Table of ContentsContentsDesignGrounding and bonding ensure a safe installationIt may seem difficult to think in terms of voltage surges instead of current surges. In fact, current from lightning or another high-energy event would probably vaporize most data lines. Transient voltages (ground potential rise), which appear throughout the ground path itself, cause more damaged equipment, lockups and garbled data than any other phenomenon. Current flowing in power circuits, grounds from in-rush, short circuits and lightning cause transient voltages. Understanding that groundin
InstallationInstalling and testing fiber-optic cabling plantAlthough fiber-optic networks differ significantly from copper-based networks, the methods for testing and troubleshooting them are very similar. The techniques can easily be mastered by technicians with some basic training in fiber optics and network testing. The procedures discussed here have been thoroughly field-proven in thousands of installations, and they will help installers locate problems in time and at the source.
Product UpdateMultimedia outlets fit many applicationsMultimedia outlets support different types of cabling--coaxial, fiber, unshielded twisted-pair and shielded twisted-pair. With a snap in or out, you can configure and modify outlets to meet the needs of your installation. Choose from a variety of connector options and, when you need to change or upgrade, remove the existing modules from the wallplate and replace them.
StandardsFCC rules on premises wiringAlthough the Federal Communications Commission (Washington, DC) has deregulated premises wiring from the exchange carriers, the government organization still maintains certain wiring and component requirements. These requirements are set forth in Part 68 of the FCC`s Rules and Regulations.
Comparison of International and Domestic CablingThe 11801 standard of the International Organization for Standardization (ISO--Geneva, Switzerland) and the International Electrotechnical Commission (Geneva, Switzerland) covers generic cabling for customer premises and will soon be published as an international standard. The 568 telecommunications cabling standard for commercial buildings, issued by the American National Standards Institute (New York, NY), the Telecommunications Industry Association (Arlington, VA) and the Electronic Industri
TechnologyFiber-optic component makers address price barriersThe fiber-optic industry is much like a 15-year-old teenager who is rapidly growing, prone to change and still immature. While applications for fiber continue to emerge--for example, in local area, wide area and metropolitan area networks--and fiber is driven deeper into the public network, there is a need for new fiber-optic components. To meet market needs, installers of fiber-optic systems are calling for less-expensive and more-advanced products, and manufacturers are devising processes to
Crosstalk & FeedbackAsk DonnaCategory 3 versus category 5Q: I have been assigned to find out if we should be installing Category 5 unshielded twisted-pair cable in our buildings as we modernize. Currently, we have a wiring plan that specifies two Category 3 four-pair, UTP cables to each workstation. We have been asked to run at least one Category 5 and one Category 3 cable to each workstation. Is the current philosophy to install Category 5 now just in case there will be a requirement later? And isn`t the price of a Category 5 cable plant increased by
Collapsed backboneQ: For the past year, I have been designing a new three-story building at a national laboratory. In the beginning, I had to fight with the architects for space on each floor for a telecommunications closet. When I finally received a set of blueprints--and all the space I had fought for--I proceeded to lay out the horizontal and riser cabling scheme. Three-quarters of the way through this phase of the project, my supervisor insisted that home runs go to the first floor, where the main crossconne
EditorialThe latest newsAs editors of Cabling Installation & Maintenance, we receive dozens of press releases and product announcements daily. We also sift through trade magazines, conference proceedings and other publications looking for stories that we think you will be interested in. (These activities, of course, are in addition to going to meetings and shows, visiting installers and suppliers, and spending a lot of time on the phone.)
Shielded and unshielded twisted-pair cable revisitedRecently, the advantages and disadvantages of shielded and unshielded twisted-pair cable have been under debate. Advocates of STP cable, which includes screened twisted-pair and foil twisted-pair cables, claim that it is superior to UTP cable. However, these advocates have not presented the other side of the story.
Products & ServicesIndustry SpotlightHow the new OSHA asbestos regulation affects installers[Editor?s note: This is a synopsis of the OSHA regulation and is not intended as a substitute for a thorough reading of the rules published in the Federal Register as 29 CFR, Parts 1910, 1915 and 1926.]
Connecticut Telecommunications Industry Association is bornAt a meeting in June, The Connecticut Telecommunications Industry Association was formed as a trade group for installers in the State of Connecticut. Terry Buono, president at Cable Systems of North Haven Inc., is interim president of the association until elections can be held later this year--probably in October.
Moves, adds and changesFor its 25th anniversary and to reflect its focus on connectivity, Vertex (Farmingdale, NY) is changing its name to Vertex Technologies Inc. In addition to its role as a distributor and manufacturer of products and services for the data and voice communications industry, the company now provides systems integration services and technical support.
