光纤收发器故障的排除及光缆质量的判断（Trouble shooting of optical fiber transceiver and quality judgment of optical fiber cable）

光纤收发器故障的排除及光缆质量的判断（Trouble shooting of optical fiber transceiver and quality judgment of optical fiber cable） 光纤收发器故障的排除及光缆质量的判断(Trouble shooting of optical fiber transceiver and quality judgment of optical fiber cable) First, according to the following steps to find fault exclusion: (a), first look at the lights or light optical transceiver module and UTP port indicator is flashing? A, such as the optical transceiver (FX) indicator light does not shine, please confirm whether the fiber link cross links? A fiber jumper is parallel connected; the other end is connected with the cross. B, such as A optical transceiver (FX) indicator lights, B optical transceiver (FX) indicator light does not shine, then the fault in the A transceiver: one possibility is: A transceiver (TX) optical transmission has been bad, because the B transceiver interface (RX) to receive the optical signal; the other one possibility is that the A transceiver (TX) of the optical fiber link to send port problems (cable or light jumpers might be broken). C, twisted pair (TP) indicator light does not shine, please confirm whether the wrong or twisted pair wiring connection error? Please use the on-off tester (though some twisted pair transceiver indicator to connect optical fiber link after the light). D, some of the transceiver has two RJ45 ports: (To HUB) said the connection line between the switches is straight line; (To Node) said the connection line is connected with the switch is the intersection line. E, some MPR transceiver side switch: said connection line is connected with the switch is straight line mode; DTE switch: switch is connected to cross line. (two), optical fiber, optical fiber jumper has been broken? A, cable on-off detection: using laser flashlight, solar light, light to one end of the cable connector or coupling light; at the other end to see whether there is a visible light? If there is no visible light show cable fault. B, optical fiber line on-off detection: laser flashlight, sun light at the head of a fiber jumper light; at the other end to see whether there is a visible light? If there is a visible light indicates that the optical fiber jumper is not broken. (three), half / full duplex mode is wrong? Some have said FDX transceiver side switch: full duplex switch; HDX: half duplex. (four) instrument, optical power meter detection optical transceiver or optical module under normal conditions of light power: -10db--18db; single mode multimode: 20 km: -8db--15db; -5db--12db; 60 km single mode: if the light output power of optical transceiver in -30db--45db, you can judge the transceiver. Several method of identification of cable quality, skin: Indoor cables generally use polyvinyl chloride or flame retardant polyvinyl chloride, surface should be smooth, shiny, flexible, easy to peel. Inferior cable jacket finish is poor, easy and tight, aramid adhesion. PE should adopt high-quality outdoor cable sheath black polyethylene cable, skin smooth and bright, uniform thickness, no bubble. Inferior cable's skin using recycled materials production, the cable skin rough, because the raw material has many impurities, can be found at the cable jacket with a lot of very small pit laying wow, after a period of time will crack and seepage. Two, fiber production enterprises generally use a regular cable core manufacturers, some low-quality cable usually use C and D class of optical fiber and optical fiber smuggling unknown, the optical fiber due to complicated sources, the factory has a long time, often damp discoloration, And the multimode fiber also often mixed with the single-mode fiber, and the general lack of small plant detection equipment must be, cannot judge the quality of optical fiber. Because of the naked eye can not distinguish the fiber, touch to problems in construction is that the bandwidth is narrow, short transmission distance; uneven thickness, and not lack of fiber pigtail docking; flexibility, when a broken fiber disc. Three, strengthen the outdoor cable wire: formal manufacturers of steel wire after phosphating treatment, the surface is gray, so the wire cable does not increase the hydrogen loss, no rust, high strength. Inferior cable and replace the wire or aluminum wire for general use, identification method is very easy - looks white, pinch in the hands can be bent. With hydrogen cable wire production loss such that for a long time, both ends of the hanging fiber box rust fracture. Four, steel armor: formal manufacturers using double-sided brush rustproof paint bandage strip longitudinal lines, inferior cable is used in ordinary iron, usually only one side made anti rust treatment. Five, loose tube: loose tube cable with optical fiber should be used PBT materials, such as high casing strength, no deformation, anti aging. Inferior cables usually use PVC material production casing, the outer diameter of the sleeve that is very thin, hand pinch flat, like Straw beverage. Six, fiber paste: Outdoor cables within the fiber paste can prevent fiber oxidation, because water vapor into the damp, inferior fiber fiber paste with a few, seriously affected the life of fiber. Seven, also known as: Aramid Kevlar, is a kind of high intensity chemical fiber, at present in the industrial, military helmet, bullet proof vest is the material production. Currently the world's only DuPont and Holland Akesu production, the price is about Sanshiduowanyi tons. Indoor cable and overhead power cable (ADSS) are used as reinforcement of aramid fiber, aramid fiber because of high cost, poor indoor cable diameter generally do very small, this can be reduced by a few strands of aramid cost savings, such cables easily when wearing tube pulled off. ADSS cable is a cable to determine aramid use shares according to the span, second wind speed, before construction must be carefully examined and confirmed. Cable fault summary and other dust pollution is the main enemy of cable data transmission, especially those of high speed network. Gigabit Ethernet standard for optical link loss margin is only 2.38dB, very small impurity can cause serious influence. Simply check the connector to the cleanliness and use dustproof cover (sets) can effectively protect the connector from pollution. However, in cable fault diagnosis when the appropriate test tools, such as video magnifier, OTDR, can greatly shorten the time of fault diagnosis, so as to shorten the network failure time, reduce the loss due to network interruption.