Structured Cabling Systems

Cabling standards for LANs such as Ethernet are defined by EIA/TIA 568 and ISO11801 for both copper and fiber cabling plants and is usually referred to as a Structured Cabling System (SCS). Simply put, the standards under EIA/TIA and ISO11801 provide a series of requirements for the physical layout of the cabling plant and performance and testing criteria, providing a “structure” so that known performance can be expected when plugging in your network equipment. Properly followed it is the intent of these standards that the SCS will provide a useful life of 10 or more years.

Some of the critical yet practical requirements of these standards include maximum horizontal cable runs of no longer than 90 meters, patch cords not to exceed 5 meters each and 10 meters combined, specific construction of horizontal cable such as 4 pairs UTP and STP of no less than 24 AWG and performance criteria defined as Cat 5e and Cat 6. Both Cat 5e and Cat 6 are capable of supporting networking speeds up to 1 Gigabit/second. For industrial applications Cat 5e is recommended and will meet virtually all needs now and in the future. Patch cords can be of either solid or stranded construction, with stranded cable providing improved flexibility. Currently under development are standards for industrialized versions of copper connectivity offering more robust interfaces to higher vibration, shock, environmental conditions such as IEC IP67 ratings.

These standards also apply to fiber cabling, both Single Mode (SM) and Multi Mode (MM). There are many variations of fiber but the prime advantages offered by either fiber type include noise immunity, longer distances and higher bandwidth capabilities. MM cables can extend from 220 meters up to 550 meters. SM fiber cables can extend up to 40km and beyond! For most industrial applications MM fiber is recommended as the more cost effective solution while still getting most of the benefits of fiber.