Overview
As communications technology and the rapid development of information industry, intelligent building (IB, Intelligent Building) in more and more use of computers, control equipment and communications equipment, all equipment on the building, voice switching, data terminals, network equipment, Video Equipment, HVAC, fire systems, security monitoring, power systems and thermal systems for intelligent management and control, to exchange information, share resources. So many systems and equipment, the information types and information distribution complex and variable, it is necessary to establish an effective wiring systems, the different control equipment, switching equipment, network devices and interconnect the computer equipment.
Network is connected to a separate device, and enable them to share information and resources links. Correct design and implementation of a communication network system can improve the speed and reliability, enabling a system work much easier for rich Xiaoshuai. Network construction should meet the published national and international standards, and should be able to change according to business requirements continually evolve and upgrade.
With the extensive use of computers, there is growing concern about the topic of networking and cabling. In the past, desktop computers usually work independently, and now the situation has changed. There are over 50% of the commercial computer connected to the LAN, they can greatly improve efficiency. LAN computers can be connected with servers and peripherals, or as sensors, cameras, monitors and other electronic devices signal path. If these links are temporary basis for the foundation, then, the work area will be filled soon Jiu Liao Gezhongwufa identify Di cable, permit their troubleshooting and maintenance is almost impossible.
Wiring ready
Anything before the implementation needs to be fully prepared. Wiring system involves the preparation of load assessment and planning, objectives and specifications of the life cycle factors.
1. Load assessment and planning
Type of network and cable choice is mainly need to connect the device type, their location and they used to decide. Start planning earlier, given the potential load on the network description is necessary. When a network needs to service multiple systems, mixed data traffic should they carefully consider the peak.
2. Target life cycle
Cabling system, the average target for the 15-year life cycle, with the major refurbishment of the building cycle is the same. During this time, the system's computer hardware, software and usage will be significant changes. Network throughput, reliability and security requirements would certainly be increased.
3. Technology development of indicators
Use; the number of users and potential growth; the user's location and the longest distance between them; the user the possibility to change position; with the current and future computer and software to connect; cable wiring of available space; network owner The total investment; regulations and safety requirements; to prevent service loss and the importance of data leaks
Wiring options
1. The importance of cabling system
Any network cabling is a key component of the system, so policy makers must be prepared to network 10% of the total investment for this area. High-quality cabling and network design investment is value for money.
2. Cable Choice
Connected to the network device type and communication cables carrying the load on the cable is a key factor in selection. In the wiring system should first determine the use of shielded cable, unshielded cable, optical cable, or use them together.
Cable typically used with the wire insulation and use one or more layers of plastic jacket. Cable is usually from 2 to 1800 line pairs. Large number of cable typically used on the backbone cabling system, they are especially suitable for low-rate voice and data applications.
3. Length
These cables in the trunk and the level (hub to the desktop) cabling system applications, the maximum length in the international standard IS0/IECIS11801 in detail.
4. Size limits
In determining the type of cable before the cable alignment checked the available space is also very important. Size, weight and flexibility of shielding depends on such factors as whether the use of metal foil or cable jacket preparation, and the number of wire cable used.
5. UTP Cable
Unshielded twisted pair (UTP) or higher in 622Mbps transfer rate on the transmission of data. This makes it possible to only use the original application of shielded cable to use this cheaper, smaller cable. UTP cable through the cable more closely matched on to reduce EMI interference. This cable is called a balanced circuit.
6. Balance circuit
In an ideal balance of the circuit, conductor, and the introduction of the noise voltage is zero, so that signal transmission between the lines on there will be no interference. However, this ideal can not be completely achieved, the cable signal to noise ratio (SNR) is used to measure the noise signal in the presence of cable in the case of signal quality indicators.
Because of shielding shielded cable, so its poor balance of properties, so good shielding integrity and a good grounding of the shielded cable is very important. High-quality UTP cable without the need for grounding or shielding the entire circuit does not require the case to achieve a good balance circuits. As the optical signal transmission through the light, so it is not any form of electromagnetic shielding effect.
