ABSTRACT
The optical fiber is usually covered by plastic to prevent corrosion due to scoring and moisture on the surface. The plastic-covered fiber is subject to various types of mechanical stress during the production process, during and after installation. The center type is used widely in optical fiber cable and the armored type for a cable with a large number of fibers. For a single-fiber cable, fibrous strength members are very often stranded on the plastic-coated fiber. The sheath of the optical fiber cable may be regarded as equal in basic construction to the sheath of a conventional telecommunications cable. The representative methods of construction of optical fiber cable core are roughly classified according to the following types: ribbon, stranding layer unit, loose tube, and V-groove. The water-blocking cable needs to sense penetrating water inside, which can be handily made available in a communications cable by monitoring interconductor insulation resistance.
