Installation guide

Planning and Designing RIO Cable System
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890 USE 101 00 October 2006
Choosing Coaxial Cables for an RIO Network
Overview Your choice of cables for an RIO network is very important. Semirigid cable offers
the highest performance trunk cable, but it requires professional installation. Flexible
cable is simpler to install but has more signal loss—and thus causes more distance
constraints. RG-11 flexible cable is generally recommended for use as the trunk, but
RG-6 flexible cable may be used as a trunk cable on small networks. RG-6 is used
most often as the drop cable.
Coaxial Cable
Construction
In all cases, we recommend the use of high grade, well shielded industrial cable for
trunk and drop cables on an RIO network. Physically, the cable is a single center
conductor of copper, copper-plated aluminum, or copper-plated steel surrounded by
an outer conductive material, called the shield. The center conductor and shield are
separated by an insulating material called the dielectric. The most common dielectric
material is polyethylene foam. The shield is usually made of aluminum foil and/or
copper braid or some other type of metal braid. The foil provides 100% center
conductor shielding. The shield may have an insulator surrounding it called the
jacket. The most common jacket material is polyvinylchloride (PVC).
Better quality cables use multiple foil and braid shields:
Shield Type Shield Effectiveness
Braid Approximately 50 dB
Foil Approximately 80 dB
Foil + Braid Approximately 95 dB
Foil + Braid + Foil (tri-shield) Approximately 105 dB
Foil + Braid + Foil + Braid (quad shield) > 110 dB
Semirigid > 120 dB
Center Conductor
Dielectric
Shield
Flooding Compound
Jacket
This document provided by Barr-Thorp Electric Co., Inc. 800-473-9123 www.barr-thorp.com