Table of ContentsContentsDesignDesigning telecommunications for small offices and home officesAs we prepare to enter the twenty-first century, our residential and light-commercial cabling must be brought up to par with the sophisticated electronic and telecommunications equipment we acquire for business and entertainment.
Enhanced-performance Category 5--A look at usable bandwidthThe enhanced-performance cables now being offered by some manufacturers call for understanding many more electrical properties than has been the case with lower-grade cable.
Point of View: Little vertical in horizontal fiber trendsGreat enhancements have been made over recent years in the handling and routing of fiber-optic cables and the connectors that tie these cables to destination points. Fiber advocates say it is the most universal medium--capable of carrying voice, data, and video communications simultaneously with less signal enhancement than that required with copper cable. Furthermore, fiber enthusiasts point out that fiber is sufficiently robust to withstand the bends and stresses prevalent in the horizontal po
Office design for knowledge workersCompetitive pressures and the changing nature of work mandate more-flexible office and telecommunications-systems design.
InstallationDigital calls on multipair cable for voice and data networkThe computer hardware manufacturer specified bundled Category 3 and Category 5 cable for its customer-service center.
Product UpdateCable strippers perform basic but important functionsThe most basic of the tools in a cabling installer`s kit, the cable stripper, can easily be taken for granted. Installers use so many other more-expensive, highly technical tools and testers in an installation that the cable stripper may not get a second thought.
StandardsPatch cords--the missing link in cabling standardsInstalling a cabling system is a little like baking a cake, according to John A. Siemon, vice president of engineering at The Siemon Co. (Watertown, CT). "With a recipe," he said at a panel discussion on unshielded twisted-pair (utp) patch cords that he moderated for bicsi (Tampa, FL) this year, "if you know the ingredients and what to do with them, you should have a fairly good idea of how the result will turn out."
Standards group prepares for gigabit traffic on Category 5 cablesWorking Group TR-41.8.1 within the Telecommunications Industry Association (tia--Arlington, VA) is working to categorize the transmission performance of Category 5 cabling for Gigabit Ethernet applications. The group`s goal is to complete the specifications for a minimally compliant Category 5 channel. Most of the installed base of Category 5 cabling will likely meet this specification, which will include requirements for worst-case channel return loss, multidistributor near-end crosstalk, and f
TechnologyAdapters bridge the gap between fiber-optic connectorsFiber-optic adapters form a small, but critical, part of the hardware used in an optical-fiber cabling system. While the importance of adapters is often overshadowed by connectors, product manufacturers continue to stress the significant role that these devices play in overall interconnection performance.
Crosstalk & FeedbackAsk DonnaCombating electromagnetic interferenceQ: We have a number of new communications (voice and data) cable installations and are constantly addressing problems with electricians installing cable and electrical devices adjacent to communications cable runs, causing electromagnetic interference (emi). I am in search of an industry-standard specification stating distances from cable to emi-causing devices. The electrician`s bible, the National Electrical Code (nec), only mentions a 2-inch clearance between power and communications cables.
Cable-management softwareA: Truthfully, we all do. The 1997 Cabling Installation & Maintenance Buyer`s Guide Issue has a section on cable-management software (see page 218). Check it out on the World Wide Web at www.lfw.com/www/cim/bg/pcimm130.htm#Top. This will allow you to browse and contact vendors for specific product information.
Token Ring LANsQ: Do you know of a good reference for determining cabling distances using Category 5 cable for Token Ring? I need to determine the lengths possible when multiple closets are involved. Also, what is the best way to handle shielded and unshielded twisted-pair (stp/utp) lobes on the same Token Ring local area network (LAN)?
Multimode fiber for cable TVA: Bandwidth is the measure of the information-carrying capacity of an optical fiber. The information-carrying capacity of a transmission medium is normally referred to in units of MHzkm. Called the bandwidth-distance product, this value is the product of the length of a fiber (in kilometers) and the bandwidth that the fiber can transmit over that length (in megahertz). The amount of information that can be transmitted over any medium changes with distance, and the relationship is not necessaril
EditorialCutting-edge memorabiliaNot too many years ago, as I was entering the world of adolescence, I often envied my next-door neighbor. Eddie was the first kid in the neighborhood to have everything. He bought record albums on the day they were released, was at the front of the line to see Star Wars the first day it was in theaters, and had a video-game collection to die for.
Is the cabling industry leveling with end-users?Extended-performance, high-performance, Level 5, Level 6, Level 7, Cat- egory 6, high attenuation-to-crosstalk ratio, 350-megahertz, 600-MHz--these are all terms currently being bandied about to describe the new world of high-speed cabling systems. Are these terms being used to bring enlightenment to the end-user or customer, or are they being used to further confuse the already confused?
To The EditorBusiness partnerships and standardsI recently read and wanted to reply to your editorial in the June 1997 issue (page 5), "Are business partnerships counter to standards?"
