Cable management for voice/data/video (VDV) is a very important element in an infrastructure and belongs just about everywhere there is cable to be laid. In addition to racks and enclosures, many types of cable management solutions abound, to fit almost every field condition—above, below, around, in, and through.
Many solutions provide capacity for both VDV wiring and power wiring in one system, some with provisions for keeping line voltage separate from low-voltage runs.
VDV cable management support and distribution options include conduit, metallic and non-metallic surface raceway, cable tray, ladder tray, floor boxes, in-floor boxes, wall boxes, poke-through devices, power poles, underfloor duct, baskets, one-side and center spine trays, hooks, bendable metal systems, wire mesh baskets, and flexible nylon mesh.
To accommodate evolving telecommunications technology and sprouting customer needs, it is prudent to use systems accessible for easy moves, adds, and changes (MACs) without disruption or with minimal disruption to end-users.
Cable tray is available in many materials, including steel, stainless steel, fiberglass and aluminum (often the material of choice because it has the best strength-to-weight ratio and is fast to install). The most common finishes for steel cable trays are mill galvanized or hot-dipped galvanized after fabrication.
In some installations, you may have room to specify individual trays for VDV wires, separate from power cables, either to accommodate code requirements or to prevent any signal interference. If space is limited, dividers may provide a similar function.
Because they do not generate heat as energized power cables do, low-voltage cabling can be stacked in cable trays. Low-voltage cabling capacity depends upon loading area and volume, rather than just system width. Manufacturers are recognizing the need for deeper loading systems.
To accommodate low-voltage cable installations, Cooper B-Line has added options to several of its cable tray systems, including the Redi-Rail two-side rail aluminum cabling support system. For new installations, the new H17AR rail size offers 6-inch loading depth (the maximum allowed by the National Electrical Code (NEC)).
For existing installations, the company offers Rail-Risers, which bolt to pre-punched holes in the side rails and convert to a 4- to 6-inch fill depth. Redi-Rail is available in ladder-type, solid-bottom, and vented-bottom straight sections and fittings.
The continuous pre-punched holes serve as splice connection holes, alternate holes for repositioning screw-in/screw-out rungs, and attachment locations for accessories to include the Rail-Risers.
Chalfant Cable Trays COM-TRAY is a modular cable tray system for under raised floors in computer and communications installations. Compatible with the 2- by 2-foot grid post system of raised floors, the galvanized steel trays, with a standard load depth of 6 inches, are available as 6-, 12-, and 18-inch-wide straight sections up to 12 feet long, with optional covers.
Tees, crosses, elbows, splice plates, and reducers are available for configuring virtually any cable routing pattern. The segments bolt together, eliminating field cutting or drilling. The system, which can be elevated off the floor from 2 to 8 inches, is also available, optionally, in ventilated and ladder designs.
HellermannTyton’s Lightguide Fiber Protection System is a fully enclosed ducting system for isolating, routing, and protecting fiber optic cable in central offices, local area networks (LANs), telecommunications rooms, or wherever cable is run from the building entrance to its termination point.
The nonmetallic system, featuring complete lay-in capability and easy access and tracking, provides a smooth, protective surface and channel to prevent fiber kinking, cutting, and associated signal loss. The system, which mounts with metal hardware onto existing equipment such as bays, cable racks, unistrut, and threaded rod, features over 40 connectors and channels that accommodate a range of system sizes.
Wire mesh cable trays are lightweight and easy to handle and modify in the field. Typically, installers can clear obstacles by using a cutter or a more specialized tool to trim pieces of wire and bend the tray. Various types of connectors join the pieces to navigate corners and make tees or crosses. Generally, the trays come in a 2- by 4-inch grid.
OBO Bettermann Wire Mesh Cable Tray System is available in 2- and 4-inch loading depths with widths ranging from 2 to 24 inches. The product, which features a variety of standard mounting options and meets all standards for UL grounding classifications, is suitable for wall and underfloor applications as well as ceiling applications. All bends, crossovers, angles, and tees can be field modified, for easy routing adaptability, both in new construction and in retrofit projects.
Standard finishes include zinc electroplated, stainless steel, hot-dipped galvanized, and powder coated.
T.J. Cope, Inc.’s CAT-TRAY welded wire mesh cable management system, available in nine widths, offers self-splicing bars, welded to one end of the tray, which speed connection of tray sections.
For straight runs that conform to UL grounding standards, the installer bolts a special clip onto the connecting end of each bar to maintain electrical continuity. For situations where the self-splicing bar is not applicable, a new rapid splice bar offers fast clasp-type connecting without nuts and bolts. Notched pedestal brackets, U-bolts, and nuts are available for installing the baskets on flat or corner edging of pedestal legs under raised computer floors.
