In the fiber-optic network, the fiber optic cable is a very important part. The fiber optic cable is comprised of a fiber optic core, reinforcing member, filler, and sheath. So, how is fiber optic cable classified?
1 Classification by the type of fiber used in the fiber optic cable
According to the type of fiber used in fiber optic cable, the fiber optic cable can be divided into single-mode fiber (SMF) and multi-mode fiber (MMF). The SMF is used for long-distance transmission and short-distance transmission. While the MMF is used for the short-distance transmission or the scenarios for accessing the network.
2 Classification by the cable core structure
According to different cable core structures, the fiber optic cable is divided into three types: unitube cable, stranded cable, and slotted core cable.
1) The loose optical fiber of unitube cable is placed in the center of the fiber optic cable without stranding because this position is the best one to reduce the loss caused by bending of the fiber optic cable. The reinforcing member of this cable can be two parallel high carbon steel wires placed parallel to the center tube in an outer sheath of black polyethylene. It can also be multiple low carbon steel wires spirally wound on a central tube.
2) The stranded cable is the one with tight or loose optical fiber spirally twisted on the central reinforcing member. Compared with the unitube fiber cable, the stranded cable requires a relatively complicated production process and equipment, it has a high number of fiber cores.
3) The slotted core cable is a fiber optic cable composed of a primary coated fiber or secondary coated tightly sheathed fiber lightly placed in the skeleton groove.
3 Classification by outer sheath structure
According to the different structures of the outer sheath, the fiber optic cable can be divided into unarmoured fiber optic cable, steel-tape armored fiber optic cable, and steel-wire armored fiber optic cable.
The difference of armored fiber optic cable is the mechanical strength, so it could be adjusted to different sceneries. For example, the steel-wire armored fiber optic cable would be used in the form of underwater laying to improve the mechanical property.
4 Classification by fiber optic cable material with or without metal
According to the fiber optic cable material with or without metal, the fiber optic cable can be divided into metal fiber optic cable and non-metal one. Metal fiber optic cable is composed of metal materials; while the non-metal fiber optic cables strengthening members, sheath are all plastic structure. It is featured with anti-electromagnetic interference, so it is suitable for strong current scenarios, such as power stations, electrified railways and strong electromagnetic interference zones.
5 Classification by number fibers.
According to the number of fiber cores, fiber optic cable can be divided into single-core fiber optic cable and ribbon (multi-core) fiber optic cable.
The structure of ribbon fiber optic cable is similar to the non-ribbon fiber optic cable, which is divided into three categories: unitube type, stranded type, and skeleton type.
6 Classification by fiber optic status
According to the secondary coating of optical fiber and the fiber core loose or tight status in the fiber optic cable, the fiber optic cable can be divided into tight-buffered cable, loose tube cable and semi-loose tube cable.
7 Classification by laying method
According to the different ways of laying fiber optic cable, fiber optic cable can be divided into aerial fiber cable, pipeline fiber cable, buried fiber cable, underwater fiber cable, submarine fiber cable, and air-blown fiber cable.
Due to the different ways of laying fiber optic cables, the mechanical characteristics proposed for fiber optic cables are different. The mechanical and temperature characteristics of fiber optic cable can be ensured by the structural design of fiber optic cable (selection of reinforcing members, sheathing and jacket structure, fiber residual length in fiber optic cable).
8 Classification by application
The classification of fiber optic cable could be carried out according to the usage sceneries, including the indoor, outdoor, indoor and outdoor, and others.
9 Classification by usage environment of fiber optic cable
According to the different special usage environments, the fiber optic cable can be divided into the fiber optic cable for high voltage transmission line, indoor fiber cable, emergency fiber cable and field operation fiber cable.
1) Since the optical fiber would not be interrupted by electromagnetism, it could be installed on a high voltage transmission line, which could be as a private network construction or a public network construction.
The fiber optic cables used in high voltage transmission lines are ADSS (All Dielectric Self Supporting), OPGW (Optical Ground Wire), and GWWOP (Ground Wire Wind Optical Cable).
2) Indoor fiber optic cable. The feature of indoor fiber optic cable is a small diameter, easy branching, good flexibility, convenient operation and wiring, and flame retardant. Most of them are used with tight tube optical fiber without filling the grease, or with non-metallic reinforcement components, they can be SMF and MMF. Besides, the fiber attenuation requirements are not high.
3) Emergency fiber optic cable and field operation fiber optic cable. These two cables are featured with small diameters, lightweight, and they can be released and retracted repeatedly and quickly. Usually, each roll of emergency fiber optic cable does not exceed 500m and some 100m per reel; each reel of field fiber optic cable is 2000m.
