Construction technology of integrated wiring system

Construction technology of integrated wiring system

7.1 Key points of construction technology of integrated wiring project

7.1.1 Preparation work before the start of the wiring project

1. Environmental conditions and construction preparation before construction

1. Familiar with and fully understand the design documents and drawings

(1) Read the engineering design documents and construction drawings in detail, and check the main contents, such as the design description, construction drawings and engineering budget estimates, with each other and carefully check each other.

⑵Cooperate with the design unit, check the construction drawings on site and carry out installation and technical disclosure. The design unit has the responsibility to introduce the main design intent and various factors of the design documents and construction drawings to the construction unit.

Conclusion: Design the actual construction drawing of the integrated wiring. Determine where the wiring goes. For use by construction personnel, supervisors and supervisors. Design the actual construction drawing of integrated wiring

2. Preparation

(1) Cables, sockets, information modules, connectors, regulated power supplies, etc. used for project construction shall be implemented by the purchaser and the date of delivery shall be determined.

(2) Various wire ducts, accessories and related wiring materials used in project construction should be in place before starting construction;

(3) If the hub is a centralized power supply, prepare wires, iron pipes and formulate safety measures for electrical equipment (the power supply line must be carried out in accordance with the standards and standards of civil buildings).

3. On-site investigation of the construction conditions of the engineering environment

â‘´Because most of the cables of the integrated wiring system are laid in a concealed manner.

⑵In the field investigation, it is necessary to check whether the designed cable laying route and equipment installation position are correct and appropriate, whether there is enough space for installation construction or need to take remedial measures or change the design plan.

(3) For special rooms such as equipment and mainline transfer rooms, the environmental conditions and construction techniques must be investigated and inspected.

4. Preparation of installation progress schedule and construction organization plan

It is required that the installation and construction plan must be detailed, specific, rigorous and orderly, so as to facilitate supervision and implementation and scientific management.

Develop a construction schedule (with appropriate room, unexpected things in the construction process may occur at any time, and require immediate coordination).

2. Inspection of equipment, equipment, instruments and tools

1. General requirements for equipment and equipment inspection

(1) Before installation and construction, conduct detailed inventory and sampling tests on the equipment.

⑵ The models, specifications, programs and quantities of the main equipment required in the project should meet the design requirements.

(3) The number of cables and main equipment must meet the requirements of continuous construction.

â‘· Main equipment after inventory, inspection and sampling test shall be recorded.

2. Specific inspection requirements for equipment and equipment

â‘´ Cable inspection requirements

⑵ Inspection requirements for wiring connection equipment

(3) Inspection requirements for plug-in components

â‘·Inspection requirements for profiles, pipes and iron parts

3. Instrument and tool inspection

(1) Inspection and requirements of test instruments

The test instrument should be able to test various electrical properties of symmetrical cables of category 3, 4 and 5 twisted pairs. It is considered according to the requirements of second-level accuracy specified in TIA / EIA / TSB67. Pay attention to the safety of precision instruments during handling.

⑵ Inspection of construction tools

During the preparation of the tools, you should consider them carefully. Each situation may occur. There are many tools used, so I will not list them here.

3. Submit the start report to the engineering unit.

7.1.2 Matters needing attention during construction

1. Site construction

On-site construction adopts the project manager responsibility system.

Project manager: organize various departments to conduct on-site technical analysis, technical briefing, and personnel arrangement;

Technical Department: Responsible for technical communication, on-site technical guidance, and organization to solve technical problems;

Construction Department: carry out on-site construction, wiring construction, card wire and equipment installation;

Quality inspection department: responsible for construction quality and acceptance.

2. The construction specifications are strictly in accordance with the construction requirements of the integrated wiring system.

3. The construction schedule strictly controls the construction schedule and guarantees the construction cycle.

4. Quality management and measures

Promote a comprehensive quality management system according to the characteristics of the project, formulate various management plans to be implemented and pay for implementation, achieve organization, system, and various data at all stages of construction to improve the quality of the project to a new level.

The specific measures are as follows:

1) Quality assurance measures

● Strengthen internal management, implement special quality responsibility systems, and establish a leadership system guided by company engineers and project managers responsible for quality inspections.

● The project manager organizes all professional team leaders to make technical preparations for the start of construction. Each professional technical team prepares the implementation steps of the sub-division and sub-projects according to the design plan, construction drawings, construction rules and specific conditions of the project, and clarifies the tasks to the team.

● Strictly follow the construction according to the drawings and strictly abide by the process operation regulations.

● Each team should ensure the overall quality of the project with the quality of each process, and each team leader must conduct on-site supervision and inspection of the responsible professional process.

● The materials and equipment used in the project must meet the qualified quality standards and have a certificate of conformity or material certificate. Unqualified materials and equipment shall not be sent to the construction site.

● The measuring tools used in the construction must be approved instruments, the measuring must be accurate and the instruments are sensitive to ensure the quality requirements.

● On-site construction personnel must accept the inspection and supervision of Party A and the quality inspection personnel at all levels. When quality problems occur, they must be reported in time and corrective measures should be proposed to implement them layer by layer.

2) Safe and civilized construction measures

● Establish an on-site management team with project managers as the team leader and various professional team leaders to take charge of on-site management, supervision and coordination.

● The professional team leaders conduct on-site investigations before construction, formulate safety measures based on the on-site conditions, and clarify the precautions during construction.

● The on-site leadership team regularly conducts safety and civilized construction inspections, and promptly corrects any problems found.

● On-site workers should be equipped with effective labor protection equipment to ensure the lighting and communication conditions of the construction environment.

● Achieve civilized site construction, take necessary anti-theft and anti-pry measures, and strive to be a civilized construction team.

3) Saving measures

● Accurately calculate construction materials, implement limit picking, and plan well to reduce material losses.

● Do a good job in the use and maintenance of machinery and equipment, strengthen the management of equipment stagnation time and machinery failure rate, reasonably arrange personnel to enter the field, strengthen labor discipline and improve work efficiency.

● Do a good job in the management and protection of the completed work, to avoid damage to the completed work due to improper protection, resulting in repeated construction.

● Pay close attention to the inspection of completed projects and the collection and sorting of engineering materials, drawing of working drawings, and close up of project closures to reduce management expenses.

● Strengthen the management of the use of instruments and tools, according to the work team to implement the special person responsible, so as not to cause loss or damage and affect the construction period.

5. Matters that Party A needs to cooperate

(1) Provide an office equipped with power supply as a duty and office for the construction site.

(2) Provide an empty room as a construction material and tool storehouse.

(3) Go through various procedures for the construction personnel to enter the site; two days before the construction, clean up the items on the wiring position of this layer, do not hinder the construction, keep important items and materials well; leave keys in each room during the construction period to facilitate the construction Easy access for personnel.

