Included in this category are all types of telephones; auxiliaries such as modems, coil cable, CCTV/CATV cable, and LAN hardware; intercoms; alarms such as gongs and horns; and fiberoptic equipment such as cable, terminations, and splices.
A very important segment of the electrical industry involves the installation and maintenance of telecommunications systems. This equipment, while somewhat specialized, is installed using techniques similar to those used for power and lighting conductors. Termination and test methods, however, differ a great deal. To deal with this rapidly growing industry, several new standards have been established defining cabling specifications and ways in which standards-based wiring and connecting hardware should be installed. They are collectively known as the EIA/TIA Telecommunications Wiring Standards and include the following: EIA/TIA-568, -569, and -606.
Typically, telephone equipment used in residential and commercial structures is modular. Jacks, inline couplers, junction boxes, and handset coiled cord are all connected with hookup wire to form a system. However, there is more of a variation in systems used in industrial locations. Explosion proof or intrinsically safe telephone systems are required in hazardous locations. More rugged equipment is required in others. Sound-powered telephones also have wide application in maintenance operations.
Communications systems within an industrial environment may include paging systems and mobile telephones to allow vehicles and personnel to respond to dispatching calls.
Communication systems in offices
Because of the wide use of computers, today's office environments have a greatly increased requirement for telecommunications. Data must be transferred between workstations, to mainframes, and to remote locations. Local area networks (LANs) provide the means of communications within a facility. Specialized equipment such as cabling systems, jack panels, connectors, and multip in plugs have been developed to serve these networks.
Broadband network expands the capability of the LAN even further by providing video, as well as voice and data communications. It uses CATV technology and coaxial cable, along with signal splitters, amplifiers, and other similar equipment.
Hybrid equipment is available for telecom services: flush outlet plates that combine 120V receptacles,telephone jacks,and broadband connectors. Underfloor raceway systems are being expanded and barriered to route the varied cable.
Optical fiber technology is having a dramatic impact upon teledata services. Starting with the cable, this technology utilizes specialized equipment and tools. Because of the optical fiber's characteristics, pulling equipment, lubricants, and installation within ducts are different. Innerduct is used to subdivide main underground duct runs. Exclusion of water is critical, thus sealing the system is given more attention. Termination and splicing the fiber also involves the use of different equipment and fittings. Specialized distribution panels are available to convey fiberoptic-delivered signals to their destination within a facility.
New telecommunications standards
Telecommunications wiring should be properly planned and installed to assure a long and useful service life. In addition, all of the nonpower wiring in a building should be treated as a single concern that crosses architectural, structural, and electrical disciplines. These two concepts are the driving forces behind the development of a set of Electronic Industries Association/Telecommunications Industry Association (EAI/TIA) standards. The three completed standards are as follows.
* EAI/TIA-515 Commercial Building Telecommunications Wiring Standard;
* EAI/TIA-569 Commercial Building Standard for Telecommunications Pathways and Spaces; and
* EIA/TIA-570 Residential and Light Commercial Telecommunications Wiring Standard.
These standards are in full conformance with the NEC, the NESC, the Life Safety Code, and the Uniform Building Code. They do not replace other existing code.