Housings, telecommunications equipment

Telecommunications closet (TC) An enclosed space for housing telecommunications equipment, cable terminations, and cross connects. The closet is the recognized cross connect between the backbone and horizontal cabling. 

PC/PET and PC/PBT blends offer high strength, toughness (including at low temperature), chemical resistance, excellent UV stability along with improved flame retardancy and colorabihty. They find use in telecommunications equipment for marine radio housings, antenna housings and bases, and cellular telephone handsets. 

Telecommunications equipment is usually housed in a shelter to protect it from wind and foul weather. Shelters are structures without windows that can be climate controlled and contain a large amount of electronics, computers, and other equipment such as transformers. 

The electrically conductive polymers have their greatest use in EMI-shielded casings and protective housings of electronic and telecommunications equipment, where they have rapidly substituted metal because of their low weight and easy workability. Steel fiber is mostly used in filled conductive polymers intended for EMI-shielding applications, which will be discussed below. 

Several sites built to house telecommunication stations, where the antennas, satellite aerials, and all the equipment required for the broadcasting of signals are located on... 

Protectors of telecommunication equipment, often mounted on the sides of homes or in basements, which provide electrical protection to the telecommunication equipment user against lightning and power faults, are exposed to environments similar to those of the aerial plant. Some of these protectors, which include a stressed copper alloy cap and cage, are placed in a phenolic housing. Ammonia or ammonium compounds can cause stress-corrosion cracking (SCC) of some of the stressed copper-base alloys, resulting in failure of the protector. 

KR 2450, KR 2456, KR 2460 - flame retardant rated V-0, rmreinforced, increasing heat distortion temperature (housings for telecommunications equipment, electrical parts)... 

The market for telecommunications equipment is becoming increasingly competitive and attractive appearance is essential so that plastic housings offer the possibility of producing attractive shapes in a range of colours at relatively low cost. 

The highest-volume FR in use worldwide, TBBPA, is used mainly as a reactive flame retardant in epoxy resins for printed circuit boards in computers and telecommunications equipment (Covaci et al. 2009). In reactive applications, TBBPA is covalently bound into the polymer in products and is not expected to migrate from the product. However, TBBPA is also used as an additive to circuit boards for low-energy applications such as remote controls and video recorders as well as the plastic housing for electrical and electronic equipment such as computer monitors and printers (Covaci et al. 2009). Both additive- and reactive-treated products have been shown to release TBBPA and metabolites into the environment (Bimbaum and Staskal 2004). 

Polycarbonate is also applied to business and telecommunications equipment, usually in the form of a blend with PBT. It is used for data input keyboards, housing covers for computers, desktop calculators and magnetic discs. PC and PC/PBT blends are also used for mobile telephone housings. PC is valued in these items for its high impact strength, flame retardance, high heat resistance and good surface finish. 

Multinational firms played a vital role in the international technology transfer. ITT SEL, a German affiliate of the US telecommunications equipment firm ITT, developed the digital spread spectrum broadband system CD900, which was defeated at the CEPT conference in 1987 by the narrowband concept that finally became the GSM standard. The project team came from the defense-communications department and used the ITT in-house knowledge base, in particular knowledge on the radio system used in AW ACS surveillance planes. 

Poly(phylene) oxides are widely used for office equipment housings, various industrial components, automotive, telecommunications and appliances. Due to the inherent chemical structure, PPO exhibits unusually low moisture absorption, providing excellent insulating properties and difnension stability over a wide range of humidity. The properties are classified into five categories and described below. 

Electrical electronics connectors, chassis and housings for electrical and electronic equipment, sliding parts in video recorders, safety switches, disk supports in CD players, induction motor supports, telecommunications parts. 

This section examines the use of engineering and high performance plastics in electrical equipment and electronics industries, including telecommunications. Applications covered are electronics parts and components such as switches and connectors, business and electrical equipment housing, wire and cables, electrical lighting parts and lenses. 

PPO/PPE blends are used in business and computer machine housing, structural and interior components in electrical equipment and telecommimications equipment. PPO/PPE blends are suitable for various telecommunications applications such as enclosures, switchgear, networking devices, flexible circuitry and cable and wire extensions. Key properties are their good chemical resistance to most solvents, fuels and other contaminants, excellent processability, impact performance at extreme temperatures, and thin wall performance that can reduce cycle times. 

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