(4) Provide precautions and provide access locations for wiring routes, such as suspended ceilings and floor pits.

(5) Provide specific locations of other important lines to avoid touching these lines during construction.

(6) For the purpose of doing a good job in the wiring project, actively cooperate with the construction personnel to make the project proceed smoothly.

6. Specifications that should be strictly observed during the construction of integrated wiring

● ORTRONICSSCS comprehensive wiring system construction specifications;

● China Building Electrical Design Code;

● Communication design specifications for industrial enterprises;

● China Engineering Construction Standardization Association Standards;

● General rules for design of structured wiring system;

● Technical specifications for construction and acceptance of telephone line engineering.

7. Related international standards and national standards

● ANSITIA / EIA-568-A telecommunications wiring standard for commercial buildings;

● TIA / EIA-569 commercial building standards on telecommunications routing and space requirements;

● TIA / EIA-570 lighting, residential and light industrial building wiring standards;

● TIA / EIA-606 wiring closet management;

● TIA / EIA-607 shielding and grounding;

● ISO / IEC11801 commercial building telecommunications wiring standard;

● EN / 50173 European commercial building telecommunications wiring standard;

● TIA / EIATSB-67 test standard;

● People's Republic of China Building Integrated Wiring Standard "Code for Design of Building and Building Group Integrated Wiring System";

● People's Republic of China industry standard "Design Standards for Telephone Communication Facilities in Urban Residential Areas and Office Buildings";

● CCITTISDN integrated service data network standard;

● IEEE802.310Base-T network standard;

● IEEE802.5TokenRing network standard;

● ANSIFDDI100Mb / s optical fiber distributed data interface high-speed LAN standard;

● ATM155 / 622Mb / s asynchronous transmission mode standard;

● RS-232, X.25, RS-422 asynchronous and synchronous transmission standards;

● China Building Electrical Design Code;

● Communication design specifications for industrial enterprises.

7.1.3 Construction safety of integrated wiring project

The following safety points should be followed during construction:

● Wear proper tooling; ● Remember safety when planning work; ● Ensure the safety of the work area; ● Ensure that the power line is in the correct position; ● Use appropriate tools.

1. Wear the right tooling

Wearing proper tooling can ensure safety at work. In general, overalls, shirts and jackets are enough. In addition to these garments, the following accessories are required in certain operations:

(1) Safety glasses. (2) Hard hat. (3) Gloves. (4) Labor protection shoes.

2. Remember safety when planning work

If you find safety problems in the relevant work area when planning work, you can ask the person in charge of the project to check and solve them together.

3. Keep the work area safe

Ensure the safety of everyone in the work area. Once the project is determined, safety belts and safety signs should be set up in the entire wiring construction area, and various construction tools should be properly arranged to prevent them from hindering others. The lack of management tools is harmful. Security risks.

4. Use the right tools

Pay attention to the following points when choosing:

● Ensure that the tool is sharp; ● Repair the screwdriver so that its head fits the screw cap; ● Use double insulated power tools where power tools are needed; ● Make sure that the tools are in good condition; ● If the tools are worn out, replace them.

7.1.4 Tools used in the construction of integrated wiring works

Several common tools will be used during the construction of the integrated wiring project. The following lists some necessary tools:

● pipe lock pliers; ● oblique nose pliers; ● drill (1/4 and 1 / 2in drilling depth); ● drill; ● power-on tester; ● hacksaw; ● flat nose pliers; ● screwdriver (flat head and cross flower ); ● Slate saw; ● Rod; ● Wire cutter; ● Multi-purpose knife; ● Rope or pull rope; ● Impact tool; ● Cable clamp; ● Cable bracket (if using reel cable).

7.1.5 Test

During the construction process, the entire project should be tested to ensure the quality of the project. Test task:

● Test the connectivity between the workroom and the equipment; ● Test the connectivity of the trunk line; ● Test the performance parameters such as information transmission rate, attenuation rate, distance wiring diagram, and near-end crosstalk.

7.1.6 Attentions at the end of project construction

At the end of the project construction, attention should be paid to the following work:

(1) Clean up the site and keep the site clean and beautiful;

(2) Repair junctions such as wall holes and shafts;

(3) Collect all kinds of surplus materials, put the surplus materials in one place, and register the quantity that can be used;

(4) Make summary materials.

The summary materials mainly include: construction report; wiring engineering drawing; construction process report; test report; use report; acceptance report required for project acceptance.

7.2 Power supply of integrated wiring system

1. Selection of load level

It should be considered based on factors such as the use nature, importance, work characteristics, and communication security guarantee of the intelligent building.

2. Power supply

The three-phase four-wire system is adopted, the single-phase rated voltage (phase voltage) is 220V, the three-phase rated line voltage is 380V, and the frequency is AC 50Hz.

3. Power supply and distribution

Generally, there are the following power supply and distribution methods:

(1) When the intelligent building is a type of power supply unit, the power supply is very reliable, the surrounding environment is good and there is no electromagnetic interference, you can consider the direct power supply mode to reduce the number of equipment and save engineering investment.

(2) If the intelligent building and the intelligent community have two or more AC power sources, the power supply equipment that can automatically switch should generally be selected.

(3) The most commonly used in integrated wiring system is the combination of direct power supply and uninterruptible power supply system (UPS), that is, the municipal power directly supplies power to the auxiliary equipment in the equipment room and the computer room, and the program-controlled user telephone exchange and computer Both the host computer and the interconnected equipment of the network system are powered by an uninterruptible power system (UPS).

(4) When the program-controlled user telephone exchange and computer host are installed in the equipment room, the specific content and design requirements of the power supply design should be considered in accordance with the "Industrial Enterprise Program-controlled User Switch Engineering Design Regulations" or the relevant provisions of the computer host power requirements.

(5) In order to ensure the normal operation of the integrated wiring system, an independent, stable, and reliable 220V, 50Hz AC power supply should be provided in the equipment room and management area for maintenance, overhaul, and daily management.

(6) In order to avoid electromagnetic interference and external radiation, the power line should be shielded through metal pipes after entering the equipment room.

7.3 Routing technology

For an experienced installer, "I would rather use an additional 1000m cable than an additional 100 man-hours", usually the cable is cheaper than the labor cost.

1. Understand the structure of the building

For the wiring construction personnel, it is necessary to thoroughly understand the structure of the building. Since most of the cables are routed under the floor or in the ceiling, designers must understand the situation in the floor and suspended ceiling clearly. That is to say, it is necessary to know exactly where the wiring can be made and where it is not easy to wire, and make an explanation to the user.

The installer should know the following typical pipeline structures:

● raised floor (elevated, computer); ● equipment system; ● insulated wall; ● brick wall; ● through; ● spline ceiling; ● hanging shed; ● underfloor duct; ● arched shed; ● with connecting outlet duct wall.

