Integrated wiring system engineering design
Structured Cabling (Structured Cabling System): Combines several kinds of wiring systems in the building group, including telephone system, data communication system, alarm system and monitoring system into a kind of wiring system
Physical Security: Measures and processes to protect computer equipment, facilities (including networks) and other media from earthquakes, floods, fires, harmful gases, and other environmental accidents (such as electromagnetic pollution, etc.).
Comprehensive wiring components
Building group distribution frame (CD); building group trunk cable, building group trunk cable; building distribution frame (BD); building trunk cable, building trunk optical cable; floor distribution frame (FD); horizontal cable, horizontal Optical cable; transfer point (optional) (TP); information socket (IO); communication outlet (TO).
General principles of integrated wiring system design
⑴ Compatibility; ⑵ Openness; ⑶ Flexibility; ⑷ Reliability; ⑸ Advanced; ⑹ Scalable; ⑺ Economic; ⑻ Standardization and standardization
Design Points
â‘´ As far as possible to meet the user's communication requirements;
⑵ Understand the communication environment between buildings and buildings;
⑶ determine the appropriate communication network topology;
â‘· Select the applicable medium;
⑸ Based on the open style, try to be compatible with most manufacturers' products and equipment;
⑹ Inform users of preliminary system design and construction cost budget
Different principles of objects in system design
1) For professional buildings with clear functions, the layout of information sockets can be determined according to actual needs.
2) For ordinary office buildings of government agencies, enterprises and institutions, the configuration of information sockets can be designed according to the principles stipulated in the design level in accordance with the actual situation of the unit.
3) For commercial buildings such as office buildings and comprehensive buildings developed by the real estate department, an open office environment integrated wiring structure should be adopted.
4) When multi-user information sockets are used, the multi-user sockets should be installed on fixed structures such as walls or pillars. Each multi-user socket includes a maximum of 12 information sockets, including the appropriate backup amount.
General steps for integrated wiring design
(1) Analyze user needs; (2) Obtain building plan; (3) System structure design; (4) Wiring routing design; (5) Feasibility demonstration; (7) Draw comprehensive wiring construction drawing; (5) Prepare comprehensive wiring bill of materials.
A perfect and reasonable integrated wiring goal:
Within a given time, when new requirements are allowed during the integration process, it is no longer necessary to perform horizontal wiring, so as not to damage the building structure or decoration and affect the appearance.
Reasons for not to perform horizontal wiring:
Horizontal wiring is in the ceiling of the building, the ground wire channel or the pipeline, and the construction cost is higher than the material cost of the initial investment. If the horizontal wiring is replaced, the building structure will be damaged and the overall appearance will be affected.
The design principle of the overall planning of the integrated wiring: The overall planning is implemented step by step, and the horizontal wiring is as far as possible.
The principles for determining the number and type of information sockets are:
1. According to the customer's needs, determine the type of information socket;
2. Calculate the actual available space according to the building plan, and determine the number of information outlets according to the size of the space.
RJ45 head demand is generally calculated in the following way:
m = n × 4 + n × 4 × 15%
m: indicates the total demand of RJ45. n: indicates the total amount of information points. n × 4 × 15%: indicates the remaining margin.
The demand for information modules is generally:
m = n + n × 3%
m: indicates the total demand of the information module. n: indicates the total amount of information points. n × 3%: indicates surplus.
Work area design points
â‘´ The laying of wire grooves in the work area should be reasonable and beautiful;
⑵ The information socket is designed above 30cm from the ground;
⑶ Keep the distance between the information socket and the computer equipment within 5m;
â‘· The network card interface type should be consistent with the cable interface type;
⑸ The number of information modules, information sockets and panels required in all work areas must be accurate;
⑹ The number of RJ45 crystal heads required.
When designing the work area, specific operations can be performed in the following three steps:
⑴ Calculate the wiring area of ​​each floor according to the floor plan.
⑵ To estimate the number of information outlets, generally design two kinds of floor plans for users to choose: design a floor plan of one information outlet per 9 square meters for the basic model; design two floor plans of the information outlet for the enhanced or integrated model.
(3) Determine the type of outlet that the information leads to.
Wiring subsystem: It is composed of the information socket in the work area, the wiring or optical cable from the information socket to the floor wiring equipment (FD), floor wiring equipment and jumpers.
