It is suitable for the installation of building weak current and building integrated wiring system.
Second, the construction preparation
2. 1 technical preparation
See article 2 1. 1 of "Installation of telephone sockets and junction boxes".
2.2 Material and equipment requirements
1. Transmission part: twisted pair, optical cable, optical fiber connector, optical fiber coupler, etc.
2. Computer room: junction box, cabinet, various distribution frames, wiring modules, jumpers, etc.
3. Terminal part: information socket, rice fiber socket, 8-bit modular universal socket and multi-user information socket.
4. The specifications, models and quantities of the above-mentioned equipment and materials shall meet the design and contract requirements, and shall be accompanied by the ex-factory quality inspection certificate, performance inspection report and CCC certification mark. The contents of signs and labels attached to cables shall be complete and clear.
5. Galvanized materials: galvanized steel pipes, galvanized trunking, metal expansion bolts, metal hoses and grounding bolts.
6. Other materials: junction box, ground socket, plastic trunking and its accessories. The environmental temperature of the place where the plastic trunking is laid shall not be lower than-15℃, and its flame retardant oxygen index shall not be lower than 27%.
2.3 Main machines and tools
1. Installation tools: pipe stewing machine, hydraulic hole opener, threading machine, hacksaw, electrician combination tool, nail gun, rivet gun, hand electric drill, bench drill, high stool, etc.
2. Test instruments: network tester, optical time domain reflectometer, multimeter, megger, pencil, tape measure, $XF ruler, string, wire pendant, etc.
3. Special tools: wire stripper, wire pressing tool, optical fiber welding machine, microscope, cutter, glass grinding disc and drying box.
2.4 Operating conditions
1. Cable trench, trough, pipe, box and box are completed.
2. The civil decoration project is completed and all lines are connected.
3. The ambient temperature, humidity and illuminance between the wiring room and the equipment room should meet the design requirements, with good ventilation, no dangerous goods indoors and complete fire fighting equipment.
Third, the construction technology
3. 1 process
3.2 Operation process
1. Pipeline laying
See article 2 1. 1.3.2, paragraph 1 of "Installation of telephone sockets and junction boxes".
2. Cable laying
(1) When the underground communication pipe network is used for the pipeline, it shall comply with the relevant provisions in the current national standard Technical Code for Construction and Acceptance of Communication Pipeline Engineering (YDJ39).
(2) Cable laying shall generally meet the following requirements:
1) Cable laying shall be natural and straight, and cables shall not be twisted or crossed.
2) The cable should not be squeezed by external force, and the surface in contact with the cable should be smooth to avoid cable deformation and damage.
3) Before laying, both ends of the cable shall be labeled, indicating the starting and ending positions, and the labels shall be legible.
4) Twisted-pair cables, optical cables and cables of other weak current systems in the building should be laid separately, without joints in the middle.
5) After the cable is terminated, there shall be allowance. The reserved length of twisted-pair cable between handover room and equipment room is generally 0.5m ~ lm, and the working area is10mm ~ 30mm. The reserved length of optical cable at the equipment end is generally 3m ~ 5m. If there are special requirements, the length should be reserved according to the design requirements.
6) The bending radius of the cable shall meet the following requirements:
① The bending radius of twisted-pair cable should be more than 8 times of the cable outer diameter.
② The bending radius of trunk twisted-pair cable should be at least 10 times of the cable outer diameter.
(3) The bending radius of the optical cable shall be 20 times greater than the outer diameter of the optical cable.
7) When towing and laying large logarithmic cables and optical cables, special cable towing ends shall be made.
8) When laying optical cable, the rotation of optical cable drum should be synchronized with the laying of optical cable, and the traction speed of optical cable is generally 10m/min.
9) The traction of laying cables should be less than 80% of the allowable tension of cables, and the instantaneous maximum traction of optical cables should not exceed the allowable tension of optical cables. The main traction should be added to the reinforced core of the optical cable.
10) The minimum clear distance between twisted-pair cable and power cable shall comply with the provisions of Table 2 1- 10, and the minimum clear distance between twisted-pair cable and other pipelines shall comply with the provisions of Table 21-1.
