I. Identification from the outer skin
Indoor optical cable is generally made of polyvinyl chloride or flame retardant polyvinyl chloride. The appearance should be smooth, bright, flexible, and easy to peel off. The outer skin of inferior optical cable has poor finish, and it is easy to stick to tight sleeves and aramid.
The PE sheath of the outdoor optical cable should be made of high-quality black polyethylene. After the cable is formed, the sheath is flat, bright, uniform and thick, and free of bubbles. The outer sheath of inferior optical cable is generally produced using recycled materials. The outer skin of this optical cable is rough. Due to the many impurities in the raw material, it can be found that there are many very small pits in the outer sheath of the optical cable, which will crack and leak after a period of time.
Second, from fiber identification
Formal optical cable manufacturers generally use large-scale A-grade cores, and some low-quality and low-quality optical cables usually use C-, D-grade optical fibers and smuggled optical fibers of unknown origin. These optical fibers often have tide due to their complicated sources and long delivery time. Discoloration, and single-mode fiber is often mixed in multi-mode fiber. Generally small factories lack the necessary testing equipment and cannot judge the quality of the fiber. Because such optical fibers cannot be discerned by the naked eye, common problems encountered during construction are: narrow bandwidth and short transmission distance; uneven thickness, which cannot be connected with pigtails; optical fibers lack flexibility, and break when they are bent.
Third, from strengthening wire identification
The steel wires of outdoor optical cables from regular manufacturers are phosphated and the surface is gray. Such steel wires do not increase hydrogen loss, rust, and have high strength. Inferior optical cables are generally replaced by thin iron or aluminum wires. The identification method is easy-the appearance is white, and it can be bent freely when pinched in the hand. Optical fiber cables produced with such steel wires have large hydrogen losses and long periods of time, and the two ends of the fiber optic box will rust and break.