2. Check the pull (traction) wire

Before installing any type of cable in an existing building, you must check for the presence of cables. The pull wire is some kind of string, which is placed along the route (pipe) where the cable is to be routed, and must be the full length of the route. The vast majority of pipeline installers have to leave a cable for the subsequent installers to make it easier to route the cables. If not, consider the wiring problem.

3. Determine the location of existing cables

If the wiring environment is an old building, you must understand how the original cables are routed, what pipes (if any) are used, and how these pipes go. Knowing this will help to establish routes for new cables. In some cases, the original route can be used.

4. Provide cable support

According to the installation situation and the length of the cable, you should consider using the bracket or the hanger slot, and decide the bracket hanger according to the actual situation, so that the quality added to the structure will not be overweight.

5. Wire speed considerations

The speed of pulling the cable theoretically speaking, the smaller the diameter of the wire, the faster the speed of pulling the wire. However, experienced installers generally take a slow and smooth cable pull rather than a fast cable pull, because fast cable pull often causes the cable to become tangled or tripped.

6. Maximum pull

Excessive tension will cause deformation of the cable, which will cause a drop in cable transmission performance. When routing, the tension that the cable can withstand should be considered. The maximum allowable tension of the cable is as follows:

â‘´ The maximum allowable pulling force of one 4-pair cable is 100N;

⑵ The maximum allowable tension of two 4-pair cables is 150N;

⑶ The maximum allowable pulling force of three 4-pair cable is 200N;

⑷ The maximum allowable pulling force of n wire cables is n × 50 + 50N;

⑸ No matter how many pairs of cables, the maximum tensile force cannot exceed 400N.

7.4 Laying technology

Types of materials used for wire grooves: divided into metal grooves, pipes, and plastic (PVC) pipes.

From the perspective of the distribution of troughs, it is divided into working room trunking, horizontal trunk trunking, and vertical trunk trunking.

What kind of material is used depends on the user's needs and investment.

7.4.1 Laying of metal pipes

1. Processing requirements of metal pipes

(1) In order to prevent the cable from being scratched when the cable is worn, the nozzle should be free of burrs and sharp edges.

(2) In order to reduce the shear force on the cable at the nozzle of the directly buried pipe when it is subsidence, the metal nozzle should generally be made into a trumpet shape.

(3) After the metal pipe is bent, there should be no cracks and obvious dents.

(4) The bending radius of the metal tube should not be less than the minimum allowable bending radius of the cable inserted.

(5) Anti-corrosion paint should be applied to the peeled zinc layer of galvanized pipe to increase the service life.

2. Metal pipe cutting thread

When piping, the pipe should be cut according to the actual required length. The pipe can be cut with a hacksaw, pipe cutter or electric pipe cutter. Gas cutting is strictly prohibited.

Metal pipe threading: the connection of the pipe and the pipe, the connection of the pipe and the junction box, the wiring box, all need to be piped at the end of the pipe. Welded steel pipe threading can use pipe stranding plate (commonly known as substitute silk) or electric threading machine. For hard plastic pipe thread, round wire plate can be used.

When threading, first fix the tube tightly on the tube pressure, and then thread the tube. If electric threading machine is used, work efficiency can be improved. After finishing the wire, the pipe mouth should be cleaned at any time, and the burrs on the end face and the inner wall of the pipe mouth should be filed with a file to keep the pipe mouth smooth to avoid cutting the cable insulation sheath.

3. Metal tube bending

When laying metal pipes, elbows should be minimized. There should be no more than 3 elbows for each metal tube, and no more than 2 right-angle elbows. There should be no S-bends.

Bending tools for metal pipes: generally use pipe benders.

Method: First put the front part of the pipe to be bent in the pipe bender, and place the weld seam on the back or side of the bending direction to prevent the pipe from bending flat, then step on the pipe with your feet, pull the pipe bender by hand to bend, and gradually Move the pipe bender so that the required bend can be obtained.

The bending radius should meet the following requirements:

(1) When it is fitted, it is generally not less than 6 times the outer diameter of the metal pipe; when there is only one bend, it should be not less than 4 times the outer diameter of the metal pipe; the whole row of metal pipes is best bent into a concentric circle at the turning point.

⑵When concealed, it should not be less than 6 times the outer diameter of the metal pipe; when laying in the underground or concrete floor, it should not be less than 10 times the outer diameter of the metal pipe.

● When the pipe is not bent, the length can reach 45m; ● When the pipe has 1 bend, the straight line length can reach 30m; ● When the pipe has 2 bends, the straight line length can reach 20m; ● When the pipe has 3 bends, the straight line length can be Up to 12m; ● The mouth of the concealed pipe should be smooth and with insulating sleeve, and the protruding part of the mouth should be 25-50mm.

4. Connection requirements for metal pipes

The connection of the metal pipe should be firm and well sealed, and the two pipes should be aligned.

There are usually two methods for the connection between metal pipes: short sleeve connection and pipe joint thread connection.

The length of the short sleeve or threaded pipe joint shall not be less than 2.2 times the outer diameter of the metal pipe. When the metal pipe is connected by a short sleeve, the construction is simple and convenient; the threaded connection of the pipe joint is more beautiful and can ensure the strength of the metal pipe after connection. No matter which method is adopted, it should ensure that the metal pipe nozzles to be connected are aligned, firm and sealed.

After the metal pipe enters the junction box of the information socket, the buried pipe can be fixed by welding, and the exposed length of the pipe entrance into the box should be less than 5mm. It is obvious that the tube should be fixed with a lock nut or a cap, and the screw buckle exposing the lock nut is 2 to 4 buckles.

5. Laying of metal pipes

(1) Concealed design requirements for metal pipes

● The inner diameter of the metal pipe pre-buried in the middle of the wall should not exceed 50mm, and the pipe diameter in the floor slab should be 15-25mm. When straight pipe is laid, the dark wire box should be generally set at 30m.

● The base of metal pipes laid in concrete and cement should be solid and flat, and there should be no subsidence to ensure the safe operation of the cables after laying.

● When connecting metal pipes, the nozzles should be aligned without any misalignment, the joints should be tight, and no water or mud can penetrate, so as not to affect the effective management of the pipeline, and ensure the smooth running of the cables.

● Metal pipes should have a drainage slope of not less than 0.1%.

● The buried depth of the metal pipes between the building groups should not be less than 0.8m; when laying under the sidewalk, it should not be less than 0.5m.

● Pull wire or pull wire should be placed in the metal pipe.

● Both ends of the metal pipe should be marked to indicate the building, floor, room and length.