(3) Cable laying in ground trunking and concealed pipes shall meet the following requirements:
1) Both ends of laying pipeline shall be marked with adhesive tape.
2) The concealed piping shall be made of steel pipe or flame-retardant hard (PVC) plastic pipe. When laying twisted-pair wires with concealed pipes, the cross-sectional utilization rate of the pipes should be 25% ~ 30%.
3) The ground trunking adopts metal trunking, and the cross-sectional utilization rate of trunking shall not exceed 40%.
4) For pipes laid with steel pipes, more than two 90 bends should be avoided (otherwise electric conduits should be added), and the bending radius should be greater than 6 times the pipe diameter.
(4) Installation of cable tray and laying of cables in trunking shall meet the following requirements:
1) The distance between the top of the bridge and the ceiling or other obstacles should not be less than 300mm, and the utilization rate of the internal section of the bridge should not exceed 50%.
2) When the cable is laid vertically in the cable tray and trunking, the cable shall be fixed on the support frame in the tray at the upper end of the cable with a spacing of1.5m; When laying horizontally, the cable should be straight and try not to cross, and fixed points should be set at 300mm on both sides of the inlet and outlet trunking and corner.
3) When laying cables in horizontal and vertical bridges and vertical trunking, they should be bundled. 4 pairs of twisted cables are bundled in 24 pairs, and 25 or more pairs of trunk twisted cables, optical cables and other cables are bundled according to cable type, cable diameter and cable core number. The binding spacing shall not be greater than 1.5m, and the binding spacing shall be even and moderately elastic.
(5) The laying of cables with exposed pipes, bridges and metal trunking in the shaft shall meet the requirements of the above related clauses. A 50mm waterproof platform should be set around the floor hole in the shaft, and the hole should be blocked with fireproof materials.
(6) The technical requirements for laying cables and optical cables with overhead pipes, directly buried pipes, exposed pipes (troughs) or concealed pipes (troughs) in the subsystem of the building complex shall be implemented in accordance with the relevant provisions of the current national standards "Technical Specification for Construction and Acceptance of Local Telephone Line Engineering" (YDJ 38) and "Provisional Technical Regulations for Construction and Acceptance of Optical Fiber Digital Transmission System Engineering in Telecommunication Network" (YDJ 50).
3. Equipment installation
(1) cabinet installation
1) Locate the cabinet according to the layout of the computer room, make the basic channel steel, and install the cabinet firmly on the channel steel foundation.
2) After the cabinet is installed, the verticality deviation should not be greater than 2 1m and the horizontal deviation should not be greater than 2mm；; The flatness deviation at the top of rows of cabinets should not be greater than 4 mm.
3) Various parts on the cabinet should not fall off or be damaged. If the paint surface falls off, it should be repainted with complete and clear signs.
4) There should be an operating space of 1.5m in front of the cabinet, and the distance from the back of the cabinet to the wall should not be less than 1m to facilitate operation and maintenance.
5) The distance between the bottom of the wall hanging box and the ground should meet the design requirements. If there is no requirement in the design, the installation height should be1.4m.
6) When installing equipment in the cabinet, there should be enough clearance between the equipment to ensure air circulation and help the equipment dissipate heat.
(2) Installation of distribution frame
1) When the outlet mode is adopted, the bottom position of the distribution frame should correspond to the cable inlet hole.
2) The verticality deviation of each in-line distribution frame shall not be greater than 2mm.
3) All terminal signs shall be complete.
(3) Installation of various wiring components
1) All components shall be intact, installed in the correct position and marked completely.
2) The fixing screws should be tightened, and the panel should be kept on a horizontal plane.
(4) Grounding requirements
The grounding resistance of installation cabinets, wiring equipment, metal steel pipes and trunking grounding bodies shall not be greater than1Ω, and the section and color of grounding conductor shall meet the requirements of the specification.
4. Cable termination
(1) General requirements for cable termination:
1) Before the cable is terminated, the tag number must be checked and terminated in sequence.