MPHusky Techtray features a tighter-than-typical 2- by 2-inch grid that provides twice the support surface of the usual 2- by 4-inch grid and includes a pair of splice plates and necessary nuts and bolts with each straight section. Available in widths from 2 to 24 inches and depths of 1 to 6 inches, the product, which is also used in overhead and underfloor applications, features corner connectors without any sharp edges that can also be used on tees or crosses. Installers can also field fabricate fittings by cutting wires and using clips to hold segments together.
GS Metals Flextray Cable Management System, a lightweight, wire-basket-style cable tray system suitable for underfloors or hanging from the ceiling and available in various depths and widths, features total on-site flexibility. Using two specialized proprietary installation tools, installers cut and bend the wire mesh to create drops, bends, climbs and intersections, attaining finished edges with no sharp points.
Special Conduit Attachment Fittings, which come unassembled and are available in four diameters ranging from ½ through 1¼ inches, facilitate quick attachment of conduit to the tray and neat cable drop through the conduit fitting.
Cable Management Solutions (CMS) 501 Series Wall Snake, part of the company’s Snake Tray line of flexible, open steel cable trays that are completely bendable by hand without tools or the need to cut wires, is a perimeter wall mount solution suitable for long linear installations where space is at a premium, such as above the ceiling grid. The trays are designed to allow direct attachment to a wall using mounting rings that run along the center spine, eliminating the need for additional brackets or hanging hardware. Available in 4-, 9-, and 25-square-inch pathways, the trays hang with standard fasteners.
Suitable for raised access floor installations, Cablofil Inc.’s new Under Floor Support Clamp, UFCN, attaches to the company’s FAS Profile under-floor supports that, in turn, secure trays from the Cablofil cable management system. Featuring a snap-on-and bolt design, the corrosive-resistant clamp attaches to square and round support posts in raised access floor installations, for easy height adjustments. The 2-inch-deep cable tray uses a proprietary fast-assembly system (FAS) that features bending of the anchoring tabs on the wire to secure the mounting of the tray without need for screws, bolts, or any tools beyond a screwdriver.
Arlington Industries’ The Hoop, a nonmetallic high-speed cable ring for communications cable, available in two sizes and suitable for horizontal or vertical mounting, has a 5/8-inch bearing surface and comes with or without a built-in ¼-20 screw for easy attachment to a beam clamp. The 2-inch diameter Hoop supports a 25-pound load; the 4-inch unit supports twice that. The positive ring locks tight to hold cable in place and unlatches with a screwdriver to open the hoop and lay in more cable, according to the manufacturer.
Hilti’s powder-actuated X-JH Cable Hanger and X-RH Rod Hanger feature quick- mounting support for VDV cable. For easy attachment in ceiling and wall applications, each product comes pre-assembled with a mounting bracket, and a pre-mounted powder-actuated pin.
The installer removes the assembly from the box, sets the fastener into a Hilti powder actuated tool, suitable for use in concrete, steel and masonry, and presses the trigger to make the fastening. The X-JH Cable Hanger comes in three sizes, ¾, 15/16, and 2 inches; the X-RH Rod Hanger, which accommodates smooth pencil rods, comes in ¼- and 3/8-inch sizes.
Speedy Products, Inc. offers an efficient way to mount voice/data cables in installations using threaded rods. The UL-listed, plenum-rated system uses a Sammy Super Screw to attach the rod and a 2-inch Sammy Saddle snap nut and hook cable hanger. The screw, available for ¼-, 3/8-, and ½-inch rod and capable of drilling through wood, steel, concrete, and drywall, is self-drilling and tapping, except in concrete, which requires pre-drilling. The saddle, which snaps onto ¼- and 3/8-inch rod, can hold up to 35 Category 5 wires. Up to five saddles can be hung per foot.
The new Plenum Pier, from Erico, Inc., supports telecommunication cabling and piping in air handling spaces. Suitable for underfloor and clean room applications, the solution keeps services off the floor and provides support independent of raised floor pedestals. The product consists of a block of white, closed cell polyethylene foam that absorbs vibrations and shock and accommodates expansion and contraction of piping. Yellow chromate channel is bonded into the block of foam, supporting the use of standard strut clamps and accessories.
Surface raceway is a good retrofit option for running VDV wiring between the points where the wires enter the surface of a wall or ceiling and the termination points at the receptacles and switches, without disturbing finished walls or running exposed conduit.