7. Cable Choice
The transmission rate requirements and the needs of more than 155Mbps longer distance applications, the fiber is usually the best choice. Fiber is small, durable, etc,
But it's more expensive than other types of cable to be high. In most networks, cable is generally used as the trunk, while the use of UTP cable to act as a standard cable.
For those due to the installation time, space or other constraints is not easy to install cable systems, wireless local area network can be an alternative solution.
Installation planning
Most cable companies for their products provides 15-year shelf life. During this time, change is inevitable, but also can not be accurately predicted. The only solution is to design networks to meet the network requirements change and growth plan accordingly.
1. Future investment protection
Under normal use conditions, the new network should not be in the 15-year cycle limit building renovations to upgrade the system. The cabling system is designed to withstand more than most of the LAN transmission rate of 10 to 15 times the data traffic. This will allow the system without changing the wiring of the circumstances under the new network technology.
2. Generic cabling systems
The main advantage of generic cabling system is that users can use it access network equipment from different vendors. At the same time, it also allows users to run on the same cabling network of several independent systems. For example, users can set up a telephone wiring system, computer and environmental control systems.
3. Structure Cabling
Universal wiring and cabling mass are the core of structured cabling, Lucent Technologies (formerly AT & T) and its SYSTIMAXSCS solution is a pioneer in this area. It uses an open structure platform that supports all the major private networks and non-dedicated network standards and protocols. SYSTIMAXSCS using UTP cable and fiber optic cable as a transmission medium, using star topology, using a standard socket for termination. SYSTIMAXSCS type of cable used in simple network of modular, does not affect users in the case of the network can easily be extended or changed.
4. Network components
Each building or buildings located within the patch panel is used to achieve the computer, peripherals, network hubs and other equipment or the withdrawal of fast access network components. In the structure and layout of the ongoing adjustment of the company, it can save a lot of cost. ----
Avoid interference
Each active electronic and electrical equipment could produce electromagnetic interference to disrupt network communications. With the increased use of electronic devices, this problem has become more prominent. Cables and cable wiring in the choice of consideration, how to prevent EMI interference for the protection of communication is also a very key issue.
There are two ways to measure the performance of cable crosstalk: crosstalk between lines and PowerSum on crosstalk. Line of the crosstalk between the cables is used to measure the center line of the maximum interference generated by the situation.
1. PowerSum
PowerSum reflect a more realistic crosstalk interference. It is multi-pair cables have all the lines on the signal transmission method of measurement. The cable center line on the number of more than four pairs of cable, PowerSum is the only one that can correct method of testing crosstalk performance.
2. SNR
In the system used to measure inhibition of the EMI interference indicator is the signal to noise ratio (SNR). Network, the higher signal to noise ratio, the network data transmission error occurs the less the risk.
3. Cable alignment
Including connectors and patch panels, including all network components, you must have some measures against EMI interference. When using the products from different manufacturers build the network, this is especially to be noted.
Design and Installation
Adopted in determining the type of network configuration and cables, the remaining work is to carry out specific system design and installation. The first step should be to determine the structure of the network, usually this is a relatively straightforward task.
1. Route folding
The typical structure of the network may be different. For example, the trunk can be used folded structure, so the servers, hubs and patch panels placed in a tight focus on security in the region, this can save space and improve the system's physical security.
2. Redundancy
If the system is used to perform critical tasks, then the system may need to use multiple lines to achieve the mesh network design, the system has a certain degree of redundancy.
3. Physical limitations
An earlier stage in the planning of the route has been chosen in the horizontal cabling and wiring used in cable mass type. In the installation, design and planning stage, the choice of cable type to consider its physical limits is very important.
4. Cable alignment
Cable companies will give the minimum bend radius and maximum cable tension and other indicators, such as the heat source they will also, EMI interference and other issues related to the reference given proposal. What networks can share and other pipelines, particularly in places where electricity distribution cable, EMI problems should be special attention.