2) Cable terminals must be firmly clamped and in good contact.
3) Installation of cable terminal shall meet the requirements of design and installation manual of product manufacturer.
(2) The end connection of twisted-pair cable and connecting hardware shall meet the following requirements:
1) Use special wire stripping pliers to strip the cable sheath. Be careful not to scratch the insulation layer, and each pair of stranded wires should be twisted as much as possible. The untwisted length should not be greater than13mm; For Category 5 wires; Class 4 line should not exceed 25mm. Stranding and crossing between stranded wires should be avoided.
2) When the twisted pair is connected to the 8-bit modular universal socket (PJ 45), it must be clamped in the order of color code and twisted pair, and then terminated with a special wire pressing tool. The type, color code and quantity of sockets shall conform to the provisions in Figure 2 1- 16.
3) When the twisted pair is connected with the clamping terminal of RJ45 8-bit modular universal socket, it should be clamped in the order of near first, then far, and then down first.
4) The shielding layer of twisted pair cable must be in reliable contact with the shielding cover at the connector terminal, and the cable shielding layer should be in 360 circumferential contact with the shielding cover of the connector, and the contact length should not be less than lOmm.
(3) The core end of optical cable shall meet the following requirements:
1) The fusion joint of optical fiber should be protected, and connectors should be used to facilitate optical fiber jump connection.
2) The junction box panel shall be marked.
3) The movable connector of optical fiber jumper should be cleaned before inserting the adapter, and the insertion position should meet the design requirements.
4) The average loss value of optical fiber welding is 0. 15dB, and the maximum value is 0.3dB ..
(4) termination of various jumpers
1) All kinds of jumpers and plug-ins have good contact, correct wiring and complete signs. The jumper type should meet the design requirements.
2) The lengths of all kinds of jumpers shall be determined according to the site conditions. Generally, the twisted pair is less than 5m, and the optical cable is less than lorn.
5. System debugging
(1) The test of integrated wiring system includes the electrical performance test of cable system and the performance test of optical fiber system. See article 7.0. 1 of the current national standard "Code for Acceptance of Building and Building Integrated Wiring System" (GB/T 503 12) for the test record. Usually, test instruments have the function of storing test records and can automatically output printed records.
(2) The electrical performance tester shall meet the requirements of Table 2l- 12 according to the secondary accuracy.
(3) Cable and optical cable testing instruments can only be used in engineering after they have been calibrated by the metrological department and obtained the certificate of approval.
(4) The tester shall be able to test the wiring system and optical fiber links of Category 3 and Category 5 twisted-pair cables.
(5) The electrical performance test time of the information socket tester should be between 20 ~ 50s.
6. Completion acceptance
(1) The system engineering acceptance shall be checked according to the items listed in Appendix A of the current national standard {Code for Acceptance of Building and Building Integrated Wiring System} (GB/T503 12), and the unqualified items shall be rectified in time.
(2) If the system engineering is managed and maintained by computer, it shall be accepted as a special project.
Fourth, quality standards.
4. 1 main project
1. Inspection requirements for cable laying and termination:
The following items shall be tested, and the test results shall meet the provisions of 5. 1. 1, 6.0.2 and 6. O.3 in the current national standard Code for Acceptance of Building and Building Integrated Wiring System (GB/T 503 12):
(1) Bending radius of cable.
(2) Laying of embedded trunking and concealed pipes.
(3) The power cord and cables of the integrated wiring system should be laid separately, and the minimum clear distance between cables should meet the design requirements.
(4) The laying of concealed pipes of electric power and optical cable in the building and the minimum clear distance with other pipelines.
(5) twisted pair cable core termination.
(6) Optical fiber connection loss value.
2. The subsystem of the building complex adopts overhead, pipelines and directly buried power and optical cables, which shall comply with the relevant provisions of the acceptance of the local network communication line project.
3. The installation and inspection of cabinets and distribution frames shall meet the following requirements in addition to the provisions in paragraphs (4) and (3) of Article 2 1.6.3.2:
(1) The color code of a single cable in the connection module of distribution frame should be consistent with that of cables, and a large number of cables should be classified according to the combination regulations of standard chromatography.