The difference between the wiring subsystem and the trunk subsystem: the wiring subsystem is always on the same floor and is terminated at the relay point of the information socket or area wiring.
The design of the horizontal trunk subsystem involves the integration of the transmission medium and components of the horizontal subsystem. There are 6 main points:
1) Determine the direction of the line; 2) Determine the number and type of cables, slots and pipes;
3) Determine the type and length of the cable; 4) Order cables and trunking;
5) How many hangers are needed if the hanger cable trough is used; 6) How many brackets are needed if the hanger cable trough is not used.
Determining the direction of the line is generally established by users, designers, and construction personnel to the site according to the physical location of the building and the ease of construction.
Horizontal subsystem design requirements
â‘´According to the user's short-term and long-term terminal equipment requirements for the project.
⑵The number and location of information sockets to be installed on each floor.
(3) Details of terminal equipment that may be added, moved and rearranged in the future.
â‘·Comparison of one-off construction and phased construction.
General principles of cable selection:
â‘´ Product selection must be combined with the actual project.
⑵ The selected products should conform to China's national conditions and relevant technical standards (including international standards, China's national standards and industry standards).
⑶ Combination of short-term and long-term
â‘· In line with the principle of unification of advanced technology and economic rationality.
There are three calculation formulas for cables. The three methods are:
1) Total order quantity (total length m) = required total length + required total length × 10% + n × 6
Among them: the total length required: refers to the theoretical length required for n wiring cables; the total length required × 10% is the spare part; n × 6 is the termination tolerance.
2) Wire consumption of the whole building = Σ NC
N: the number of floors; C: the amount of wire used per floor;
C = [0.55 × (L + S) +6] × n;
L: the distance of the information point farthest from the level between this floor; S: the distance of the information point closest to the level between this floor;
n: total number of information sockets on this floor; 0.55: standby factor; 6: termination tolerance.
3) Total length = A + B / 2 × N × 3.3 × 1.2
A: The shortest information point length; B: The longest information point length; N: The number of information points to be installed in the building;
3.3: Factor 3.3, replace meters (m) with feet (ft); 1.2: margin parameter (surplus).
Number of wire boxes = total length / 1000 + 1
Twisted pairs are generally ordered in units of boxes, and the length of each twisted pair is 305m.
Designers can use one of these 3> algorithms to determine the required cable length.
When suspending the cable trough, it is generally a pair of suspenders with a spacing of about 1m. The total amount of booms should be the length of the horizontal trunk (m) × 2 (root).
When using the bracket cable trough, a bracket is generally installed from 1 to 1.5m. The requirement of the bracket should be calculated according to the actual length of the horizontal trunk line.
The bracket should be selected according to the actual situation of the trunking. There are generally 2 situations:
1) If the horizontal wire slot does not stick to the wall, you need to order the bracket; 2) When the horizontal wire sticks to the wall, you can buy a self-made bracket of angle steel.
Patch panel
Function: Make the data cables of all information points be concentrated on the distribution frame.
Common distribution frames include RJ45 distribution frames, telephone distribution frames, and fiber distribution boxes.
Horizontal subsystem wiring distance
1. The maximum length of horizontal cable and horizontal optical cable is 90 meters.
2. The total length of patch cords in the work area, equipment patch cords and floor patch panels is generally ≤10 meters.
3. Horizontal wiring model of twisted pair cable.
4. When the performance of the link can be guaranteed, the distance of the horizontal optical cable is allowed to be properly lengthened, exceeding 90 meters.
5. In some larger rooms, a transfer point can be set between the floor distribution frame and the information socket (up to one transfer).
Horizontal subsystem wiring scheme
The designer should consider the shortest route (line), the lowest cost, convenient construction, and wiring specifications according to the structural characteristics of the building.
Horizontal subsystem wiring can generally use the following three types:
1) Direct buried tube type;
2) First, take the inner cable trough of the suspended ceiling, and then take the way of the branch pipe to the information outlet;
3) It is suitable for ground ducts in large bays and rear partitions.
The rest are improved and integrated types of these three methods.
Advantages of ground wire way:
1) Using the surface wire way, the distance between the information outlet and the weak current well is not limited. The ground wire channel is connected to a distribution box or outlet box every 4 ~ 8m. It is very easy to pull the wire when wiring, so the distance is not limited.