Another mystery to lose sleep overHere`s another mystery to ponder: Why did the Gigabit Ethernet Committee vote to approve 50/125-micron optical fiber? Can you imagine the disastrous effect this decision will have on end-users? They`ll say, "Now we`ve got another fiber to consider, so obviously fiber has no standards at all!"
Products & ServicesIndustry SpotlightAnixters Levels program to include connectivityAnixter Inc. (Skokie, IL), a provider of integrated communications systems and services, has announced that its Levels `97 program will include connectivity and modular cable assemblies, in addition to twisted-pair cable.
Berk-Tek develops enhanced Category 5 cableCabling-product manufacturer Berk-Tek (New Holland, PA) has developed an enhanced Category 5 unshielded twisted-pair product--the lanmark-1000 cable series. Available through the company`s distributor/representative network, the lanmark-1000 uses full-duplex operation over all four twisted pairs.
Fluke offers free upgrade on cable-test toolFluke Corp. (Everett, WA), a supplier of products and services for the installation, maintenance, and troubleshooting of computer networks, now offers a free upgrade to version 5.0 of its dsp-100 CableMeter test tool. The upgrade lets cable installers perform test measurements, including power-sum near-end crosstalk and headroom, based on worst-case near-end crosstalk margin over the total bandwidth tested.
Moves, Adds & ChangesMark Greenwell has been appointed vice president of sales and marketing at Datacom Technologies (Everett, WA), a provider of network management and test products. He heads Datacom`s global sales, marketing, and customer support operations. Greenwell has more than 15 years` experience in the networking and computer industries and has served as U.S. sales manager for Fluke and director of North American sales for Microtest.
New ProductsCable cutterThe battery-powered cable cutter cuts 750-mcm hard-drawn cables or 1000-mcm copper and aluminum cables. Its 12V rechargeable battery is rated for 1000 charges. This compact cutter has hardened steel blades, abs 770 housing, and a three-way switch lever. The device comes in various component options, including a kit that contains all essential elements in one carrying case. With attached wrist loop, the cutter is suitable for use in tight, overhead areas.
Self-laminating markersConstructed of translucent vinyl film, JetTab B-117 cable markers suit electrical and telecommunications applications. The labels can be used with inkjet printers, so large quantities can be printed without sacrificing legibility or durability. A clear laminating film wraps around the cable and over the print area to protect the label from fading, moisture, and abrasion. The cable markers come in eight sizes and are available in polyester, paper, polyolefin, repositioned cloth tape, and Permashi
Cable trayThe SpecMate center-spine cable tray uses single hangers attached to the center spine rather than a conventional trapeze hanger, so only half the number of hangers is needed, and installation time is reduced. The screw-in rungs have integral grooves for mounting of screw-in accessories (e.g., cable dropouts), and the rungs are easily removed to facilitate installation in tight locations. Wire and cable can be laid in from the side, so cable pulling is eliminated in many installations.
Network jacksSnap-in module interfaces for the TracJack single-jack network solution include enhanced RJ-45, 110 Category 5 RJ-45, RJ-25C, F connector, dual rca, ST, duplex ST, SC, duplex SC, FC, and blanks for future expansion. The modules are ansi/tia/eia-568a-compliant and meet all fcc Part 68 specifications. The jacks are also available with single- and dual-gang faceplates, low-profile surface mount boxes, and 19-inch patch panels.
Telecommunications cabinetsThe etrak telecommunications enclosures are compatible with 450- and 500-millimeter-wide equipment as well as 19-inch equipment when used with adapters. Other features include separation of copper, fiber, main, and earth cables; accessories for placing racks back-to-back and side-to-side; and built-in cable tie slots. The cabinets come in several different styles, including an emc version, and in depths of 300 to 600 mm. Price starts at $930.
Computer space management systemAn open-architecture system for computer equipment is vertically organized to increase storage capacity, simplify cable management, and facilitate system expansion. Components include lan racks, raid racks, server support modules, stackable wall-mounted racks, standard and universal racks, earthquake-bracing kits, and various heavy-duty shelves that can support up to 200 pounds. Shelf and tray fabrication range from cold-rolled steel to lightweight aluminum in 19- to 25-inch widths.
Polyethylene racewayThe Optic-Gard PE raceway system provides a permanent pathway for future installations, replacements, or upgrades. The device is available in direct-buried and innerduct-rated raceways. Packaged on returnable steel stock reels and stock coils, this polyethylene raceway system comes in various colors, configurations, and sizes, and with preinstalled ropes or tapes.
UPS systemThe SmartPro network uninterruptible power supply (ups) systems include ups power, PowerAlert Plus power-monitoring software, and cabling in a single box. The rack-mounted units (SmartPro 2200 RM, 2200 rmxl, and 3000 RM) feature three lan ports for simultaneous multiple server support and control, even when servers are running different operating systems. The units feature eight AC outlets (six on Smart 700 RM) and can be used in standard 19-inch racks.
Coaxial connectorsThe MicroMate surface-mount coaxial interconnectors guarantee mechanical and electrical performance to 6 gigahertz. These 50-ohm smd connectors feature the mmcx interface that complies with the European cecc22000 specification. Other features include lower profile and guided entry to eliminate misalignment, vertical-only mounting to eliminate crosstalk, additional mounting pad for added strength, and semirigid and flexible cable options.