A typical system for VDV consists of steel, aluminum, or plastic (PVC) raceway base with single- or multiple-channel configuration, covers, fittings designed with the gradual radii elbows that Category 5 and Category 6 wiring require, and termination hardware. (Lightweight and easy to cut with a hacksaw or chop saw, PVC raceway is an increasingly popular choice.) The dividers, built-in or optional add-ons, are useful to separate multiple VDV runs or separate VDV runs from power runs.
The Siemon Company standards-compliant Perimeter Raceway System, designed to work with the company’s work area connectivity products, consists of a two-piece plastic hinged extrusion, in three lengths, and available in three sizes for up to two, six, or 16 cables. The cover locks in the open position, forming a trough to retain cables during installation.
Ten perimeter fittings are available, including adapter fittings that provide aesthetic transition to the raceway from the ceiling, floor, or surface mount boxes, and inside and outside corner fittings, elbow fittings, and Tee-fitting and backplate that ensure maintenance of the minimum bend radius fiber and copper cables require.
Designed with increased (1.6-inch) bend radius control for high performance copper and fiber-optic cabling and open channel capacity for up to 148 CAT 5 cables, Panduit Corp.’s TG-70 surface raceway is a large multi-channel capable system for routing, protecting and concealing VDV and power cabling.
Sporting the same look as other Panduit raceway systems, the rigid, tamper-resistant, PVC raceway, which is UL-5A listed to 600V, can mount NEMA standard faceplates or Panduit Snap-On faceplates directly to the channel. Inside and outside corner fittings adapt (between 83 and 135 degrees, 84 to 139 degrees, respectively) for unique room designs and wall angles.
Fire-rated poke-throughs penetrate a fire-resistive (concrete) floor structure for installation of communications and/or electrical cables. Suitable for renovation and retrofit applications where a flexible, unobtrusive cabling infrastructure is desirable, poke-throughs may be classified as through-floor and open space solutions.
Poke-throughs provide capacity and flexibility for data/communications cabling to individual workstations or work areas, reception areas, training centers, and other specialized spaces. Because they pass through holes core-drilled through the concrete floor, they need to incorporate fire-stopping material that, in the event of a fire, would maintain the fire rating of the floor.
The latest generation poke-throughs include one or more rings of intumescent material around the conduit stem at slab level. The material, when exposed to high temperatures of a fire, expands to fill any space between the slab and the fitting, blocking flames and heat and preserving the floor’s fire rating. (The fire classification of each poke through identifies the limits of the size and number of conductors in each.)
In new installations, poke-thru spacing should, by UL requirement, be minimum of two feet on centers and not exceed in density more than one every 65 square feet of floor area in each span.
Flush and raised activations are available. Some poke-throughs combine communications outlets with power receptacles. A new UL requirement, anticipated to be in effect in 2003, requires that poke-throughs installed over carpeting be scrub watertight (meaning they will need the appropriate gasketing to repel water from power washers).
Providing unobtrusive appearance and maximum flexibility should requirements change, Hubbell Wiring Device-Kellems offers a 4x4 Flush Fire Rated Poke-through Fitting that combines up to four modular jacks that mount flush to the cover and four power receptacles with two-circuit wiring capability. The “4x4” refers to the device’s four insulated 15-ampere, 125V receptacles and the fact that it can have up to four Category 5 jacks.
The units, available as one- or two-piece fittings, are UL Listed for floors with a one- to four-hour fire rating. All models feature two internal spurs fastened onto the fitting for securing it in a cored hole when the fitting is installed from above, eliminating need to secure the fitting from the floor below. The spurs are removable if the poke-through needs to be relocated.
Suitable for large capacity installations, The Wiremold Company’s flush quad Walker RC4 Series Poke-thru provides four multimedia data/communication connectors and two dual-circuit, 20 amp duplex receptacles wired on individual circuits with separate neutral and ground wires. For maximum data/communications flexibility, the Poke-thru uses a nonmetallic bracket that accepts a full range of flush and recessed modular connectivity inserts for UTP, fiber optic, coaxial, video and audio connections.
Individual power receptacle slide covers snap in place when the receptacles are inactive to prevent dirt and debris from entering. Featuring “step on it” installation, the series installs very quickly, noted the company.
Designed for high-density data cabling applications such as modular furniture partitions and data lab, the Steel City FPT-400-Data poke through, by Thomas & Betts, can accommodate up to 14 Category 5e data cables.
The UL-listed device, which requires a 3-inch drill for installation, is supplied with the necessary intumescent material to ensure a four-hour fire rating. The device accepts a duplex data adapter for flush-mounted RJ-jacks. A range of cover choices is available, including black, gray and ivory nonmetallic finishes and brass and brushed aluminum metallic finishes.
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