2) The strong and weak currents can be routed in the same way. The strong and weak currents can be routed to the adjacent ground wire ducts, and can be connected to their respective sockets in the same wire box. Of course, the ground wire channel must be grounded and shielded, and the quality of the product must pass.
Disadvantages of the ground wire way:
1) When the ground wire groove is used in the ground cushion, a cushion thickness of at least 6.5 cm or more is required, which is unfavorable for reducing the thickness of the baffle and cushion as much as possible.
2) Since the ground duct is made in the ground cushion, if the floor is thin, it may be hit by the boom during the decoration of the ceiling and affect its use.
3) Not suitable for occasions where there are many information points on the floor.
Therefore, it is recommended that more than 300 information points should be used at the same time with the ground wire groove and the ceiling inner wire groove to reduce the pressure of the ground wire groove.
4) Not suitable for stone ground.
5) The cost is expensive.
At present, most of the ground wire ducts are used in high-end conference rooms and other buildings.
The following points should be noted in the selection and design:
1) When selecting the model, those manufacturers with strong strength should be selected, and their products must pass the national electrical shielding test to avoid the impact of strong and weak currents on the data; when laying the ground wire channel, the manufacturer should send technical personnel to guide on site The problems will be discovered after the cushion and affect the construction period.
2) The design should be based on the layout of the office furniture provided by the owner, to avoid the ground wire channel exit being blocked by office furniture. When there is no office furniture plan, the ground wire channel should be evenly distributed on the ground outlet; for rooms with anti-static floors , Only need to lay a distribution box, go out and lay under the static floor.
3) The trunk part of the ground wire channel should be placed in the cushion of the corridor as much as possible. There are many information points on the floor, and the two methods of combining the ground pipe and the inner trough in the ceiling should be used at the same time.
Trunk subsystem
The concept of the trunk subsystem: It is composed of the building wiring equipment between the equipment, jumpers, and the trunk cable between the equipment and the crossover between each floor. It must meet current needs and adapt to future development.
The trunk subsystem includes:
1) Vertical or horizontal channels for cable routing between trunk lines
2) The cable between the main equipment and the computer center.
Consider the following points when designing:
1) Determine the trunk requirements for each floor; 2) Determine the trunk requirements for the entire building;
3) Determine the trunk cable route from the floor to the equipment; 4) Determine the joining method between the trunk wiring;
5) Select the length of the trunk cable; 6) Determine the supporting structure when laying additional horizontal cables.
General principles of trunk subsystem design:
â‘´ Before determining the total number of cables required by the trunk subsystem, the principle of sharing voice and data signals in the cable must be determined.
⑵ The shortest, safest and most economical route for the trunk cable should be selected.
(3) The trunk cable can be terminated point-to-point, or branch-decreasing termination and direct cable connection.
â‘· If the equipment room and the computer room are in different locations, and you need to connect the voice cable to the equipment room and the data cable to the computer room, you should choose different parts of the trunk cable in the design to meet the needs of voice and data.
The structure of the vertical trunk subsystem is a star structure; the vertical trunk subsystem is responsible for connecting the trunks of each management room to the equipment room.
Design method of vertical trunk subsystem:
To determine the route from the management room to the equipment, the shortest, safest and most economical route should be selected. There are usually two methods in the building: 1) cable hole method; 2) cable well method
Twisted pair cable in the trunk
1) The wire should be straight, and the cable trough should not be twisted; 2) Both ends should be marked;
3) It is necessary to add a casing outside the room, and it is strictly prohibited to overlap on the trunk; 4) Do not bend the twisted pair hard.
Coaxial thin cable
The laying of coaxial thin cable is different from the coaxial thick cable in the following points:
1) The bending radius of the thin cable should not be less than 20cm;
2) The distance between each station on the thin cable is not less than 0.5m;
3) Generally, the length of the thin cable is 183m, and the thickness of the thick cable is 500m.
Steps for wiring design of trunk subsystem
1. Determine the trunk cable requirements for each floor Select the trunk cable category based on different needs and economic factors.
2. Determine the trunk cable routing principles, which should be the shortest, safest, and most economical.
3. Draw the trunk line from the drawing using the graphics and symbols specified in the standard to draw the cable routing diagram of the vertical subsystem. The drawing should be clear and tidy.
