[ Pobierz całość w formacie PDF ]
.frecording electrical activity as it occurs.The The procedure for connecting or splicinggrecorded values may or may not provide two sections of fiber is somewhat differentdetails about what is happening along the than for copper wire.hlines or on the network.For connectors, the fiber must be gluedScanners are much more sophisticated into a ferrule (a tube used for guiding theitesting tools.Some of the capabilities of top- fiber and for keeping it from moving), thenjof-the-line scanners include the following: the ends must be cut and polished in anappropriate manner.Polishing machines areCheck for faults (shorts or opens) in kused to make the fiber ends smooth, anda cable.special microscopes can be used to check thelTest a cable s compliance with any of polishing job.Even for  high-tech fiber-mseveral network architectures, such as optic connections, something as lowly asEthernet, Token Ring, ARCnet, and epoxy is needed to attach the fiber core tonelectronics standards, such as UL the side of a ferrule.o(Underwriters Laboratories).In addition, the same kinds of tools as forcopper wire may be needed: cable strippersMonitor performance and electrical pand pliers for taking the outer sheaths offactivity, given the type of cable andthe cable, crimping tools, and so on.Mostqarchitecture involved.fiber-optic installation kits also include arTest the cable s wiring sequence.duster (to make sure the pieces of fiber areclean before being joined).Special fluid maysGenerate and print a summary of thealso be used to adjust the reflectivity of theinformation obtained.fiber or cladding.tA powerful scanner can test for wire For splicing, the fibers are joined directlyuquality (for example, to find the best pair of and permanently.One way of doing thiswires in a cable for a connection), for the to fuse the two pieces of fiber together byvquality of the connections between cable applying heat to melt the fibers slightly andwsegments or between cable and device.then joining them before the fibers cool.At the lower end, scanners will at least be Special machines, called fusion splicers,xable to test for noise, crosstalk (in particular, are used to do this.Near End Crosstalk, or NEXT), signalyz 1022 TOP (Technical Office Protocol)Tools for Testing Fiber-Optic CableTHE  CARDWARE TOOLEquipment for testing the integrity of fiber-A useful type of tool might be called  cardwareoptic cable and the quality of the signal mustby analogy with hardware and software.One ofgather optical (rather than electrical) data.the most effective tools for accomplishing any-Consequently, special equipment is needed.thing is an ability to get the resources or informa-Ironically, this equipment gets its informa-tion needed for a particular task.tion from electrical signals.These signals areForms, checklists, or question collections can becreated by converting the optical signal toinvaluable for getting information.Committingelectrical form.items or questions to paper makes it easier toAn optical power meter is the analog toexamine the entire collection to determinethe VOM mentioned earlier.This device canwhether it gets all the necessary informationdetermine the power of a signal in decibelsor points.(dB) or in decibels referenced to a milliwatt(dBm).The latter provides a standardizedBy doing this in advance preferably testing, eval-way of specifying signal strength.uating, and revising it as necessary you can pro-An Optical Time-Domain Reflectometervide a reference against which to compare(OTDR) serves as the foundation for higher-competing options or products.end cable testers.The optical time domainSuch forms and questionnaires are found in maga-reflectometry that underlies this device useszines, technical and marketing brochures, andthe light scattered back from a signal (oreven advertisements.You can sometimes putlight bounced back for a test signal) andtogether a useful checklist of desirable features byallows sophisticated measurements oncollecting comparisons from the manufacturersthe light.of each of the products.These devices cost several thousand dol-lars but can provide valuable information,such as signal loss per unit distance and Like the closely related MAP (Manufac-signal loss at splices or over connectors.turing Automation Protocol), TOP is aneffort to provide standardized protocols andservices for use in real-world contexts thatTOP (Technical Office Protocol)involve the reliable and efficient exchange ofTOP is an architecture that provides stan-formatted data or access to such data fromdards for the representation and exchangeremote locations.of messages, documents, and other files inTOP APIsoffice settings [ Pobierz całość w formacie PDF ]

  • zanotowane.pl
  • doc.pisz.pl
  • pdf.pisz.pl
  • funlifepok.htw.pl

    •