Table of ContentsContentsDesignAir-blown fiber turns the wheels at AAMA glowing red slab of steel moves into the giant press. The operator activates the press and, seconds later, a gear-shaped blank emerges, still red-hot and smoking. Two blocks away, in another building of this 18-city-block complex, robots insert red-hot axle shafts into induction hardening machines. Amid this intense, 24-hour-a-day, seven-day-a-week production routine, two installers are preparing to run optical-fiber data-communications cable to expand the plant`s local area network (LAN).
The Getty Center project scorecardThe Getty Center project (see "Largest private U.S. building project cabled with air-blown fiber," August 1997, page 25) has provided a great test bed for air-blown fiber (abf) technology as well as for fiber-to-the-desk. The installation at the Getty Center (Los Angeles, CA) is where aidco Inc., an installation company based in Chino, CA, demonstrated its high level of expertise and experience in designing and installing abf systems.
Comparing component requirementsThe components used for an air-blown fiber (abf) system compare favorably to standard fiber equipment. In terms of the physical-space requirements and overall costs, high-density fiber-optic crossconnect units and mechanical splice enclosures used in abf installations typically compare well to standard fiber termination and distribution units that require connectorization of the fiber.
Making the optical connectionDuring the last decade, premises cabling has evolved greatly, and part of that change has been an increase in the use of optical-fiber cabling media. Going hand-in-hand with this increase in fiber use has been the development of optical components that support fiber-optic cabling installed in high-speed local area networks (lans).
InstallationCommissioning a fiber-optic LANCommissioning a fiber-optic local area network (LAN) involves a series of steps that are taken to prove that the system meets the specified requirements. The requirements can be a series of specifications from the manufacturer of the system, the owner of the installation, or a third party such as a government agency.
OTDRs add features, improve performanceOptical time-domain reflectometers (OTDRs) are finding ever-increasing use in premises and campus networks as optical fiber has become the medium of choice for backbone applications and gradually makes its way to the desktop for high-performance tasks.
Installation considerations for fiber-optic cableInstalling optical fiber in horizontal cable runs is simple and, in many cases, much easier than installing unshielded twisted-pair cable. The most important factor in such installations is maintaining the cable`s minimum bend radius. Bending the cable more tightly than recommended may result in increased attenuation or broken fibers.
Product UpdateCable-hanging hardware supports horizontal cabling runsRouting cable throughout a telecommunications network is a constant battle against the law of gravity. While nature pulls the cable downward, cable installers and cable-plant managers are tasked with keeping the cable supported so that it does not sag. This requirement is especially critical, although frequently ignored, above suspended ceilings. Good professional practice dictates that cables not be allowed to rest on ceiling tiles because the tiles can be damaged and, more important from a net
TechnologyIndoor/outdoor cable turns the cornerThis versatile fiber-optic cable makes the transition between outside- and inside-plant environments.
Crosstalk & FeedbackAsk DonnaCabling-hanging and the NECQ: At the recent Cabling Installation Expo `97 in Charlotte, NC, a letter was distributed by one of the vendors stating that according to the National Electrical Code (NEC) and the revised tia/eia-569a, it is permissible to attach appropriate cable fasteners on suspended ceiling support rods or wires that may carry multiple cables. They state in the letter, "But what happens if the local inspector will not permit it? Here are the facts: Nearly all local codes are based on the nec. There is a pro
Wrapping fiber cable around overhead lineQ: I am looking for a machine that would wrap fiber-optic cable around an existing overhead cable line. The idea would be to use the existing line and poles to add a transmission network over the line of a power company. This machine would ride the existing cable and wrap fiber-optic cable around it. Do you know of a company that provides such a device?
Is a star pass satisfactory?Q: When testing a Category 5 cable run we read a star pass on the remote near-end crosstalk. The margin was 1.7. Is this acceptable? The cable manufacturer said that even if the margin were 0, the test would be satisfactory.
Innerduct for fiber?Q: Should fiber-optic horizontal cable be installed in innerduct? In the environment in question, plenum fiber-optic cable is being installed between a data closet and a classroom. As you know, educational facilities want quality jobs but are mindful of the costs.