4. Determining the size of the trunk cable The length of the trunk cable can be actually measured on the drawing using the scale, or it can be calculated using the arithmetic sequence. The length of each trunk cable should have a spare part (about 10%) and termination tolerance.
Fiber optic cable laying
1) It should not be twisted when laying;
2) When wiring indoors, the cable trough should be used;
3) Use PVC pipes when passing through underground pipes;
4) When turning is required, the radius of curvature should not be less than 30cm;
5) The exposed parts of the outdoor should be protected with iron pipes, and the iron pipes should be firmly fixed;
6) Do not pull too tight or too loose, and have a certain expansion and contraction margin;
7) When buried, iron pipes should be added for protection.
1. The concept of equipment room
The equipment room subsystem consists of cables, connectors and related supporting hardware in the equipment room, and interconnects various public system equipment through cables. It is a place where public equipment is stored, as well as a place where equipment is routinely managed. The equipment room can be shared with the computer room or can be set separately.
Second, the design principles of equipment
1. Points for attention when designing the equipment room:
1) The equipment room should be located in the middle of the trunk line complex;
2) It should be possible to be close to the cable entry area and network interface of the building;
3) The equipment room should be near the service elevator to facilitate the shipment of bulky equipment;
4) Pay attention to in the equipment room:
? No dust in the room, good ventilation, and better lighting brightness;
? Install a fire protection system that meets the specifications of the equipment room;
? Use fire doors and flame retardant paint on the walls;
? Provide a suitable door lock, at least one safe passage.
5) Prevent disasters caused by possible water hazards (such as rainstorms, water pipe bursts, etc.);
6) Try to stay away from harmful gas sources, corrosion, flammable, explosives and electromagnetic field interference;
7) The space between the equipment (from the ground to the ceiling) should maintain a height of (2.5-3.2m) without obstacles, the door height ≥2.1m, width ≥90m, and the floor load-bearing pressure should not be less than 500kg / m2.
2. When designing the equipment room, the following elements must be grasped:
1) Minimum height; 2) Room size;
3) Lighting facilities; 4) Floor load;
5) Electrical socket; 6) Power distribution center;
7) Location of pipeline; 8) Temperature control in the building;
9) The size, direction and position of the door;
10) Termination space; 11) Grounding requirements;
12) Backup power supply; 13) Protection facilities;
14) Fire fighting facilities.
3. Conclusion: The following principles should be grasped in the equipment room design:
1. Principle of recentness and convenience 2. Principle of selection of area and net height of main transfer room 3. Principle of grounding
4. Color code principle 5. Operation convenience principle
Third, the design steps between the equipment
The implementation of the design can be divided into two steps.
1. Select and determine the hardware scale of the main wiring field Selection and determination of relay field / auxiliary field
4. Main equipment in the equipment room
The hardware of the subsystem between the equipment is roughly the same as the hardware of the management subsystem, which is basically composed of optical fiber, copper cable, jumper frame, lead frame, and jumper, but it is much larger than the management subsystem.
5. The use area of ​​the equipment room
The main equipment between the equipment is digital program-controlled switches, computers, etc., for its use area, there must be a comprehensive consideration. At present, there are two methods to determine the area of ​​use between equipment.
Method 1: Area S = K∑Si i = 1,2, ..., n
S: total area used in the equipment room, m2;
K: coefficient, the area occupied by each device, generally K chooses 5, 6, 7 (select according to the size of the device)
∑: summation; Si: represents equipment parts; i: variable n: represents the total number of equipment in the equipment room.
Method 2: Area S = KA
S: total area used in the equipment room, m2; K: coefficient, (4.5-5.5) m2 / set (rack); A: total number of all equipment in the equipment room.
6. The environmental conditions for the design of subsystems in the equipment room
1. Temperature and Humidity
The temperature and humidity of the network equipment are generally divided into A, B, and C3 levels, and the equipment room can be executed according to a certain level, or can be executed according to a certain level.
2. Dust
The equipment has a requirement for the amount of dust in the equipment room. Generally can be divided into A, B2 level.
Conclusion: When designing the equipment room, in addition to the implementation of GB / T2887-2000 "General Specification for Electronic Computer Sites", the appropriate air conditioning system should be selected according to the specific situation.
Basis for selection of air conditioning equipment:
Several aspects of heat generation:
1) The device generates heat;
2) The peripheral structure of the equipment generates heat;
3) Heat generated by indoor staff;
4) Heat generated by lighting fixtures;
5) Replenish the heat brought by fresh air outdoors.
