Q: We have a question about cable stress due to tie wraps and bridle rings. What types of cable-support mechanisms are available to eliminate stress and kinking with Category 5 cabling?
Professional Cabling Service Inc.
A: Numerous manufacturers of cable-hanging hardware can provide you with cable supports that will not kink or deform the cable jacket. The Cabling Installation & Maintenance 1997 Online Buyer`s Guide (www.cable-install.com) lists seventeen such manufacturers.
In a pinch, you can make these devices yourself. I do not recommend this as a cottage industry, but if you are in need of a few hangers for a few cables and the supply houses are closed: Cut short lengths of 1/2-inch split fiber duct, making the sections 4 to 12 inches long. The split should be on the side near the top and not at the bottom or your hanger may relax over time and your cables will be on the ceiling. Attach the cable hanger to the concrete decking with a powder-actuated fastener. This has proved to be a great use for scraps of plenum-rated fiber duct.
A word of caution, however: The plastic innerduct commonly used for underground or outside-plant construction may not have appropriate fire-safety characteristics for use within buildings.
Donna Ballast is a communications analyst at the University of Texas
at Austin and a bicsi registered communications distribution designer (rcdd). Questions can be sent to her at Cabling Installation & Maintenance or at PO Drawer 7580, University of Texas, Austin, TX 78713; tel: (512) 471-0112, fax: (512) 471-8883, e-mail: firstname.lastname@example.org.