Upgrading to Category 5Q: My company is getting ready to move upstairs. The space we are moving into is already cabled with a Category 3 system throughout. The installers coming in to cable have suggested to our facilities manager that we do not need Category 5. Our server has a 10/100 card and our switch is upgradable to 10/100. We run 10Base-T. I have always used Category 5 and believe that, for performance issues, it is needed. However, this is a big added cost to our move. Should we have all Category 3 pulled and
Between the linesTrue, the National Electrical Code (NEC), Article 90-3 "Code Arrangement," states that "Chapter 8 covers communications systems and is independent of the other chapters except where they are specifically referenced therein." But what about the optical fiber in Article 770 and the Class 1, Class 2, and Class 3 remote-control, signaling, and power-limited circuits in Article 725? Yes, they must meet guidelines specified in Chapter 3, "Wiring Methods and Materials", Section 300-11, which specifical
EditorialA new year...and a new lookOne of the hardest things a magazine editor has to decide is what works and what doesn`t. We at Cabling Installation & Maintenance have been happy, overall, with the magazine`s reception by and reputation with its readers, so the thought of changing what works is one we have put aside whenever it has come up.
EndfacePropagation delay and delay skew remain important issuesIn September 1997, the first addendum to tia/eia-568a, the revised commercial building cabling standard, was released. tia/eia-568a-1, "Propagation Delay and Delay Skew Specifications for 100-ohm, 4-pair Cable," establishes additional performance requirements for unshielded twisted-pair (utp) and screened twisted-pair cables that are critical for applications that use multiple pairs in a cable for parallel transmission. The Telecommunications Industry Association (tia--Arlington, VA) continues t
Products & ServicesIndustry SpotlightFCC chair announces plan to end regulated telecommunicationsAccording to a report by Communications Daily, new Federal Communications Commission (fcc--Washington, DC) chairman William Kennard announced that his office will forgo a new partnership with state regulators. The report said that Kennard wants to develop a plan, which he called a "Magna Carta for competition," to end regulated telecommunications.
CSI/Suttle and Mohawk/cdt announce performance partnershipSpurred by rapidly evolving technology needs, Communications Systems Inc. (CSI/Suttle--Hector, MN), and Mohawk/CDT (Leominster, MA) announced their partnership to create enhanced local-area, wide-area, and metropolitan-area network systems.
Prestolite purchases Northern Lights CablePrestolite Wire Corp. (Southfield, MI) plunged into the fiber-cable market by acquiring Northern Lights Cable (North Bennington, VT). Northern Lights manufactures fiber-optic cable and telecommunications-industry assemblies. With the addition of Northern Lights, Prestolite`s product offerings now include fiber-optic cable, and copper-wire products, including unshielded twisted-pair cable, for voice and data communications.
Moves, Adds & ChangesTelecommunications Techniques Corp. (TTC--Germantown, MD), a manufacturer of test products, systems and support services, named Gary Maverick president of the newly formed Systems and Software Div. He has more than 20 years of experience in product development and management. Before joining ttc, Maverick served as general manager/chief operating officer of Sodalia S.p.A. in Italy, a joint venture between Bell Atlantic and Telecom Italia.
New ProductsDigital multimeterThe LT83 digital multimeter has four millivolt ranges (200 mV AC and DC, and 2000 mV AC and DC) and measuring ranges in volts (to 600V), AC or DC, amps and microamps (to 10 amps), and resistance (to 20 milliohms). For low-current measurements, the unit has 200 microamps AC and DC, with resolution down to 0.1 microamp. Priced at $44.95, the device provides a 2.5 times/sec nominal measurement rate. Other features include data hold, max hold, a continuity resolution beeper, and an lcd low-battery i
Patch panel kitThe TracJack 24-port patch panel kit allows duplication of port configurations in the wiring closet to correspond with the workstation. The panel`s rear shelf provides cable management and fiber storage for standards compliance. The patch panel accommodates a wide selection of front-loaded and front-removable enhanced 110 Category 5 multimedia snap-in TracJack modules. Each panel is 19 inches wide and two rack units high.
Cable cabinet systemThe MegaFrame cabinet system combines rack components, storage, security, and protection with full cable and cord management in a closed environment. The system has built-in cable management, which provides 3-inch clearance from the cabinet sides, and adjustable cable rings. MegaFrame can be used as either a standard four-post cabinet or as a 2-channel rack by sliding the mounting rails together. The units are shipped either fully assembled or unassembled.
Test equipment and tool catalogA 268-page catalog covers hundreds of new test instruments and tools for telecommunications specialists, engineers, installers, and technicians. The catalog features brand-name products for testing, repairing, and installing telecommunications and data-communications equipment. New product highlights include Microtest`s MicroScanner utp cable tester and Category 5 cable testers. All products are fully guaranteed, and same-day shipping is available.
