I. Procurement Standards

(1) According to national standards, a certificate of quality system certification and a product qualification certificate shall be provided; the markings printed on the surface of the wires shall be clear and evenly spaced; the packaging reels shall be neatly arranged and in good condition, and the wires shall be smooth and flat.

(2) The conductor wire gauge shall match the cross-sectional area specified on the certificate of conformity. Depending on the power rating of the electrical appliance, wires of the appropriate gauge should be selected. The surface of the wire core should be bright and smooth, free of burrs, with tightly twisted strands that are evenly compacted, soft yet resilient, and not easily broken.

(3) There are three main series of electronic wires currently available on the market: UL-standard, 3C-standard, and VDE-standard. Wires measured in AWG typically conform to the UL standard, while those measured in square millimeters generally comply with either the 3C or VDE standard. Among domestic electronic wire manufacturers, the 3C and UL standards are the primary ones adopted.

(4) Communication cables include local communication cables, long-distance symmetrical cables, coaxial cables, submarine cables, and others. The selection of these cables should be based on their intended use and application scope.

(5) Based on the mode of signal transmission in optical fibers, they are broadly classified into two major categories: single-mode and multi-mode. Single-mode fibers are primarily used in medium- and long-distance signal transmission systems, such as fiber-to-the-home networks, subways, and long-distance road networks. Multi-mode fibers, on the other hand, are mainly used for short-distance network transmissions. In local area network projects, the optical fibers typically employed are multi-mode fibers, which can be further categorized into indoor and outdoor types, as well as single-core and multi-core variants. Indoor cables have at least four cores per strand, while outdoor cables have at least six cores per strand.

II. Wiring Specifications

(1) Before construction begins, thoroughly consider the electrical and lighting equipment required for each functional area, and use this as a basis to roughly calculate the appropriate wire gauge for each circuit. Whenever possible, use high-quality copper-core sheathed wires and concealed junction boxes to prevent aging and breakage, which could otherwise make panel installation difficult.

(2) Draw circuit distribution diagrams for each room, and mark the coordinates and heights of various lighting fixtures, switches, outlets, and distribution panels to determine the routing paths and branch connections. It is best to use wires of different colors to easily identify different circuits.

(3) It is best to route power cables through flame-retardant conduits before installation. In ceilings made of combustible materials, flame-retardant conduit runs must be installed. Additionally, a power switch should be provided outside the ceiling, enabling the power to be disconnected when necessary. All wire connections must be made within junction boxes.

(4) The total capacity of each branch circuit in indoor wiring should not exceed 3,000 watts; the load current of each single-phase circuit should generally not exceed 15 amperes. When using high-capacity household appliances such as air conditioners, a dedicated line should be provided.

(5) Primarily adopt multi-circuit wiring based on functional requirements, while taking into account specific home decoration conditions and fire safety regulations, ensuring compliance with safety principles and flexibly selecting practical wiring solutions.

(6) The A end of all-plastic indoor communication cables shall be marked with red; it is customary to seal this end with a red cap or wrap it with red tape, and the A end must face the central office. The other end, designated as the B end, shall be marked with green; it is customary to seal this end with a green cap or wrap it with green tape, and it must be securely fastened within the cable reel. The cable twisting direction shall be counterclockwise, and the outer end must face the user.

(7) When bending optical fibers, the bending radius should be more than 20 times the fiber’s own diameter. The length of a single cable run should not be too long (typically no more than 2 km). During cabling, start pulling from the middle and extend outward in both directions. When optical fibers are used in backbone networks, each floor distribution room should be equipped with at least a 6-core optical cable; for advanced applications, it is best to use a 12-core optical cable. This recommendation takes into account three aspects: application requirements, backup considerations, and scalability.