(2) The wiring sequence and arrangement of the distribution frame terminated at RJ45 port shall be terminated according to T568A or T568B termination standard, but the same standard as the wiring sequence arrangement of the information socket module must be used.
4. When the information socket is installed on the raised floor or ground, the junction box shall be strictly waterproof and dustproof.
5. The lightning protection grounding resistance value should meet the design requirements, and the section and color code of the metal shell of the equipment and device and the cable shielding grounding wire should meet the design requirements; The connecting conductor of grounding terminal shall be firm and reliable.
6. Special test instruments should be used to test the performance of all links of the integrated wiring system, including engineering electrical performance test and optical fiber characteristics test, and the signal transmission technical indicators of the system should meet the design requirements.
4.2 General projects
1. Cable end connection shall comply with the provisions of Article 2 1.6.3.2 (1), paragraph 4.
2. The terminal connection of all kinds of jumpers shall comply with the provisions of Paragraph 4 of Article 2 1.6.3.2.
3. The installation of cabinets and distribution frames shall meet the following requirements in addition to (1 .6.3.2, paragraph 3) and (2):
(1) The cabinet should not be directly installed on the raised floor. The base should be made according to the size of the bottom surface of the equipment. The base shall be directly fixed on the ground, and the cabinet shall be fixed on the base. The height of the base should be the same as that of the raised floor, and then the raised floor should be laid. The horizontal error of the base should not be greater than 2mm per meter.
(2) The backboard jumper frame shall be installed on a reliable wall through the supporting metal backboard and wiring management frame, and the metal backboard shall be fastened to the wall.
(3) The bottom of the closet should not be less than 300mm from the ground.
(4) The bridge or trunking shall directly enter the rack or cabinet.
(5) All terminal signs shall be complete.
4. The installation requirements of information sockets shall comply with the provisions of Article 4.0.3 of the current national standard "Code for Acceptance of Building and Building Integrated Wiring Engineering" (GB/T503 12).
5. The junction box panel of the optical fiber core terminal shall be marked.
6. When using computer to manage and maintain the integrated wiring system, the test results of the following contents shall meet the design requirements:
(1) Chinese platform and system management software.
(2) Show all hardware equipment and floor plan.
(3) Display the component positions of trunk subsystem and wiring subsystem.
(4) Real-time display and login the working status of various hardware facilities.
Verb (abbreviation of verb) finished product protection
1. When installing system equipment, the building shall not be damaged, and the wall surface shall be kept clean.
2. When installing cables and trunking in the ceiling, the keel and ceiling shall not be damaged.
3. Necessary protective measures should be taken for the installed equipment to prevent damage and pollution. Waterproof measures should be strengthened at the exit of ground trunking.
Six, should pay attention to the quality problems
1. The protection of embedded pipes and boxes should be strengthened, and protective cover plates should be installed in time to prevent pollution from blocking pipes or ground trunking.
2. Before construction, check whether the cable length is correct according to the drawings, and adjust the signal frequency to make its attenuation meet the design requirements, so as to avoid serious signal attenuation.
3. Check the color code in strict accordance with the construction drawing during construction to prevent the system from working normally due to wiring errors.
4. The cable shielding layer should be reliably grounded, and different kinds of cables in the same trunking should be shielded by clapboards to prevent signal interference.
Seven, environment, occupational health and safety management measures
7. 1 Environmental management measures
See article 2 1. 1 of "Installation of telephone sockets and junction boxes".
7.2 Occupational Health and Safety Management Measures
1. In the process of handling equipment, not only should the equipment be guaranteed not to be damaged, but also people should be careful not to be injured.
2. The construction site should be cleaned up after completion, and the site garbage and waste should be piled up in the designated place, and cleaned and transported in time. It is strictly forbidden to throw it away at will.
3. The tools at the operator's hand should be conveniently placed in the tool bag, and it is forbidden to throw them around.
4. When measuring the optical cable with an optical power meter, it is forbidden to observe directly with the naked eye.