(2) The pipes should meet the following requirements when exposed

The metal tube should be fixed with a clip, which is more beautiful and easy to disassemble when it needs to be disassembled. The spacing of metal support points shall be designed in accordance with regulations when required. When there is no design requirement, it should not exceed 3m. Fix the pipe with a pipe clamp at a distance of 0.3m from the junction box. At the place of the elbow, both sides of the elbow should also be fixed with pipe clamps.

(3) When laying the optical cable and cable in the same tube, the plastic sub-tube should be preset in the dark tube, and the optical cable should be laid in the plastic sub-tube to separate the optical cable and the cable.

7.4.2 Laying of metal trough

The installation of the wire channel should be synchronized with other pipelines (such as air ducts, water supply and drainage pipes) after the completion of the civil works, or it can be installed a little later than other pipelines. However, it should be avoided as far as possible after the completion of the decoration project, causing difficulties in laying cables.

Most metal bridges are made of steel plates with a thickness of 0.4 to 1.5 mm.

Features: (compared to traditional bridges), light structure, high strength, beautiful appearance, no welding, no deformation, novel connection style, easy installation, etc. It is an ideal supporting device for laying cables.

Metal bridges are divided into two types: slot type and ladder type. The trough type bridge refers to a trough-shaped part made of a whole steel plate; the trapezoidal bridge refers to a trapezoid-shaped part composed of sides and several crosspieces. The bridge accessory is used to fix or supplement the straight line and bend function components necessary for the connection between the straight line section and the straight line section and the bend. Supports and hangers refer to the components that directly support the bridge. It includes supporting arms, uprights, upright bases, hangers and other fixing brackets.

In order to prevent the corrosion of the metal bridge, the surface can be purified by electroplating zinc, baking paint, spraying powder, hot dip galvanizing, nickel-zinc alloy plating or using stainless steel plate.

Selection principle: According to the engineering environment, importance and durability, the appropriate anti-corrosion treatment method can be selected.

Generally, the environment with lighter corrosion can adopt galvanized cold-rolled steel bridge;

In a corrosive environment, nickel-plated zinc alloy purification treatment bridge can be used, or stainless steel bridge can also be used.

The performance of the cables used in integrated wiring has certain requirements on the environment. For this reason, a slotted bridge with a cover and no hole is often used in the project (referred to as the wire slot).

1. Installation requirements

The installation of the cable duct should be synchronized with other pipelines (such as air ducts, water supply and drainage pipes) after the civil works are basically completed, or it can be installed a little later than other pipelines. But try to avoid the installation after the decoration project, which will cause difficulties in laying cables.

(1) The installation position of the wire groove should meet the requirements of the construction drawing, and the left and right deviation depends on the environment, and the maximum does not exceed 50mm.

(2) The deviation of the level of the wire groove per meter should not exceed 2mm.

(3) The vertical wire groove should be vertical to the ground without tilting, and the deviation of the verticality should not exceed 3mm.

(4) A joint connecting plate is used for splicing between the trunk sections and the sections, and the screws should be tightened.

(5) When the straight section of the bridge exceeds 30m or crosses the building, there should be expansion joints, and the connection should use expansion joints.

(6) The turning radius of the wire groove should not be less than the largest of the minimum allowable bending radius of the cable in the groove.

(7) The cover of the wire channel should be fastened.

(8) The support and hanger should be kept vertical, neat and firm, without skew.

In order to prevent electromagnetic interference, it is advisable to use braided copper tape to connect the cable duct to the grounding device of the passing equipment room or floor wiring room, and maintain a good electrical connection.

2. Requirements for protection of cable laying support of horizontal subsystem

(1) Support protection requirements for embedded metal wire ducts

● When pre-buying the wire groove in the building, according to different sizes, at least one or two layers of equipment should be pre-buried, and the height of the wire groove section should not exceed 25mm.

● When the straight buried length of the wire trough exceeds 15m, or when there is a cross or change in the wire trough route, it is advisable to set a cable box to facilitate cable routing and maintenance.

● The box cover of the junction box should be able to open and be flush with the ground, and waterproof measures should be taken at the box cover.

● The wire channel should be introduced into the distribution box by metal pipe.

(2) Set the requirements for the protection of the wire channel support

● When laying horizontally, the support spacing is generally 1.5-2m; when laying vertically, the spacing of the support points fixed on the building structure should be less than 2m.

● When laying a metal trunking, set up a bracket or hanger under the following conditions: at the joint of the trunking; at a distance of 1.5 to 2m; at a distance of 0.5m from the two ports of the trunking; at a bend

● The distance between the fixed points on the bottom of the plastic trunking is generally 1m.

(3) When laying cables under the raised floor, the clearance in the raised floor should not be less than 150mm. If the raised floor is used as the air duct of the ventilation system, the clear height in the floor should not be less than 300mm.

(4) When a public post is used as a ceiling support post, cables can be laid in the post. The support point of the column should avoid the position of the groove and the wire groove, and the support should be firm.

(5) When the location of the information point in the work area and the cable laying method are undecided, or when the cable is laid under the carpet in the work area, it is advisable to set up transfer boxes. The service area of ​​each transfer box is about 80cm2.

(6) Different types of cables are placed in the metal wire slot, and should be laid in the same room (separated by metal plate).

(7) When using lattice floor slabs and trenches in combination, laying cables supports protection requirements

● Grooves and grid lines must communicate.

● The groove cover can be opened and is flush with the ground. Waterproof measures should be taken at the cover and the outlet of the information socket.

● The width of the groove should be less than 600mm.

3. Requirements for protection of cable laying support in trunk subsystem

(1) Cables must not be placed in elevators or pipeline shafts.

(2) There should be communication between trunk channels.

(3) The holes used by the cables in the weak current room through each floor should be square or round. The size of the rectangular hole should not be less than 300mm × 100mm. At least three round steel pipes should be installed at the round hole, and the diameter should not be less than 100mm.

(4) The cable laying support protection of the trunk subsystem of the building group should meet the design requirements.

7.4.3 Laying of PVC plastic pipes

PVC pipes are generally buried in the working area, so pay attention to two points during operation:

● When turning the pipe, the bending radius should be large to facilitate threading. ● It is not advisable to thread too much in the pipe, and more than 50% of the space must be left.

7.4.4 Laying of plastic tank

There are many specifications of plastic tanks, and their laying is similar to metal tanks in theory, but the operation is different. There are three ways:

● Booms or bracket bridges are placed on the ceiling; ● Bridge bridges are laid outside the ceiling; ● Brackets and fixed grooves are used outside the ceiling.

When using a bracket, generally install a bracket around 1m. When the fixing groove is used, the fixing point is generally installed around 1m. The fixed point refers to the place where the groove is fixed. According to the slot size:

(1) For a slot with a size of 25mm × 20mm ～ 25mm × 30mm, 2 to 3 fixing screws should be arranged at a fixed point and arranged horizontally.