Calculate the total calorific value listed above and multiply it by a factor of 1.1 to use it as the air-conditioning load, and select the air-conditioning equipment accordingly.
3. Lighting
The illuminance should not be less than 200lx within 0.8m from the ground in the equipment room.
Accident lighting should also be set, and the illuminance should not be less than 5lx at a distance of 0.8m from the ground.
4. Noise
The noise between the equipment should be less than 65dB.
If you work in an environment with 65-80dB noise for a long time, it will not only affect people's physical and mental health and work efficiency, but also cause man-made noise accidents.
5. Electromagnetic interference
The radio interference field strength within the equipment is not greater than 120dB in the frequency range of 0.15 ～ 1000MHz.
The magnetic field interference field strength within the equipment is not greater than 800A / m (equivalent to 10Oe).
6. Power supply
The power supply between the equipment should meet the following requirements:
Frequency: 50Hz; Voltage: 380V / 220V; Phase number: three-phase five-wire system or three-phase four-wire system / single-phase three-wire system.
Power supply capacity between equipment:
After adding the nominal value of the power consumption of each device stored in the device room, it is multiplied by the coefficient (root number 3). The cables used from the power supply room (room) to the equipment room shall be reduced by 50% in addition to the wiring engineering provisions in GB50303-2002 "Code for Quality Acceptance of Building Electrical Engineering". The power distribution cabinet for equipment in the equipment room should be installed in the equipment room, and measures against electric shock should be taken.
The various power cables in the equipment room should be flame-resistant copper core shielded cables. For each Power Cable (such as the cable used for air conditioning equipment and power supply equipment), the power supply cable must not run parallel to the twisted pair. When crossing, try to cross at an angle close to vertical and take measures to prevent flame spread. All equipment should use copper core cables, and it is strictly prohibited to mix copper and aluminum.
7. Security
According to the requirements of GB9361-1988 "Computer Site Safety Requirements", the safety between equipments can be divided into three basic categories: Class A, Class B, and Class C: Class A: There are strict requirements for the safety of equipment, and there are perfect Safety measures; Class B: There are stricter requirements on the safety of equipment, and there are more complete safety measures between equipment; Class C: There are basic requirements on the equipment, and there are basic safety measures between the equipment.
8. Building fire protection and interior decoration
Class A, the fire resistance rating of its buildings must meet the first-grade fire resistance rating specified in GB50045-2001 "Code for Fire Protection Design of High-Rise Civil Buildings".
Class B, the fire resistance rating of its buildings must meet the secondary fire resistance rating specified in GB50045-2001 "Code for Fire Protection Design of High-Rise Civil Buildings".
For the remaining working rooms and auxiliary rooms related to Class A and B safety equipment rooms, the fire resistance rating of the building should not be lower than the second-level fire resistance rating specified in 2001.
For Class C, the fire resistance rating of the building shall comply with the secondary fire resistance rating specified in GBJ16-2001 "Code for Fire Protection of Building Design".
For the remaining basic working rooms and auxiliary rooms related to the Class C equipment room, the fire resistance rating of the building should not be lower than the three-level fire resistance rating specified in GBJ16.
Interior decoration: According to the requirements of Class A, B, C3, when decorating the equipment room, the decoration materials should comply with the incombustible materials or non-combustible materials specified in the "Code for Fire Protection of Architectural Design" of GBJ16-1987 (2001 edition), and should be able to resist moisture , Sound-absorbing, dust-free, anti-static, etc.
9. Ground
In order to facilitate the laying of cable and power lines on the surface, it is best to use anti-static raised floors for the ground between the equipment, and the system resistance should be between 1 * 105 ～ 1 * 1010Ω. The specific requirements should meet the standards of SJ / T10796-2001 "General Specification for Anti-static Raised Floors".
The raised floor with cable entry is called a special-shaped floor. The wiring should be smooth to prevent damage to wires and cables. The number of special-shaped floors required for the floor of the equipment room can be determined according to the number of leads required for the equipment room.
Do not lay carpet on the floor of the equipment room. The reason: first, it is easy to generate static electricity; second, it is easy to deposit dust.
The building floor of the equipment room where the raised floor is placed should be flat, smooth, moisture-proof, and dust-proof.
