Planning for the future needs of cable containment

As the development of IT systems continues to match the demand for increased speeds and greater network capacity, high-tech structured wiring and cabling networks are becoming commonplace. Although providing new opportunities for contractors and installers, it is essential that the containment for these latest-technology installations can meet future as well as current requirements. STEVE DAVIS explains.There is no question that of all the areas in which the electrical installation industry has operated over the last few years, that described broadly as IT or information technology has been the fastest-moving and seen the greatest growth. There is also a seemingly insatiable demand by industry and commerce for greater data-processing speeds and higher network capacities. This has set the pace of development of systems and products by manufacturers and suppliers throughout this specialised area. Saturation As more users demand faster access to large volumes of data, local-area networks can rapidly reach saturation. The transmission capacity of a system is limited by its bandwidth. This in turn depends on the transmission medium, which can range from basic copper wires, through coaxial cables to advanced twisted pairs and optical fibre cables. As operating speeds and data throughput increase, even Category 5 cables cannot transmit 1000 Mbyte/s Ethernet over twisted-pair copper conductors. This has led to the introduction of enhanced Cat5e and Cat6 cabling, which has enabled systems to be upgraded. This allows operation at frequencies above 250 MHz, while more advanced Cat7 cables are being introduced to provide high performance over 600 MHz channels. Opportunities Manufacturers are continuing to develop new products and components to meet the spiralling demands. The installations that form the infrastructure on which entire strategic networks are based, are not only creating potentially important new opportunities for electrical contractors and installers, but also possible pitfalls. Even when operating under the tightest budget constraints it is quite unacceptable to lay unprotected data-communications cables directly onto a bare under floor or other surface. This practice exposes networks to a variety of risks and potentially expensive damage from a wide range of causes. In addition to negating manufacturers’ warranties and necessitating costly replacement cabling, unscheduled IT network outages and interruptions to mission or safety-critical systems can have potentially disastrous or unacceptably costly consequences for both contractor and customer. Underfloor solutions such as low-smoke zero-halogen water-resistant polymer matting are designed for laying cables under raised floors, minimising the risks. Expansion Whilst cable-management systems can be selected for their aesthetic appearance and ability to be discreetly installed to complement the working environment, it is essential to ensure that the system provides adequate capacity for future network expansion and possible system upgrades. It is therefore vital that designers, consultants, specifiers and installers give sufficient priority to the choice of cable-management system to protect and ‘future-proof’ expensive high-technology installations. Modern surface-mounting cable-containment systems are designed to meet relevant EIA/TIA, ISO/IEC and Cenelec Standards requirements. They also meet the requirements for minimum bend radii for Cat5e, Cat6 and fibre-optic cables. Cable-containment systems purpose-designed for fibre-optic cables are now available in zero-halogen, fire-resistant Noryl material. As well as meeting minimum bend radii requirements, cable-management systems are also usually required to carry wiring for mains power, lighting and other electrical services such as building controls, fire and security systems.

Not only are Cat6 cables thicker that those of a lower specification, but their back boxes are also deeper — so future proofing involves planning for increased capacity.

All data-communications cabling should be physically separated from mains wiring with adequate screening between compartments to prevent possible data-corruption. For ease of installation, trunkings are available with pre-drilled centre compartments which allow data cables to pass through the dividing wall to the data outlets. Steel dividers with pre-punched knockouts ensure screening is maintained and compliant with EN50174-2. Cat6 and the very latest 10 Gbit/s Cat6 and shielded data-communications cables have a greater cross-sectional area than even Cat5e or other lower categories. This increased size means that the cable-management system must have a larger capacity compared with conventional products. This is necessary not only to meet the requirement for current cabling density but also to future-proof the system. Pulling additional new cables through trunking with inadequate free space will result in cabling damage and network degradation. Internal space As well as providing sufficient internal space for cables, the containment should also be capable of accepting the new Cat6 RJ45 connectors. Now becoming the preferred option with contractors and installers, Cat6 connectors are significantly deeper than those used with Cat5e. Solutions range from trunking systems with 50 mm-deep back boxes to floor boxes with more space above the accessory plate to allow for the longer-booted Cat6 patch cords. The latest purpose-designed cabling containment systems of this type not only simplify the initial installation in leading-edge data-communications networks, but also provide the opportunity for lucrative future system upgrades as cable technologies respond to network demand in the high-growth IT sector. Steve Davis is business development manager with Mita (UK) Ltd, Bodelwyddan Business Park, Bodelwyddan, Denbighshire LL18 5SX.

Related links:

• www.mita.co.uk