(2) For a groove of 25mm × 30mm or more, one fixed point should have 3 to 4 fixed screws, arranged in a trapezoid shape, so that the stress points of the groove are distributed.

(3) In addition to the fixed points, two holes should be drilled every 1m or so and penetrated with twisted pairs. After the wiring is completed, bundle the twisted pairs.

The horizontal trunk line and vertical trunk line layout methods are the same, the difference is that one is a horizontal distribution groove and the other is a vertical distribution groove.

At the junction of the horizontal trunk line and the work area, when it is not easy to construct, metal hose (snake skin tube) or plastic hose can be used for connection.

7.4.5 Calculation method for selection of slot and tube sizes

According to the experience of project construction, the following simple methods can be adopted for the selection of grooves and pipes:

Among them: n: the number of cables (known number) to be installed by the user; the cross-sectional area of ​​the groove (pipe): the cross-sectional area of ​​the groove pipe (unknown number) to be selected;

Cable cross-sectional area: the selected cable area (known number); 70%: the space allowed by the wiring standard;

40% to 50%: wasted space between cables.

7.5 Design technology of wiring cable tray

The weak current system of the intelligent building is usually composed of multiple corresponding information monitoring and communication facilities and other corresponding systems, such as BA (building automation), OA (office automation), CA (communication automation), etc., and determine its function according to the functional requirements of the main body of the building Level and content.

Due to the parallel crossing of various pipelines in the building and the limited space, especially in large office buildings, financial commercial buildings, hotels, venues and other buildings, the information points are dense, so in addition to the use of floor trenches and buried pipes in the walls, cable laying is in the shaft Cable bridges are widely used in the ceiling of the house to provide wiring in different directions.

7.5.1 Bridge structure

The cable bridge is divided into trough type, tray type and ladder type structure, which is composed of bracket, support arm and installation accessories. When selecting the model, you should pay attention to whether all the components of the bridge meet the requirements of series, generalization and standardization.

7.5.2 Bridge load and load characteristics

1. Load of cable tray

The load of the cable bridge is divided into static load, dynamic load and additional load.

Static load refers to the weight of the cable laid in the cable bridge. Generally, we use the type of cable, the number of cables, and the weight of each cable to reflect the size of the static load according to the routing of the cable in the bridge.

Q use = q1 + q2

Among them: q1: the uniform load of the cable (the maximum value of the uniform load of each layer) (kN / m2), the uniform load is the load of the pallet, ladder frame or cable tray;

q2: When laying or repairing the cable, the equivalent uniform load of the weight of the construction maintenance personnel (kN / m2).

7.5.3 The expansion and contraction of the bridge

Due to changes in ambient temperature, the steel cable bridge will expand and contract. The outdoor bridge is greatly affected by temperature. For example, if the maximum ambient temperature is 40 ° C and the minimum temperature is -20 ° C, the maximum shrinkage of the cable bridge is calculated as follows:

from that we get:

When the temperature difference is 60 ℃, Δι = 0.672mm / m;

When the temperature difference is 50 ℃, Δι = 0.560mm / m;

When the temperature difference is 40 ℃, Δι = 0.448mm / m.

Expansion joints should be considered in the cable tray of the straight section in engineering design. The spacing of the expansion joints is recommended to be determined as follows:

● 50m when the temperature difference is 40 ℃;

● 40m when the temperature difference is 50 ℃;

● 40m when the temperature difference is 60 ℃.

7.5.4 Grounding of the bridge

In the construction of wiring projects, the galvanized cable bridge must be well grounded.

(1) The contact resistance of each fixing bolt of the direct plate of the galvanized cable bridge should be less than 0.005Ω. At this time, the cable bridge can be used as a grounding trunk (the powdered cable bridge should not be used as a grounding trunk). Formula calculation:

Among them: ρ = 15 × 10.6Ω · cm (at 20 ℃); L: length, calculated as 100mm; S: cross-sectional area (cm2).

(2) When the cable bridge is installed and connected as a whole, the resistance of each ladder edge (or each cable slot) is

Among them: R: ladder resistance, that is, the total resistance (mΩ) of the entire length of the (cable channel); r: resistance per unit length of the ladder (mΩ / m); r ': contact resistance of the direct plate fixing bolts.

7.5.5 Bridge frame design and installation requirements

(1) Determine the direction.

(2) Load calculation.

(3) Determine the width of the bridge.

(4) Determine the installation method.

(5) Draw a flat and sectional view of the cable bridge.

In addition, there are other installation requirements:

(1) When the cable tray enters the building from the outside, the outward slope of the cable tray shall not be less than 1/100.

(2) The clear distance between the cable bridge and the electrical equipment is not less than 0.5m.

(3) When two sets of cable bridges are laid in parallel at the same height, the clear distance between them is not less than 0.6m.

(4) Draw the route of the bridge on the parallel map, and indicate the coordinates or positioning dimensions and elevation of the starting point, end point, turning point, branch point and lifting point of the bridge.

(5) Bridge support points, such as uprights, support arms or non-standard supports, frame spacing, installation methods, model specifications, and elevation, can be listed on the plane, or can be marked out in sections, with different cross-sections, single lines Figure or big picture representation.

(6) Location and method of cable down point.

(7) The cable tray should be higher than 2.2m above the ground, the distance between the top of the tray and the ceiling or other obstacles should not be less than 0.3m, the width of the tray should not be less than 0.1m, and the filling rate of the cross section in the tray should not exceed 50%.

(8) When the cable is laid vertically in the cable bridge, the upper end of the cable and every 1.5m should be fixed on the bracket of the bridge.

(9) When installed in the ceiling, the opening surface of the slot cover should maintain a vertical clearance of 80mm, and the utilization rate of the wire channel section should not exceed 50%.

(10) The cables placed in the cable trough may not be tied. The cables in the trough should be straight and not crossed as much as possible. The cables should not overflow the cable trough. At the place where the cable enters and exits the cable trough, the corners should be tied and fixed.

(11) When laying cables in horizontal and vertical bridges and vertical cable troughs, the cables should be bundled.

(12) When the bridge is laid horizontally, the support spacing is generally 1.5 to 3m, and the distance fixed to the building structure when laid vertically should be less than 2m.

(13) When laying metal wire ducts, install up to racks or hangers under the following conditions:

● The joint of the trunking; ● The spacing is 3m; ● 0.5m away from the two ports of the trunking; ● The turning point.

In addition, the following points should be noted in material statistics.

(1) Bridge frame: The total length of various models and various specifications of the bridge frame required for the project are separately counted and divided by the standard length of the bridge frame to obtain the number of the required bridge frame and increase by 1% on this basis ~ 2% margin.