Wire and cable markersThe Wrap-Up wire and cable markers provide fast and permanent field identification. Available in widths from 1.5 to 6 inches, the markers fit virtually any size cable or wire and come in eight colors to meet tia/eia-606 standards. The technician can use a marking pen, ball-point pen, or typewriter; markers for laser printers are also available. A clear laminate permanently protects against dirt, oil, and water.
Cable locator carrying caseThe TW-770 pipe and cable locator is now available with a soft padded carrying case as well as the original hard-shell case. The soft-sided case is significantly smaller than the hard case, but still has enough extra space to hold the TW-770 ground rod/ground plate assembly, coupling clamp, headphones, and other accessories. The price of the soft and hard-shell case is the same.
Coaxial cableThe 5/8-inch ldf4.5-50 Heliax cable for wireless applications is also appropriate for long cable runs where low-attenuation is required. This coaxial cable features low-loss foam dielectric, solid-center conductor to facilitate connector attachment, and solid copper corrugated exterior for shielding. A full range of connectors and accessories are available, including din and Type-N connectors, hangers, grounding kits, and adapters.
Fiber interconnect productsConstructed of steel with a black, baked epoxy powder finish, Light Express 2 interconnect products come equipped with cable management reels. Each product is preloaded with industry-standard fiber-optic adapters. ST and SC cable assemblies manufactured with industry-standard ST and SC connectors are also available. Each connector is fitted with a zirconia ceramic ferrule for optimal performance.
Battery racks and traysA new tray for the Phoenix-series valve-regulated batteries is constructed of 14-gauge steel that has been coated with acid-resistant ansi gray #61 paint. The tray holds four Phoenix batteries, supports 420 pounds, and mounts to a standard 23-inch relay rack. Inside tray dimensions are 21 x 21.85 inches. The cabinets are rated for Zone 0 and house up to 48 batteries, depending on the size. Relay racks start at $120 each; battery cabinets at $1410 each.
Cable connectorsThe rfi lmr-100 series of connectors interconnects RG-316/U-type low-loss coaxial cable. The connectors support all popular interfaces, including bnc, tnc, N, sma, smb, mcx, mini-bayonet, and mini-uhf. Many of the connectors are available in nickel-, gold-, or silver-plated versions. Cable assemblies with the lmr-100 cable and rfi connectors are available in custom lengths.
Automatic crimping machineThe CF 3000-2.5 strips a stranded wire to the exact length, inserts a ferrule on the wire, and crimps it. The 29-pound machine processes up to 1200 conductors per hour. A digital display/reset counter button and a power-indication light-emitting diode is incorporated in the handle. Five different die sets and reels of taped ferrules can be installed or changed in seconds. The five die sets can process 22- to 14-awg stranded pvc-coated wires.
Cable hanging systemThe Saddle allows for the safe placement of Category 3, Category 5, and fiber-optic cables. The cable hanging system can be used in applications where traditional support devices are not appropriate, such as in tight corners or when entering and exiting overhead areas. The Saddle conforms to all building code regulations as well as iso, eia, and csa specifications.
Cable and wire strapsCable and wire management straps come in custom widths, lengths, and colors, and can be printed with company logos. Applications for these straps include telecommunications, utility cords, fiber optics, cable TV, audio, video, and computer network installations. The straps are also available with or without a grommet.
By the Book....When introduced in 1995, the lan Design Manual, published by bicsi (Tampa, FL), was the culmination of months of work by the organization`s Engineering and Methods Committee. The manual included 15 chapters on local area networks (lans), as well as a glossary, bibliography, and index.
Cable Installer TipsMake labels cleaner and easier to readLabels on patch cables often contain smeared or illegible writing. As a result, when these cables are accidentally pulled from their outlets, reinserting them into the proper outlet becomes guesswork. Also, ribbon-type labels are not permissible in some environments, such as cleanrooms.
Poke-throughs combine safety and flexibilityBefore the development of fire-rated poke-throughs, it was necessary to install firestopping material to maintain the fire-retardant capabilities of concrete floors when core-drilling them to run wiring. These firestopping operations could not always be adequately policed, leading code-enforcement agencies to limit this installation practice.
Strategically place voice/data outlets to accommodate equipment cordsWhile most voice/data outlets are placed at an appropriate height on a wall, they often are not strategically placed left or right of center on the wall. Such indiscriminate placement frequently results in higher costs, creating a tripping hazard and leaving an unsightly cord draped across the floor.
Provide larger pathways in side-by-side cable-management racksWhen vertical cable-management racks are placed side-by-side, the brackets on the abutting ends of the racks often cannot accommodate the number of cables running through them. Overloading the small brackets results in kinked patch cords, an aesthetically unpleasing management system, and difficulty in patch-cord identification.
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This IssueNo Image Available Volume 5
Issue 11
November 1997
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