal transmission is provided over twisted pair cable, using the power of the SCS section of this project.
A twisted UTP 4x2x0.52 cable is used as a cable for transmitting a video signal from the camera to the SKS hardware cabinet cat .5 e 4 p , manufacturer "Paritet".
The video cameras are powered according to the 1st category, through the provided uninterruptible power supply installed according to the SKS project in the cabinet. The UPS provides a system battery life of at least 30 minutes. The video cameras are powered through a switch Cisco with POE technology , with power supply via signal cable. These switches can also be used to create additional jobs.
The video surveillance system incorporated in this project is modular and has the possibility of expansion and modernization. The operator's workstation can be performed at any workstation connected to a structured cabling network. Software for operator work with the system is free; the number of operator jobs is limited by the system at the software level. The project assumes two operator positions in building 5, room 3 (observation cabin) and in building 8, room 100 (security post). Workplace equipment: PC, monitor, peripherals - the project does not provide for it and there are no special requirements for equipment.
project Unified Time System (UTS)
The system synchronizes the installed clocks from the GNSS GLONASS satellite and GPS NAVSTAR with an accuracy of no worse than ±100 μs, and provides automatic transition to winter/summer time.
The system allows you to synchronize time and date on computers connected to the enterprise LAN.
The system is self-healing.
There are five main beams from the clock station through free pairs in the SCS to buildings 1, 2, 5, 9, 11, respectively.
The following are accepted as secondary clocks in the project:
- SVS-40 watch with a display diameter of 400mm, single-sided, classic design.
The loops for synchronization and control of the secondary clock are carried out using a twisted pair cable KSVVG 1x2x0.75.
The station has its own backup battery. This will allow it to maintain the functionality of the entire system for at least 4 hours during a power outage.
The clock system is a category I consumer of electricity; its power supply is provided from two independent power supply sources:
· main input: ~220V, 50 Hz.
· backup input: from a 2200 VA uninterruptible power supply installed in the cabinet in the SCS section in the cabinet.
The power consumed by the clock system does not exceed 100W
Cables and wires of the system are laid:
- according to the provided cable-supporting structures in the SCS section of this project.
- in rooms and corridors without a false ceiling - in a TMS mini-channel 22x10 mm.
- in rooms and corridors with a false ceiling - in a PVC pipe with a diameter of 20 mm
- through partitions and interfloor ceilings to a water and gas pipe with a diameter of 25 mm.
Access control and management system (ACS)
The project provides for an access control and management system of the “vestibule-gateway” type and control of passage through the reader to the entrance and exit.
The basic principle of operation of the Tambour Gateway ACS is that there is a ban on opening the door included in the gateway until all other doors are closed.
To implement this logic, equipment from the Bolid company based on S-2000-2 controllers was adopted. These controllers have a standard “Vestibule Gateway” function for two doors (see equipment data sheet).
Contactless readers are used to enter the vestibule gateway, and a button is provided to exit the vestibule.
To exit in the event of an emergency, emergency “Exit” buttons are provided, which at the physical level turn off the power to the electromagnetic locks.
For local control of the system, an existing S-2000 remote control is provided at the security post in building 8.
For centralized control of the system, a cable with an interface is provided R.S. -485, using the reserve in the SCS for a free pair.
Switching network controllers using protocol RS-485 indoorsprovided by cable ParLan F/UTP Cat 5 e. ng (A) - HF 4 x 2 x 0.52 (Ethernet).
The connection of devices is provided by the signal cable KSVVng-(A)-LS 2x0.8 and KSVVng-(A)-LS 2x0.4
Cable installation in rooms and in corridors should be carried out in a cable channel.
Network controllers are mounted on the inside of the protected premises to provide protection against unauthorized access.
Power supply to control panels is carried out according to power supply category I.
Cables and wires of the system are laid:
- in office and domestic premises without a false ceiling - in a 10x22 cable channel;
Security alarm (OS)
The security alarm is designed to detect unauthorized entry into protected premises and transmit notification of unauthorized entry to the round-the-clock duty post in building 8, room 100 for the purpose of timely notification.
The premises, according to the reconstruction and technical re-equipment plan, are planned to be equipped with:
- volumetric optical-electronic, addressable detectors type S2000-IK isp.02, to protect the interior of premises.
- magnetic contact, addressable detectors type S2000-SMK Estet, for protecting doorways.
As equipment for receiving signals about the activation of security detectors, a receiving and control device of the “S2000-KDL” type is used, which is connected via the existing and designed in 1060-2011-2П-ПБ RS 485 interface with a symmetrical cable to the “S2000M” monitoring and control panel installed in the security room in building 8, room 100. The RS-485 interface is common for burglar alarms and fire alarms.