New ProductsFiber-optic power meterThe 7700C high-power fiber-optic power meter measures the absolute or relative power of light from a fiber-optic cable. Serving cable-TV and other applications where it is necessary to measure the output power of high-power sources, the power meter offers two-button operation, large LCD display and a universal connector interface that allows the user to test terminated or unterminated fiber-optic cables.
Category 5 patch cableQuicklink preterminated, 100-meter coil of Category 5 patch cable is available in PVC or plenum. Intended to be used to jump-start a link by patching directly from the workstation to the patch panel, the coil is suitable for bypassing a cabling problem in an existing plant, for disaster recovery or for adding additional workstations. The cable is terminated with RJ-45 jacks wired for 568A or 568B with snagless strain reliefs on each end.
Handheld TDRModel 87 time-division reflectometer locates bridged taps and faults and measures lengths to within one foot on installed cables. The TDR also measures up to 1500 feet of cable on a reel. This handheld device locates open, shorted and good cable pairs from one end of the cable, without the use of a remote adapter. Two built-in RJ-45 jacks and a BNC connector are included for testing systems.
Modular tower systemThe S110 modular tower system is a high-density field-terminated, crossconnect and cable-management system. This wall-mounted system features fanning slots and 1/4-turn fasteners for installation and removal of S110 wiring blocks. The system enables vertical stackability and horizontal expansion. A field terminated kit is also available.
Stainless-steel cable tiesKynar-coated cable ties secure bundles of NEC-qualified in-plenum cables in such applications as remote control, signaling circuits, communications circuits, cable-TV systems, optical-fiber cables and fire-protection signaling systems. Made from stainless steel, the ties can be used -29 to +140C. They offer a flammability rating of UL 94V-0.
Test instrumentationHandheld fiber-optic test instruments feature a universal adapter system and removable silicone housing. Test instruments include single- and dual-wavelength LED sources, laser sources, optical power meters, variable attenuators, fault locators and fiber tracers.
Raceway systemSeries 4000 two-piece surface metal raceway perimeter wiring system delivers cable to key locations in a building. The system can be installed at the baseboard or at desk height. Series 4049 plastic device plates overlap adjacent covers that hide seams ordinarily found between plate and cover.
Deep-drawn enclosure catalogThis 60-page catalog details more than 75,000 pre-tooled sizes of deep-drawn aluminum enclosures. Listed in table format are options for covers and standard nutplate/junction box assemblies. Precision miniatures in aluminum, brass, copper, metal and steel are also described.
Two-port surface boxThe two-port surface box consists of a base and cover. The base accepts two jacks or connectors that snap into place. For each port, the box includes built-in strain relief that locks the cable into place and simultaneously feeds the cable directly into the jack or connector. The box can be mounted using two screws or Velcro strips.
Fiber organizerNetwork Splice Organizer protects splices in low-fiber-count applications. Used for customer premises wiring closets and equipment rooms, this compact wall-mountable unit projects less than 2 inches from a wall. Bend radius and cable strain-relief ensure optical fibers are protected. The organizer houses singlemode and multimode fibers.
Heat-shrinkable markersHeat-shrinkable wire markers are offered in several material grades, depending upon the desired rigidity, flexibility, shrink ratios and flame retardancy. They are custom hot-stamped and sequentially numbered and can be coiled and cut to length for storage and tear-off use. The markers are available in single- and dual-wall (adhesive-lined) configurations.
Communications products catalogThis 320-page communications products catalog contains photographs, technical drawings and specifications for copper, fiber-optic and test equipment products. Features, advantages and benefits of each product are described. A product referral guide is included.
Silicone tapeTYT200 self-fusing silicone tape, developed as a replacement for heat-shrinkable tape, is an all-purpose tape suitable for high temperatures and harsh environments. The 1-inch wide tape, available on 14- or 36-foot rolls, is for wire, cable and connector identification.
Power metersSeries OPM 5 optical power meters suit singlemode and multimode applications. During installations, the power meters store 250-loss readings in nonvolatile memory for future downloading to a printer or computer. When linked to a computer, the power meter becomes a diagnostic lab meter with DOS-based software that offers real-time measurements on the computer screen and time-based measurements for stability testing.
Fiber-optic cabling plant softwareFodoc software, a database that runs on PCs, tracks every component in a fiber-optic network, including fibers, slices and connections. The software can be used for designing the cable plant, bidding jobs, installing cables, and testing and archiving data on the cables. Estimating and troubleshooting reports are generated.
