Integrated wiring four types of optical cable indoor wiring

Integrated wiring system came into being

Buildings pursue integrated, intelligent, broadband, and personalized information and communication networks, and the integrated wiring system (PDS) came into being. With the rapid development of FTTB and FTTH technologies, indoor optical cables have been more and more widely used in building integrated wiring systems (including horizontal and vertical wiring systems).

Due to the special environment of indoor applications, indoor optical cables must meet the requirements of toxicity, corrosion and low smoke in international standards while maintaining very good flame retardancy, mechanical properties and light transmission properties. The lifting of optical cables between floors in vertical systems, the narrow space application of communication cabinets in horizontal systems, the application of optical fibers to the desktop, and the application of communication through high-pressure air-filled spaces all put forward different requirements for indoor optical cables. How to choose the right optical cable to meet the needs of different indoor applications?

Indoor optical cable should choose tight-buffered optical fiber

At present, most indoor optical cables use tight-buffered optical fibers or single-core cables as the basic unit, reinforced by aramid yarns, and flexible optical cables with flame-retardant or non-flammable sheaths. There are also plastic optical fibers used as indoor wiring cables, but this product has not been widely used.

Advantages of the tight-sleeve fiber design: the tight-sleeve is integrated with the fiber, providing good mechanical protection, so that the fiber exhibits good compression and bending resistance during termination; good flexibility and toughness, small bending radius ; Good environmental protection, improve the service life of the fiber; Excellent moisture resistance; Tight buffer layer is easily stripped to the fiber core; Compatible with all standard types of connectors; Simplified termination procedures and reduced termination costs.

Compared with the loose tube design, the loose tube uses ointment to buffer and moisture-proof the optical fiber, and the ointment has no fire resistance. This is far from meeting the indoor fire safety requirements. Moreover, the flame spreads along the fiber optic cable, extending the damage to the fiber optic cable deep into the wall and into the pipe. During installation, a large amount of cleaning materials and a large amount of grease cleaning time are required. At the same time, a connection method is required, and the material cost is greatly increased. The tight-buffered fiber design and flame-retardant or non-flammable jacket of the indoor optical cable make the indoor optical cable fully meet the requirements of indoor safety applications.

The outer protective materials used for indoor optical cables include PE, PVC, polyurethane, low smoke halogen free material, flame retardant PE, etc. Indoor optical cables with different outer sheathing materials can be used in environments with different requirements. Therefore, indoor optical cables with tight-buffered optical fiber design are generally used in indoor high-performance communication transmission applications.

Integrated wiring optical cable

Application and Selection of Indoor Optical Cable

(1) Vertical lift optical cable (Riser)

After the optical cable enters the building, it is necessary to provide the connection between the entrance equipment, the equipment room or the computer room and the communication cabinets on different floors, which is called "vertical wiring system". At this time, the wiring optical cable is mostly located in the vertical pipe (Riser) of the shaft between floors. For this reason, the optical cable needs to withstand a greater tensile force (maximum self-weight).

(2) Single-core, dual-core interconnecting indoor optical cable (Interconnect cable)

Tight-sleeve single-core, tight-sleeve 8-core double-core, tight-sleeve 2-core to 4-core circular structure indoor optical cable. Because the tight-sleeve structure with very good flexibility and high-load aramid yarn are used to surround the tight-sleeve optical fiber, the cable structure size Small size, good flexibility, can withstand a small bending radius, no inventory traces, fiber to workstation, patch cords, pigtails, patch cords in communication cabinets, communication cabinets to indoor wall terminals, and terminals to transceiver applications Ideal for interconnecting fiber optic cables. They directly carry standard connectors, and play the role of interconnection between optical end devices and trunk (vertical) optical cables in communication cabinets, distribution boxes, protection boxes, and equipment boxes. This type of optical cable is convenient and easy to install in a limited space, and becomes an ideal network cable solution for limited space wiring and flexible cords in buildings.

(3) Optical cable for inflatable environment (Plenum)

In indoor applications, Plenum grade indoor cables are required when the cables need to pass through transmission ducts, high pressure plenums or air handling systems to transmit information. This special use environment puts forward more stringent requirements on the flame retardancy and corrosion resistance of the optical cable. Therefore, the tight sleeve material and outer sheath material of the indoor optical cable used are more strict, the tight sleeve is PVC material, and the outer sheath material is UL certified PVC material with flame retardant added or hard fluoropolymer. Engineered with PVC over fluoropolymers. Because PVC is soft, easy to bend, and has no inventory traces, it can be stored in a circle.

(4) Anti-rodent optical cable

Single-core or multi-core tight-buffered fiber optic cables protected by stainless steel hoses have strong lateral pressure resistance, bending resistance, high tensile strength, and excellent anti-rat performance. It can be used in situations where trampling occurs, such as under carpets or where limited space requires frequent bending or rodent infestation.

In addition, there are several matters: First, when the optical fiber ribbon cable is used to enter the building, the matching indoor optical fiber ribbon cable (fiber ribbon + aramid yarn + PVC sheath structure) can be selected. Second, when laying underground pipes and ceilings in equipment rooms, reinforced structures can be used. For example, PE or PU sheaths can be used on the basis of distribution cables, or aluminum-PE sheaths can be used on the basis of scattered cable structures. set structure, etc. Third, when the distribution cable adopts metal armored sheath, it can be used for overhead and direct buried laying. Fourth, low smoke halogen free (LSZH) materials can be used as the outer sheath in occasions with high requirements on toxicity and smoke emission. Fifth, the PU sheath has better resistance to friction, scratches and chemical erosion, and can be used for emergency, emergency repair and military optical cables.

Vertical lift fiber optic cable

The distribution cable is composed of multiple tight-sleeved optical fibers, reinforced by aramid yarns, and the indoor optical cable with PVC outer sheath is suitable for indoor wiring, and can be used as pigtails, jumpers and transmission lines between devices. It starts from the basement and rises along the riser between floors. After reaching the protection box of the floor distribution frame, it is plugged into the box panel through pigtails, and then connected to the terminal equipment through a double-ended patch cord with a standard connector. The cable has very good flexibility and is easy to work in a communication cabinet. When PE jacketed, the cable can also be used in inter-building brackets and ducts.

Breakout cable (Breakoutcable)

It is an indoor optical cable with a PVC outer sheath that is twisted by multiple single-core cables (sub-cables). Its characteristic is that each sub-cable (reinforced with aramid yarn) provides good protection for the optical fiber, and each sub-cable does not need to enter the protection box and can be directly branched for use. It starts from the basement and rises along the riser between floors. After reaching the floor equipment box, each sub-cable is directly connected to the equipment through the connector. The cable can also be placed horizontally on the ceiling of the computer room.

Subgroup cable (Subgroupcable)

Multiple sub-cable groups (distribution cables) are twisted into cables. The biggest feature of the indoor optical cable of sub-cable group with PVC outer sheath is that each sub-cable group can be branched for use, and each sub-cable group enters a different protection box on the floor. Each protection box corresponds to a different indoor work area. When there are hybrid fibers in the cable, the multimode fibers and single mode fibers can be effectively distinguished and used separately by placing them in different sub-cable groups. When the optical cable needs to be directly connected to the terminal equipment across the protective box, a structure composed of single-core cable groups is also used, which provides better protection for the optical fiber.

The four types of optical cables for indoor integrated wiring have been introduced to you. I hope you have mastered and understood them. We will continue to introduce relevant knowledge to you in future articles.