10. Wall
The wall should be made of materials that are not prone to dust or attract dust. At present, most of them are coated with flame retardant paint on smooth walls, or covered with fire-resistant plywood on smooth walls.
11. Ceiling
In order to absorb noise and arrange lighting fixtures, the equipment ceiling generally has a suspended ceiling under the building beam. The ceiling material should meet the fire protection requirements. At present, most of China adopts aluminum alloy or light steel as the keel, and installs sound-absorbing microporous aluminum alloy plates, flame-retardant aluminum-plastic plates, and plastic-sprayed quartz plates.
12. Partition
According to the equipment and work requirements placed in the equipment room, high-strength metal square tubes are used as brackets, and the equipment is divided into several rooms with glass. The partition can be made of fireproof aluminum alloy or light steel as the keel, and 10mm thick glass is installed. Or install the flame retardant double plastic board from the floor surface to 1.2m, and install 10mm thick glass above 1.2m.
13. Fire alarm and extinguishing facilities
According to the relevant provisions of GB50116-1998 "Code for Design of Automatic Fire Alarm System".
Fire alarm devices should be installed between Class A and B equipment. Smoke detectors and temperature detectors should be installed in the machine room, the basic work room, under the raised floor, above the ceiling, in the main air-conditioning ducts, and near flammable materials.
Class A equipment room is equipped with automatic carbon dioxide fire extinguishing system and equipped with portable carbon dioxide fire extinguisher.
When conditions permit, Class B equipment rooms should be equipped with automatic carbon dioxide fire extinguishing systems and portable carbon dioxide fire extinguishers.
A portable carbon dioxide fire extinguisher shall be provided in the category C equipment room.
Except for flammable substances such as paper media, it is forbidden to use fire extinguishing agents such as water, dry powder or foam that easily cause secondary damage.
4.7 Management Subsystem
Several forms of management subsystem interconnection: In different types of buildings, the management subsystem often adopts three methods: single point management single crosslink, single point management double crosslink and double point management double crosslink.
Fourth, the design principles of the management subsystem
1. Trunk wiring management should adopt double-point management and double handover.
2. Single point management should be adopted for floor wiring management.
3. The structure of the patch panel depends on the number of information points, the nature of the network of the integrated wiring system and the hardware selected.
4. The modularity of the terminating line is reasonable.
5. The device jumper connection method shall meet the following requirements:
For the relatively stable lines on the distribution frame that are generally not frequently modified, displaced or reorganized, the snap-in wiring method should be used; for the lines on the distribution frame that often need to be adjusted or reassembled, the quick-connect plug-in wiring method should be used ;
6. The list of wall materials for the column management wiring room should be comprehensive, and a detailed wall structure drawing should be drawn.
5. Design steps of the management room subsystem
1) Confirm whether the line modularity factor is 2 pairs or 3 pairs. Each line module is treated as a line, and the line modularity depends on the specific system. For example, System 85's line modularity factor is 3 pairs of lines.
2) Determine the total number of cable pairs to be terminated for voice and data lines, and allocate the wall or terminal strips required for voice or data lines.
3) Decide which 110 cross-connect hardware to use:
? If the total number of wire pairs exceeds 6000 (that is, 2000 lines), use 110A cross-connect hardware;
? If the total number of wire pairs is less than 6000, you can use 110A or 110P cross-link hardware;
The 110A cross-connect hardware point uses less wall space or frame space, but requires a technician to manage the line;
Determine the total number of pairs available for each terminal block. The number of white field wiring of the main wiring cross-connect hardware depends on 3 factors: the type of hardware, the total number of pairs available for each terminal block and the lines that need to be terminated The total number.
? Since the 25th pair of wires in each terminal block is usually not used, a terminal block can rarely accommodate all the pairs;
? Determine the number of wiring blocks in the white field. To do this, first divide the total number of input wire pairs required for each application (voice or data) by the total number of available wire pairs for each terminal block, and then take a higher integer as the number of white field terminal blocks;
? Select and determine the size of the cross-connect hardware-trunk / auxiliary field;
? Determine the location of cross-connect hardware between devices;
Draw a detailed construction drawing of the entire wiring system, that is, all subsystems.
4) The connection of the information point between the management is very important work, its connection should be as simple as possible, the main work is the jumper.