Category 5 110 wiring productsA line of Category 5 110 wiring blocks includes field termination kits and comes in 100- and 300-pair sizes, with or without legs. The kits contain connecting blocks, patch cords, cable-management system, labeling, and tools. Patch cords come in 110-to-110- and 110-to-8-position versions. The plug features a crosstalk elimination technique that improves near-end crosstalk performance. All cords are yellow and are available in 3-, 5-, 7-, 9-, and 12-foot lengths. The connecting blocks terminate 2
Cordless drillsThe JobSite series of cordless drills and drivers includes center-handled 14.4V and 12V 3/8-inch and 18V 1/2-inch versions. The drills have industrial keyless chuck, 24-position adjustable clutch, and an electric brake. A two-speed gear box provides variable speed ranges of 0 to 350 rpm and 0 to 1300 rpm for the 18V (cth1802K) and 14.4V (cth1442K2) models, and 0 to 300 rpm and 0 to 1000 rpm for the 12V model (cth1202K2). Two screwdriver bits, carrying case, two battery packs, and a 1-hour diagno
Cable rackThe DC-8035 open rack assembly consists of the arr-1272-bt black-finish aluminum rack, 12 cableway rings, one pair of cableway covers, six cable rings, and all assembly hardware. The rack provides 19 x 77 inches of usable panel space. It can also be used with all of the company`s open rack accessories.
Electronics catalogA 300-page catalog contains items for the electronics and related industries. Two new kits featured in the catalog are the jtk-2001 PC Workstation Plus and the jtk-2900 network support kit. New test instruments, specialty tools, testers, and probes are also included in the catalog. An eight-page section covers Hewlett-Packard devices, such as oscilloscopes, logic analyzers, function generators, and universal counters.
Fiber polishing machineThe Model fpol one-step automated fiber polishing machine simultaneously polishes two fiber connectors in 15 seconds. Weighing 1 pound, the unit accomplishes more than 250 terminations on a standard 9-volt alkaline battery. The device comes with a universal connector holder that accommodates ST, SC, and FC connectors. The fiber polishing machine features water-free operation, which eliminates messy cleanup.
Trade association factbooksWhen you are planning next year`s budget or writing up a new business plan, it is often useful to have overall industry statistics to back up your points and projections. One source of such statistics is the reports of market research firms covering your industry, but such reports tend to be very expensive. A less costly source of overall industry statistics and information can be found in the factbooks sometimes published by trade associations.
Premier ProductsGigabit-ready copper cabling systemsNORDX/CDT has introduced two structured systems that can handle gigabit transmission. The ibdn Gigabit Cabling Solution System 1200 and System 2400 include cable and connecting hardware manufactured by NORDX/CDT. The System 1200 is built using PS5 connectivity hardware--which includes patch panels and workstation outlets--and the company`s ibdn 1200 series unshielded twisted-pair (UTP) cable. According to the manufacturer, the 1200 system delivers a higher signal-to-noise ratio than do conventi
Category 6 LAN testerDatacom Technologies now offers test equipment that it guarantees will test unshielded twisted-pair (UTP) cabling for Category 6 performance.
Patch cord adjusterThe PerfectPatch patch cord adjuster with KinkGuard eliminates patch cord entanglements and slack. The adjuster reduces patch cord length up to 60%, and its bend radius stability protects cables from kinks. Manufactured in 1-foot-incremental lengths of 3 to 10 feet, the device adjusts to many different diameters and works on most patch cords and all wire management systems, but each cable`s diameter should not exceed 1/4 inch. To create different colored patch cords, apply color stickers or icon
Cable Installer TipsUse caps from cable boxes as grommets during cable distributionWhen you route cables through a steel-stud top plate, the cables can easily snag or tear against the sharp edges of the hole drilled into the plate.
Removing multipair cable from old conduitOld 25- or 50-pair cable often sticks tightly to the inside of old conduit and cannot be removed by pulling. For this reason, many users abandon the use of the conduit.
Avoid excessive untwisting of pairs in Category 5 cableWhen terminating Category 5 cable to a 110 block, installers often leave more than 1/2 inch of each wire pair untwisted. This practice is in conflict with installation recommendations included in the tia/eia-568a commercial building wiring standard.
Transitioning cables to modular workstationsTransitioning communications cabling into modular furniture from a wall or column is often difficult because hole plates designed for this procedure are rare.
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January 1998
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