(2) Columns: If columns of uniform specifications are used, the total length of the bridge can be divided by the average column spacing to obtain the number of columns, and then increase the margin by 2% to 4%. If the column specifications are different, they need to be counted separately.

(3) Support arm: The total length of the bridge is divided by the average spacing of the support arms, and the remaining margin is increased by 1% to 2%, which is the total demand.

(4) Other components: The total number is obtained by multiplying the number of its main body by a certain proportion (depending on the total factory). Special parts such as vertical bending plates and turning plates need to be counted separately.

7.6 Laying technology of twisted pair cables

7.6.1 Wiring safety of twisted pair

In the twisted pair wiring project, the personnel participating in the construction should observe the following points:

● Wear appropriate clothes; ● Use safe tools; ● Ensure the safety of the work area; ● Formulate construction safety measures.

7.6.2 General requirements for the deployment of twisted pairs

(1) Before laying the cable, check whether its specifications, programs, routing and location are in accordance with the design requirements.

(2) The cables to be laid should be straight, without twisting or twisting, and should not be squeezed or damaged by external force.

(3) Before laying, labels should be attached to both ends of the cable to indicate the start and end positions and the label of the information point. The label writing should be clear, correct and correct.

(4)信号电缆、电源线、双绞线缆、光缆及建筑物内的其他弱电线缆应分离布放。

(5)布放的线缆应有冗余。

(6)布放线缆时，在牵引过程中吊挂线缆的支点相隔间距不应大于1.5m。

(7)线缆布放过程中为了避免受力和扭曲，应制作合格的牵引端头。

7.6.3 放线

1.从线缆箱中拉线

⑴.除去塑料塞；

⑵.通过出线孔拉出数米的线缆；

⑶.拉出所要求长度的线缆，割断它，将线缆滑回到槽中去，留数厘米伸出在外面；

⑷.重新插上塞子以固定线缆。

2.线缆处理(剥线)