4.8 Building group subsystem
The transmission media connecting various buildings and various supporting equipment (hardware) form a comprehensive wiring system of a building group. The cables and corresponding equipment connecting the buildings constitute the building cluster subsystem.
2. AT & T recommended subsystem design
When wiring the building subsystems, the design steps recommended by AT & TPDS are:
1) Determine the characteristics of the laying site; 2) Determine the general parameters of the cable system; 3) Determine the cable entrance of the building; 4) Determine the location of obvious obstacles; 5) Determine the main cable route and backup cable route; 6) Select the location Cable type and specifications are required; 7) Determine the labor cost required for each option; 8) Determine the material cost of each option; 9) Select the most economical and practical design.
1. Determine the characteristics of the laying site
1) Determine the size of the entire construction site; 2) Determine the boundary of the construction site; 3) Determine how many buildings there are.
2. Determine the general parameters of the cable system
1) Confirm the location of the starting point; 2) Confirm the location of the termination points; 3) Confirm the buildings involved and the number of floors of each building;
4) Determine the number of twisted pairs required for each termination point; 5) Determine the total number of twisted pairs required for each building with multiple termination points.
3. Determine the cable entrance of the building
1) For existing buildings:
To determine the location of each inlet pipe; how many inlet pipes are available for each building; whether the number of inlet pipes meets the needs of the system.
2) If the inlet pipe is not enough:
To determine whether certain inlet pipes can be vacated when some cables are removed or rearranged; how many inlet pipes should be installed if not enough;
3) If the building has not been built, then
The cable system design should be perfected according to the selected cable routing, and the location of the entrance pipe should be marked; the specifications, length and materials of the entrance management should be selected; the entrance pipe should be installed during the construction of the building.
4. Determine the location of obvious obstacles
1) Determine the soil type: sandy soil, clay, gravel, etc .;
2) Determine the cable wiring method;
3) Determine the location of underground utilities;
4) Find out the location or geographical conditions of various obstacles along the planned cable route:
? Paving area;? Bridge;? Railway;? Forest;? Pond;? River;? Hill;? Gravel soil;?
5) Determine the requirements for the pipeline.
5. Determine the main cable route and the backup cable route
1) For each pending route, determine the possible cable structure;
2) All buildings share one cable;
3) Group all buildings and assign a cable to each group separately;
4) One cable for each building;
5) Find out where in the cable routing need to be approved before passing;
6) Compare the advantages and disadvantages of each route to select the best route plan.
6. Select the required cable type and specifications
1) Determine the cable length;
2) Draw the final structure diagram;
3) Draw a detailed drawing of the location and trenching of the selected route, including a public road map or any area sketches that require approval before they can be used;
4) Determine the specifications of the inlet pipeline;
5) Select the special cable required for each design scheme;
6) Refer to the relevant requirements of the AT & T SYSTIMAX PDS Component Guide for the cable number, twisted pair number and length in the cable section;
7) It should be ensured that the cable can enter the pipeline;
8) If you need to use pipes, you should choose their specifications and materials;
9) If you need to use steel pipes, you should choose their specifications, length and type.
7. Determine the labor cost required for each option
1) Determine the wiring time:
? Including the time taken to relocate or change roads, lawns, trees, etc.? If the pipeline area is used, it should include the time for laying pipes and cable;
2) Determine the cable connection time;
3) Determine other times, such as the time required to remove old cables and avoid obstacles;
4) Calculate the total time (1) item + 2) item + 3) item);
5) Calculate the cost of each design scheme;
6) The total time is multiplied by the local working hours fee;
8. Determine the material cost required for each option
1) Determine the cable cost:
• Determine the cost per foot (meter); • Refer to the relevant wiring material price list; • Determine the cost per 100 feet for each cable; • Divide the above cost by 100; • Multiply the cost per meter (foot) by Number of meters (feet);
2) Determine the cost of all support structures
• Identify and list all support structures; • Determine the unit price of each item according to the price list; • Multiply the unit price by the required quantity.
3) Determine the cost of all supporting hardware
For all supporting hardware, repeat the three steps listed in item (2).
9. Choose the most economical and practical design
1) Add the labor cost of each option to get the total cost of each option;
2) Compare the total cost of various schemes and choose the one with lower cost;
3) Determine whether the more economical plan has major shortcomings, so as to offset the economic advantages. If this happens, the plan should be cancelled, and the more economical design plan should be considered.