Fixed attenuatorsSeries 944 FC and 954 SC plug-style fixed attenuators feature dual-wavelength performance at 1310 and 1550 nm and are available in attenuation values of 5, 10, 15 and 20 dB with plus or minus10% attenuation tolerance. Backreflection performance is -48 dB typical and -45 dB maximum. The attenuators fit into existing patch panels equipped with FC or SC feed-through adapters.
Bare-fiber adapterThe Bullet bare-fiber adapter temporarily places industry-standard connectors on unterminated fiber. The adapter enables repeated connections and consists of machined aluminum with stainless-steel connector modules.
Optical multimeterModel AQ 2140 optical multimeter functions as an optical power meter, stabilized light source, loss-test set or return-loss measurement system, depending on the configuration. The multimeter`s sensor units offer plus or minus 2.5% accuracy and cover wavelengths from 700 to 1870 nm. The device can also graph data and plot directly to a plotter.
Cable-testing toolThe Dual Remote 100 is used with the Wirescope 100 cable analyzer to measure near-end crosstalk and attenuation to crosstalk at both ends of a cable link, without having to switch locations. This feature eliminates the need to perform two tests on each cable. The device qualifies Category 5 cable links to 100 MHz, according to company claims.
SC-style connectorThe Lightcrimp SC fiber-optic connector provides epoxyless termination of optical fibers for premises wiring and network applications. The connector incorporates technology that mechanically clamps multimode fibers in place without the use of epoxy, ovens or ultraviolet curing. Insertion loss is 0.3 dB.
Voice, data and fiber-optic cable bookletThis 98-page booklet covers more than 2000 items, including 70 types of wires, cables and cords. The publication describes connectors, tools, jacks, panels and tubing. Also featured are alarm, audio, coaxial, control, data, fiber-optic, IBM-compatible, LAN, telephone, TV and cable-TV cables.
Cabinets/enclosures catalogData communications and telecommunuactions cabinet racks, relay racks and accessories are detailed in this 15-page catalog. Products include the data communications cabinet assembly, the economizer cabinet rack, aluminum and steel relay racks, wall-mounted communications cabinets and fiber-optic enclosures.
Polishing filmThis lapping film polishes fiber-optic connector endfaces. Available in aluminum oxide, silicon carbide and diamond, the film comes in popular sheet sizes, as well as round disks. Stock particle sizes range from 0.3 to 30 microns. Pressure-sensitive backing is optional.
Cable Installer TipsWiring a Category 5 66 blockWiring a 66 block with Category 5 unshielded twisted-pair cable requires a different termination method not typically used with voice-grade cables.
Corrugated tubing can protect work-area cablingPower poles often connect directly to modular furniture, permitting cable to run from ceiling to raceway without being exposed. However, when cable must exit a structural pillar or wall, it may be exposed for a short distance before entering the modular-furniture raceway. The exposed cable bundle crossing this gap is unsightly. It may also represent a hazard; people walking by may trip on it, hurting themselves and potentially damaging or disconnecting the delicate cables.
Solving Category 5 near-end crosstalk problemsSometimes when testing Category 5 cabling, you may have a problem with a cable termination that fails near-end crosstalk on pairs 4,5 and 3,6, while pairs 1,2 and 7,8 pass. Pairs 4,5 and 3,6 are the toughest pairs to pass near-end crosstalk because they are the two center pairs on the RJ-45 jack. Pairs 1,2 and 7,8 on the outside of the jack are less susceptible to near-end crosstalk problems.
Testing for data linesAs the number of digital data lines increases, it becomes more important to test for them. If a technician, however, attaches a piece of test equipment to a data line, mistaking it for a standard voice line, the result is a spike or glitch on the data line. This cord makes the data unusable and dumps the entire transmission.
Clean and test hybrid jumpers before useHybrid jumpers are used to connect an optical-loss test set to an optical fiber terminated with connectors different from those resident on the test set--for example, SC-to-ST. Ideally, jumpers should not affect test results, but if they are defective or if their connectors are scratched or contaminated, they may make the loss measurement performed on the fiber link inaccurate.
Measuring cable length using nominal velocity of propagationLength is one of the four primary test parameters specified in the American National Standards Institute/Telecommunications Industry Association/Electronic Industries Association PN-3287 draft standard and should be recorded as part of any copper-cable administration system. Handheld testers rely on the nominal velocity of propagation of the cable type to determine length measurements. Each type of cable insulating material--polyvinyl chloride, fluorinated ethylene propylene or polyethylene--has
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This IssueNo Image Available Volume 3
Issue 9
September 1995
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