⑴.使用斜口钳在塑料外衣上切开“1”字型长的缝；

⑵.找出尼龙的扯绳；

⑶.将电缆紧握在一只手中，用尖嘴钳夹紧尼龙扯绳的一端，并把它从线缆的一端拉开，拉的长度根据需要而定；

⑷.割去无用的电缆外衣。

7.6.4 线缆牵引技术

线缆牵引技术：用一条拉线将线缆牵引穿入墙壁管道、吊顶和地板管道的技术。它所用的方法取决于要完成工程的类型、线缆的质量、布线路由的难度。

1)牵引多条4对双绞线的方法一

⑴.将多条线缆聚集成一束，并使它们的末端对齐；

⑵.用电工胶带紧绕在线缆束外面，在末端外绕长5～6cm；

⑶.将拉绳穿过电工带缠好的线缆并打好结。

2)牵引多条4对双绞线的方法二

如果在拉线缆过程中连接点散开了，则要收回线缆和拉线重新制作，因此拉线和双绞线需要更牢靠的固定连接。

⑴.除去一些绝缘层，暴露出5cm的裸线；

⑵.将裸线分成两束；

⑶.将两束导线互相缠绕起来形成环；

⑷.将拉绳穿过此环并打结，然后将电工带缠到连接点周围，要缠得结实和平滑。

3)牵引单条25对双绞线的方法

⑴.将缆向后弯曲以便建立一个环，直径约150～300mm，并使得线缆末端与线缆本身绞紧；

⑵.用电工带紧紧地缠在绞好的线缆上，以加固此环；

⑶.把拉绳拉接到缆环上；

⑷.用电工带紧紧地将连接点包扎起来。

4)牵引多条25对双绞线的方法

⑴.剥除约30cm的线缆护套，包括导线上的绝缘层；

⑵.使用针口钳将线切去，留下约12根；

⑶.将导线分成两个绞线组；

⑷.将两组绞线交叉的穿过拉线的环，在线缆的那边建立一个闭环；

⑸.将双绞线一端的线缠绕在一起以使环封闭；

⑹.将电工带紧紧地缠绕在线缆周围，覆盖长度约5cm，然后继续再绕上一段。

7.6.5 建筑物水平干线布线

1.管道布线

管道布线是在浇筑混凝土时已把管道预埋在地板中，管道内有牵引电缆线的钢丝或铁丝。施工时只需通过管道图纸了解地板管道，就可做出施工方案。

对于没有预埋管道的新建筑物，布线施工可以与建筑物装潢同步进行，这样便于布线，又不影响建筑的美观。

管道一般从管理区埋到信息插座安装孔，施工时只要将双绞线固定在信息插座的接线端，从管道的另一端牵引拉线就可将线缆引到管理间。

2.吊顶内布线

⑴.索取施工图纸，确定布线路由。

⑵.沿着所设计的路由(即在电缆桥架槽体内)打开吊顶，用双手推开每块镶板。

⑶.将多个线缆箱并排放在一起，并使出线口向上。

⑷.加标注。纸箱上可直接写标注，线缆的标注写在线缆末端，贴上标签。

⑸.将合适长度的牵引线连接到一个带卷上。

⑹.从离配线间最远的一端开始，将线缆的末端(捆在一起)沿着电缆桥架牵引经过吊顶走廊的末端。

⑺.移动梯子，将拉线投向吊顶的下一孔，直到绳子到达走廊的末端。

⑻.将每两个箱子中的线缆拉出形成“对”，用胶带捆扎好。

⑼．将拉绳穿过3个用带子缠绕好的线缆对，绳子结成一个环，再用带子将3对线缆与绳子捆紧。

⑽．回到拉绳的另一端，人工牵引拉绳，所有的6条线缆(3对)将自动从线箱中拉出并经过电缆桥架牵引到配线间。

⑾．对下一组线缆(另外3对)重复步骤8的操作。

⑿．继续将剩下的线缆组增加到拉绳上，每次牵引它们向前，直到走廊末端，再继续牵引这些线缆一直到达配线间连接处。

7.6.6 建筑物垂直干线布线

在竖井中敷设垂直干线一般有两种方式：向下垂放电缆和向上牵引电缆。相比较而言，向下垂放比向上牵引容易。

1.向下垂放线缆的一般步骤

⑴.把线缆卷轴放到最顶层。

⑵.在离房子的开口(孔洞处)3～4m处安装线缆卷轴，并从卷轴顶部馈线。

⑶.在线缆卷轴处安排所需的布线施工人员(人数视卷轴尺寸及线缆质量而定)，另外，每层楼上要有一个工人，以便引寻下垂的线缆。

⑷.旋转卷轴，将线缆从卷轴上拉出。

⑸.将拉出的线缆引导进竖井中的孔洞。在此之前，先在孔洞中安放一个塑料的套状保护物，以防止孔洞不光滑的边缘擦破线缆的外皮。

⑹.慢慢地从卷轴上放缆并进入孔洞向下垂放，注意速度不要过快。

⑺.继续放线，直到下一层布线人员将线缆引到下一个孔洞。

⑻.按前面的步骤继续慢慢地放线，并将线缆引入各层的孔洞，直至线缆到达指定楼层进入横向通道。

2.向上牵引线缆的一般步骤

条件：需要使用电动牵引绞车

⑴.按照线缆的质量，选定绞车型号，并按绞车制造厂家的说明书进行操作。先往绞车中穿一条绳子。

⑵.启动绞车，并往下垂放一条拉绳(确认此拉绳的强度能保护牵引线缆)，直到安放线缆的底层。

⑶.如果缆上有一个拉眼，则将绳子连接到此拉眼上。

⑷.启动绞车，慢慢地将线缆通过各层的孔向上牵引。

⑸.缆的末端到达顶层时，停止绞车。

⑹.在地板孔边沿上用夹具将线缆固定。

⑺.当所有连接制作好之后，从绞车上释放线缆的末端。

7.6.7 建筑群间电缆布线技术

在建筑群中敷设线缆时，一般采用两种方法，即地下管道敷设和架空敷设。

1.管道内敷设线缆

在管道中敷设线缆时，有3种情况：

●小孔到小孔敷设；●在小孔间的直线敷设；●沿着拐弯处敷设。

可用人和机器来敷设线缆，到底采用哪种方法，依赖于下述因素：

●管道中有没有其他线缆；●管道中有多少拐弯；●线缆有多粗和多重。

由于很难确切地说是用人力还是用机器来牵引线缆，因此只能依照具体情况来解决。

2.架空敷设线缆

⑴.电杆以30～50m的间隔距离为宜；

⑵.根据线缆的质量选择钢丝绳，一般选8芯钢丝绳；

⑶.接好钢丝绳；

⑷.架设线缆；

⑸.每隔0.5m架一个挂钩。

7.6.8 6类布线安装方法

1.电缆的拉伸张力

在进行6类布线的时候，不要超过电缆制造商规定的电缆拉伸张力。张力过大会使电缆中的线对绞距变形，严重影响电缆抑制噪音(包括近端串扰、远端串扰及其衍生物)能力以及电缆的结构化回波损耗，进而改变电缆的阻抗，损害整体回波损耗性能，影响高速局域网(如千兆以太网)的传输性能。此外，张力过大还可能导致线对散开，损坏导线。

2.电缆的弯曲半径

一般情况下，电缆制造商都建议，安装后的电缆弯曲半径不得低于电缆直径的8倍。对典型的6类电缆而言，弯曲半径应大于50mm。

3.电缆的压缩

避免使电缆扎线带过紧而压缩电缆。在大的成捆电缆或电缆设施中最可能发生这个问题，其中成捆电缆中外面的电缆会比内部的电缆承受更多的压力。压力过大会使电缆内部的绞线变形，影响其性能，一般会使回波损耗处于不合格状态。

4.电缆的重量

在使用悬挂线支撑电缆时，必须考虑电缆的重量。电缆的重量因制造商而异，比如Molex企业布线网络部23号(直径为0.6mm)6类电缆的重量大约是5类电缆的两倍。

5.电缆的打结

在从卷轴上拉出电缆时，要注意电缆可能会打结。电缆打结就应视为损坏，应更换电缆。因为即使弄直电缆结，损坏也已经发生，这一点可以通过对电缆的测试得到验证。

6.成捆电缆中的电缆数量

当任意数量的电缆以很长的平行长度捆在一起时，其中具有相同绞距的不同电缆的线对电容耦合(如蓝线对到蓝线对)会导致串扰明显提高，这称为“外来串扰”。这一指标还有待布线标准的规范或精确定义。

7.电缆护套剥开的长度

在电缆端接点上进行端接后，从外皮到IDC(绝缘置换连接器)之间露出的线对必须保持最小长度。剥开的护套长度越小，越有利于电缆内部的线对保持绞距，实现最有效的传输通路。

8.线对的散开

在线缆端接点，应使电缆中的每个线对的绞距尽可能靠近IDC。线对绞距由电缆制造商计算后确定，改变它们将给电缆性能带来不利影响。

9．环境温度

环境温度在5类和超5类布线中已经是个问题，在6类布线中更为严重。因为环境温度会影响电缆的传输特点，所以，应尽量避免可能遇到的高温环境。

7.6.9 布线系统中线缆标识的选择

选择了适合的标签后，第二个应考虑的问题是如何印制标签，可选的方法包括以下几种：

(1)使用预先印制的标签。预先印制的标签有文字或符号两种。

(2)使用手写的标签。手写标签要借助于特制的标记笔，书写内容灵活、方便，但要特别注意字体的工整与清晰。

(3)借助软件设计和打印标签。对于需求数量较大的标签而言，最好的方法莫过于使用软件程序，这类软件程序在印制标准的标签或设计与印制用户自己的专用标签时可提供最大的灵活性。

(4)使用手持式标签打印机现场打印。

7.7 综合布线接地保护技术

7.7.1 综合布线系统接地的结构组成

根据商业建筑物接地和接线要求的规定，综合布线系统接地的结构包括接地线、接地母线(层接地端子)、接地干线、主接地母线(总接地端子)、接地引入线和接地体6部分。在进行系统接地的设计时，可按上述6个要素分层进行设计。

1.接地线

接地线是指综合布线系统各种设备与接地母线之间的连线，所有接地线均为铜质绝缘导线，其截面应不小于4mm2。表7.3即是接地导线与地面距离的参考选择说明。

2.接地母线(层接地端子)

接地母线是水平布线子系统接地线的公用中心连接点。

3.接地干线

接地干线是由总接地母线引出，连接所有接地母线的接地导线。

4.主接地母线(总接地端子)

一般情况下，每栋建筑物都有一个主接地母线。主接地母线作为综合布线接地系统中接地干线及设备接地线的转接点，其理想位置宜设于外线引入间或建筑管理间。

5.接地引入线

接地引入线指主接地母线与接地体之间的接地连接线，宜采用镀锌扁钢。接地引入线应作绝缘防腐处理，在其出土部位应有防机械损伤措施，且不宜与暖气管道同沟布放。

6.接地体

接地体分自然接地体和人工接地体两种。当综合布线采用单独接地系统时，接地体一般采用人工接地体，并应满足以下条件：

(1)距离工频低压交流供电系统的接地体不宜小于10m。

(2)距离建筑物防雷系统的接地体不应小于2m。

(3)接地电阻不应大于4Ω。当综合布线采用联合接地系统时，接地体一般利用建筑物基础内钢筋网作为自然接地体，其接地电阻应小于1Ω。

●当建筑物遭受雷击时，楼层内各点电位分布比较均匀，工作人员及设备的安全能得到较好的保障。同时，大楼的框架结构对中波电磁场能提供10～40dB的屏蔽效果。

●容易获得较小的接地电阻。

●可以节约金属材料，占地少。

7.7.2 接地设计应注意的几个问题

1.屏蔽保护接地

在屏蔽保护接地系统设计中应注意以下几点：

(1)具有屏蔽性能的建筑群子系统的主干电缆(包括公用通信网等各种引入电缆)在进入房屋建筑后，应在电缆屏蔽层上(即接地点)焊好直径为5mm的多股铜芯线，并连接到临近入口处的接地线装置上，要求焊接牢靠稳固。接地线装置的位置距离电缆入口处不应大于15m(入口处是指电缆从管道的引出处)，同时应尽量使电缆屏蔽层接地点接近入口处。