Note: If mainline cables are involved, relevant costs and design specifications should also be included.
3. The design points of the building group subsystem
1. Multi-mode or single-mode outdoor optical cable should be used as the backbone cable of the building group data network.
2. When the main cable of the building group data network needs to be connected to the telecommunications public network by using optical cables, single-mode optical cables should be used, and the number of cores should be determined according to the needs of integrated communication services.
3. The trunk cables of the building group should be laid in the form of underground pipelines. Spare pipe holes should be reserved during the design for expansion.
4. When using direct burial, the cable is usually 60.96cm below the ground or according to local regulations.
4. Cable laying method in building group subsystem
method | advantage | Disadvantages |
Overhead cable routing | If you already have a telephone pole, the cost is the lowest | No mechanical protection is provided; |
Directly buried cable wiring | Provide some level of institutional protection; | The cost of trenching is high; |
Cable routing in pipes | Provide the best institutional protection; | The cost of digging trenches, opening pipes and entering holes is very high; |
Cable routing in the tunnel | Protect the appearance of the building, if there is a tunnel already, the cost is lowest and safe; | The heat dissipated by the gas supply, water supply or heating pipes or leaking hot water will damage the cable, |
The various permits required for directly buried cables should be properly kept so that they can be used immediately during construction.
The items that need to apply for a permit are as follows:
1) Dig the street pavement; (Urban construction) 2) Close the access road; (Traffic) 3) Stack the materials on the street; (Urban management) 4) Use explosives; (Public security) 5) Push the steel pipe under the street and railway; Urban construction) 6) The cable crosses the river. (River Affairs)
4.9 Electrical protection, grounding and fire protection
1. Grounding design
The composition of the grounding of the integrated wiring system: including the grounding wire, grounding bus (layer grounding terminal), grounding trunk, main grounding bus (total grounding terminal), grounding lead, and grounding body. The above 6 elements are designed in layers.
3. Electrical protection
The purpose of electrical protection: to minimize damage to cables and related connectors of integrated wiring caused by electrical faults; to avoid damage to terminal equipment or devices connected to integrated wiring by electrical faults
Types of electrical protection: overvoltage protection, overcurrent protection.
The communication equipment of modern communication systems generally adopts dual protection of overvoltage and overcurrent.
When the outdoor cable enters the room, it usually enters the room after a switch at the building entrance. Electrical protection devices should be added at the transition points. These devices are usually installed on the wall surface of the cable entrance to the building. In large buildings (groups), dedicated rooms can also be set up.
LSZH cables is the abbreviation term of (low smoke halogen free) low smoke zero halogen electrical cables.FR is for flame retardant power cables, also for the short term of Fire Resistant Power Cables. The smoke released by these cables is non-toxic when fire happens. Therefore they are applicable for public places to protect instruments, equipments and people from potential harm.Fire resistant power cable will still keep the electrical power on within certain time in case of combustion.Flame retardant power cable may produce low gases and smoke after combustion.These cables are generally used in population-concentrated public places to have better fire safety and rescue capability.
Specification
Conductor:99.99% oxygen free copper or aluminum
Insulation/Sheath: LSZH FR formula added
Rated Voltage:≤35KV
Packaging: wooden steel drum, wooden/paper/plastic reels
Main advantage
l Low or no halogen acid gas release
l Excellent resistance to weather (-30℃ to 105℃)and fire
l Withstanding high voltage and current stressing
l Good elasticity and stickiness, long life time
Application
l High-rise building
l Hospital , Large-scale library,Gym ,Hotel
l Bus station or railway station, Airport , passenger waiting room
l Cultural heritage building, nuclear power plant,important military facilities
l Subway ,underground shopping mall
Classification
The application of LSZH power cables are classified into 4 level based on using features, fire risk and difficult for evacuation and life-saving.
|
Application |
Flame Retardant Class Choice |
|
Superior |
Class A |
|
Grade 1 |
Class B |
|
Grade 2 |
Class C |
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.
Please welcome to get in touch with us for further information about catalogue, production and price list. Will response as soon as possible. OEM service is available based on legal authorization. And you are also very welcome to visit our factory by mutual schedule check accordingly.
LSZH FR Power Cable,Lszh Fr Sheath Power Cable,Power Station Control Cable,Low Smoke Control Cables
Smartell Technology Co.,Ltd , http://www.liencable.com