5. Alignment chart
Installed in the wiring system must be prepared before taking a complete cable line graph. It installed very helpful staff, while maintaining the network for future expansion and troubleshooting is also a great reference value.
6. Cable identification
Chart and the actual label on the cable should be cross-referenced. Planning and identification of the work by the installer or interior systems division to complete. There are many packages to help people to complete this work.
7. Installation and access
Network design should follow the principle of easy to install and access, and cable should be considered for adequate support and protection. Guidelines for the application vendors should be designed to ensure that its products meet these requirements, they should also take into account the cable pipeline with relevant national and international standards, on-site installation personnel have the responsibility to ensure that it meets building code requirements and standards requirements. Choice of cable support and protection methods include: underground pipe; activities of the floor; cable channels; tray and trunking; ceiling wiring; border crossings.
8. Pipe and ceiling wiring
Pipe and ceiling wiring is usually common standards should be implemented. For example, in EIA/TIA569, the provisions of the pipeline's maximum length of 30m, and the cable drag point of 90 ° bend should be less than the number of two. Pipe bending radius of the internal pipe diameter must be 6 times larger than 50mm in diameter pipeline for the bending radius should be at least 10 times its diameter.
9. Line channels
During cable installation, use the appropriate equipment and procedures can reduce the cable tension and to avoid cable damage. System installation, to be followed line channels and pipes manufacturers guidelines given in the encoding requirements of cable channels filling patterns.
10. Cable support
Ceiling wiring, piping, trays and other pipeline hardware to be used in the ceiling above the ceiling. In addition, the cable does not exceed 1.5m high in space, you can use the J-hook, ring or other means to do cable suspension support. In addition to the design of specialized outside, do not use ceiling tiles, brackets and supports to fix the cable, nor can communications cable and power cable tied to a fixed communication cables.
11. Cable to the desktop
The last part of the network connection may include office furniture, house or wiring under the carpet. Cable last traces of permanent buildings house the network access point adapter may be a potential weak link in the network.
12. Network socket
The end of each network is a socket, the user can use the jumper connected to the device and network. Socket location, quality and fixed hardware in the network design is a very important part. CENELECprEN50174 and EIA/TIA569 standards on the installation on walls, floors and furniture in the outlet position with the relevant requirements. In addition to the standard provisions of the principles, the patch's convenience should also be fully considered.
13. MDF
Does not change in a reliable network, is the need to use patch panel. In fact, each network are constantly changing, it is patch panel allows people to more quickly and easily achieve the network changes. MDF also allows the network to find and eliminate errors easier.
Investment costs
In determining the network installation and supply tenders, the network owner's total investment cost is a key factor. As the routing network has at least 15 years of life, so the network's operating costs and upgrade costs will equal or exceed the initial investment amount. After the network is installed, add, remove and change the device connected to the network usually requires a large investment.
1. Temporary wiring options
Alternative integrated structured cabling system is a temporary wiring system. It has different forms, some of which are also defined as the structured cabling areas, but they can not be called an integrated structured cabling. In the temporary wiring system can use different types of cabling components to achieve system function, but may require higher costs, and may often lead to communication failure occurred.
2. Compatibility
Temporary wiring system maintenance costs are very high, since the new parts must be purchased from multiple suppliers, which will require additional overhead, while there is also the risk of incompatibility between the components.
3. Network failure
Operation failure may be greater potential problem, and is the worst predictions. Poor quality in the design and implementation of the network to find the error is very difficult and costly piece of work. Complete line documents and on cable and connectors for easy access to the maximum extent possible to help maintain smooth progress.
4. Quality Assurance
Warranty is to protect the quality of network system failures will not lead to accidental loss of the best guarantees. In the ideal case, cable wiring system and all parts of the shelf life should be 15 years. Network design and implementation should be authorized by the manufacturer company, the components used in its quality assurance also should beyond question. This project future problems much less likely to.