Choosing a Cable Tray System

Cable trays often provide a solution for cabling networks that must be upgraded, reconfigured, or relocated. The variety and sophistication of overhead distribution systems offer greater choice in selecting the right cable tray for new construction and retrofit applications. Whether concealed in suspended ceilings or installed in open overhead spaces, cable trays offer a high degree of flexibility, both in terms of locating the components and accessing the cabling contained within them.

Overhead systems include wireway and cable tray systems that are available in single-channel and divided configurations with a variety of sizes and cover and hanging options.

Center spine cable trays consist of a central support member from which extend a series of rungs that support the cable. The tray is suspended from a series of single hangers, rather than the customary trapeze hanger. This configuration allows cables to be laid in and eliminates the need for labor-intensive cable pulling in many instances. It should be noted that not all center spine cable trays are the same. The best designs have screw-in rungs that can be removed and replaced. Rungs should also feature factory-installed end caps to prevent damage to cables and injury to installers. Well-designed center spine cable trays also feature a stiffener bar to reinforce the hanger and offset uneven loads. A version of the center spine tray with rungs on only one side of the spine is available for wall mounting.

Solid bottom cable trays offer an effective way to manage wiring while keeping it accessible, organized, and secure. These systems accommodate large numbers of branch lines and offer high load-bearing capacity. Technicians can install one or more dividers to separate power and data lines and organize cabling. For added cabling protection, solid bottom cable tray can be specified with or without covers. Ventilated louvers can also be specified to facilitate cooling by natural convection while keeping conductors enclosed and protected. Solid bottom cable trays may be hung using either a center rod support, C-hanger, or a two-hanger trapeze configuration; and they can be wall mounted using brackets.

Ladder cable trays offer strength and high capacity and are thus well-suited to heavy-duty power distribution in industrial facilities. Ladder trays, however, do not offer the wire and cable management flexibility of solid bottom or center spine cable trays, since cables must be pulled rather than laid in place.

Wireway is a totally enclosed system that does not include provision for activation of the wiring or cabling contained within. Hinged or screw-on covers provide complete protection, while allowing convenient access to add, remove, or reconfigure cabling. Wireway differs from solid-bottom cable tray mainly in the requirement that the cables be covered.

Some manufacturers offer a range of standard and custom colors for solid bottom cable trays and wireway systems. While color is certainly an aesthetic consideration, it also has practical value in a large and complex facility where colors can serve as guides to the wiring and cabling contained in the system. For example, a facility may run all of its copper cabling in a blue cable tray system and its fiber optic cabling in an orange one to provide instant identification.

Overhead wire and cable management systems provide both operational and systems flexibility. Operation flexibility encompasses the day-to-day or month-to-month changes required for the workplace to keep pace with the functions being performed in it. Systems flexibility enables a facility to accommodate new or expanded communications technologies over the long term. Flexible wire management systems for electronic cabling add value to both new and renovated buildings by lowering operational and long-term systems costs. In today’s complex and competitive environment, electronic cabling involves more than just the cable and connections. Cable tray systems efficiently and economically manage increasingly complex building wiring requirements while offering maximum workplace flexibility.