The addressable security alarm loop is made using cable KSVVng(A)-LS 2x0.8 and is connected directly to the control panel.
Arming and disarming is carried out by an arm/disarm command received via the RS-485 interface from the S2000M control panel.
Reception and control devices are installed in ShPS cabinets, with built-in uninterruptible power supply units RIP-12RS. The cabinets are taken into account in the project 1060-2011-2P-PB and have a reserve.
Cables and alarm wires are laid:
- according to the provided cable-supporting structures in the SCS section of this project.
- in office and domestic premises without a false ceiling - in the TMS 22/1-10 minichannel,
- in rooms and corridors with a false ceiling - in a PVC pipe with a diameter of 20 mm
- through partitions and interfloor ceilings in a water and gas pipe with a diameter of 25 mm.
The power supply of the designed control and control devices "S2000-KDL" is carried out according to the I category of power supply through redundant power supply units RIP-12 RS with batteries provided for in the PB project
In-site warning system (IAS)
The designed intra-facility warning system is a universal system and serves for:
I. Transmission of civil defense and emergency signals.*
II. Alerts people about a fire with an automatic voice message and audible tone.*
* I - III priority level
The installation of the system is carried out in premises subject to reconstruction and technical re-equipment.
Voice messages are entered from the META 8581 control panel and the main META 9401 notification control device. The project provides for 1 control panel installed at the security post, building 8, floor No. 1, room No. 100.
The choice of speakers and their installation location are determined taking into account the area of the premises and the operating noise level. The following types of speakers were used in the project:
Wall speakers ASR-3.1.5 maximum power 3W. They are installed in premises subject to technical re-equipment and reconstruction, in accordance with the plans.
To ensure independent reportingand reception of civil defense and emergency signals, the project provides for the installation of subscriber loudspeakers of the type “ Meshchera AG-01 "power 1 W.
To provide the enterprise with urban radio broadcasting, the project provides for the installation of 3 radio stands and a TAMU-10S subscriber transformer on the roof of the building.
Provide grounding of the pipe stand with metal wire with a diameter of 4 mm. Connecting the pipe stand to the city radio broadcast is carried out as a separate project.
Connect to the city's radio broadcast network in accordance with the technical specifications for connection from the Federal State Unitary Enterprise RSVO No. 481/457 dated April 17, 2014.
Power supply to the radio broadcast network points is provided from a transformer installed on the radio rack on the roof of building 3.
The audio loop and radio broadcast cable are made using a 1x2x1.5 KPKVng(A)-FRLS 180 cable
Cables and wiressystems are laid:
- in office and domestic premises without a false ceiling - in a 22x10 cable channel;
- according to the provided cable-supporting structures in the SCS section of this project;
- in rooms and corridors with a false ceiling - in a PVC pipe with a diameter of 20 mm;
- through partitions and interfloor ceilings to a water and gas pipe with a diameter of 25 mm;
All electrical networks of buildings can be divided into 2 large categories - high-current and low-current. Power electrical networks carry alternating voltage in the range from 220 to 380 V, as well as current from 1 ampere and above. These wires are important for office equipment and other equipment.
However, this equipment will not make any sense if clear information interaction of all office equipment is not organized, and its integration into a certain structure (branches, communications, Internet, etc.) is not ensured. It is this task that is performed by low-current systems, which differ from power systems by lower voltage in the network. As a rule, this voltage does not exceed 24 V, but in reality systems with voltages up to 60 V are considered low-current.
Low-current systems differ from power systems by one more factor - the high concentration of “information flow”. For a company ordering low-voltage work, it is very important to provide for all functions in advance, laying them out at the design stage. Perhaps while the company is not yet so large, there will be no need for some of these functions, but they will definitely be in demand as the organization develops. Taking into account all functions will allow the company to save its financial resources, since their subsequent integration into an already installed system will cost the company an order of magnitude more than the initial one.
Low-current systems include:
- Telephone communications.
- Structured cabling networks (equipment necessary for the operation of local computer networks).
- Security and fire alarms.
- Internet access.
- Video surveillance system.
However, if desired, low-current systems can provide several additional functions, including:
- Devices designed for negotiations - intercoms, selectors and automatic telephone exchanges.
- Energy resource management systems, as well as automated accounting systems.
- Access control and management systems (card readers, electronic locks, barriers, gates and turnstiles).
The use of low-current systems significantly facilitates the control and management of the most important processes in the company, and also improves the transfer of information. They can be used for a very long time without requiring replacement or modernization. At the same time, each company always has the opportunity to increase some elements of the CC without resorting to making changes to current systems.
Even though installation costs are required for the CC, in the long run these investments are worthwhile, and the positive results from using the CC are felt already in the first days after the installation is completed.
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.
SCS
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.