(2)综合布线系统所有缆线均采用了具有屏蔽性能的结构，且在利用其屏蔽层组成整体系统性接地网时，在设计中要明确规定，施工中对各段缆线的屏蔽层都必须保持360°良好的连续性相互连接，并应注意导线相对位置不变。

(3)综合布线系统为屏蔽系统时，其配线设备端也应接地，用户终端设备处的接地视具体情况来定。两端的接地应尽量连接在同一接地体(即单点接地)。

(4)由于采用屏蔽系统的工程建设投资较高，有时为了节约投资，不得不采用非屏蔽缆线，或者虽然使用了屏蔽缆线，但是屏蔽层的连续性和接地系统却得不到保证。在上述两种情况下应采取以下措施：

●在非屏蔽缆线的路由附近敷设直径为4mm的铜线作为接地干线，其作用与电缆屏蔽层完全相同，并要求像电缆屏蔽层一样采取接地措施。

●在需要屏蔽缆线的场合，如采用非屏蔽缆线穿放在钢管或金属槽道(或桥架)内敷设时，要求各段钢管或金属槽道应保持连续的电气连接，并在其两端有良好的接地。

(5)综合布线系统中的干线交接间应有电气保护和接地。其要求是：

●干线交接间中的主干电缆如为屏蔽结构，且有线对分支到楼层时，除应按要求将电缆屏蔽层连接外，还应做好接地。

●干线交接间中主干电缆的位置应尽量靠近垂直的接地导体(如高层建筑中的钢结构)，并尽可能位于建筑物内部的中心部位。

2.安全保护接地和防雷保护接地

(1)当通信线路处在下述的任何一种情况时，就认为该线路处于危险环境内，根据规定应对其采取过压、过流保护措施。

●雷击引起的危险影响；●工作电压超过250V的电源线路碰地；●地电位上升到250V以上引起的电源故障；●交流50Hz感应电压超过250V。

(2)当通信线路能满足和具有下述任何一个条件时，可认为通信线路基本不会遭受雷击，其危险性可以忽略不计。

●该地区每年发生的雷暴日不大于5天，其土壤电阻率ρ小于或等于100Ω·m。

●建筑物之间的通信线路采用直埋电缆，其长度小于42m。

●通信电缆全程完全处于已有良好接地的高层建筑中，或其他高耸构筑物所提供的类似保护伞的范围内(有些智能化小区具有这样的特点)，且电缆有良好的接地系统。

(3)综合布线系统中采取过压保护措施的元器件，目前有气体放电管保护器或固态保护器两种，宜选用气体放电管保护器。固态保护器因价格较高，所以不常采用。

(4)综合布线系统的缆线会遇到各种电压，过压保护器并不能完全保护系统。

(5)当智能化建筑避雷接地采用外引式泄流引下线入地时，通信系统接地应与建筑避雷接地分开设置，并保持规定的间距。

●当建筑物遭受雷击时，楼内各点电位的分布比较均匀，工作人员和所有设备的安全将得到较好的保障。

●较容易采取比较小的接地电阻值。

●节省金属材料，占地少，不会发生矛盾。

(6)当采用联合接地方式时，为了减少危险，要求总接线排的工频接地电阻不应大于1Ω，以限制接地装置上的高电位值出现。

(7)智能化建筑内综合布线系统的有源设备的正极和外壳、主干电缆的屏蔽层及其连通线均应接地，并应采用联合接地方式。

(8)信息插座的接地可利用电缆屏蔽层连至每层的配线柜上。

(9)综合布线的电缆采用金属槽道或钢管敷设时，槽道或钢管应保持连续的电气连接，并在两端应有良好的接地。

(10)干线电缆的位置应接近垂直的地导体(例如建筑物的钢结构)，并尽可能位于建筑物的网络中心部位。

7.8 综合布线系统的防护技术

7.8.1 防护的必要性和重要性

目的：主要是防止外来的电磁干扰和向外产生电磁辐射，前者直接影响综合布线系统的正常运行，后者则是综合布线系统传递信息时产生泄露的原因。

(1)通信网络的传输速率迅速提高，导致容易产生向外的电磁辐射和受到外界的电磁干扰。

(2)电磁干扰源日益

A Aluminum Stranded Conductor(AAC)is a bare conductor (non-insulated conductor) applicable for electrical power transmission in modern overhead power line with various voltage levels. It has cost and weight advantages while comparing to copper wires and cables. And it is as simple as installing copper wires. We have common aluminum conductor, rare earth aluminum stranded conductor with both single layer or multi layer construction.

Main advantages

Attractive price with high standard quality

Higher strength, good electrical conductivity

Simple structure, convenient installation and maintenance

 

Product features

Range:16 to 800 sq mm²

Voltage Rating: Up to 500kV

Delivery length:800-4000m

Standard: IEC61089

 

 

 

 

Application

This cable is widely used in overhead electrical power transmission lines with rated voltage up to 500kV. It is also applicable for laying across the rivers, valleys and other places where special geographical features exist.

 

FAQ

 

Q: Are you a factory or trading company? 
A : We are a manufacturer. We are professional in developing and producing electrical wires and cables since 2001.

 

Q: Can I visit your factory? 

A :Yes!  You are welcome to visit our factory for further detail check.

Our factory is located in Minqing,Fujian.You could choose to fly to Xiamen/Fuzhou International airport. And tell us your flight No. We will arrange to pick you up if you like.

 

Q: May I buy samples from you? 

A: Yes! You are welcome to place sample order to test our superior quality and services.

 

 

Q: Can you put my brand name (logo) on these products?

A: Yes! Our factory accepts to print your logo on the products.

 

Q: May I know the status of my order?

A: Yes .The order information and photos at different production stage of your order will be sent to you and the information will be updated in time.

 

 

As a professional manufacturer, we also welcome OEM order according to relevant standard as your request. Please feel free to contact us if you are inquiry electrical wires and cables.

Aluminum Stranded Conductor

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