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Optical attached cable (OPAC) is a type of fibre optic cable that is installed by being attached to a host conductor along overhead power lines. The attachment system varies and can include wrapping, lashing or clipping the fibre optic cable to the host. Installation is typically performed using a specialised piece of equipment that travels along the host conductor from pole to pole or tower to tower, wrapping, clipping or lashing the fibre optic cable in place. Different manufacturers have different systems and the installation equipment, cable designs and hardware are not interchangeable. Although lashed cable systems and clipped cable systems have been investigated as a means of attaching optical fibre cables to overhead power lines, wrapped cables were the first type to be developed and are the only type in common use today. Wrapped cable systems were developed independently in the UK (SkyWrap) and Japan (GWWOP) during the 1980s and have been widely used, with installations in every continent except Antarctica. Through licensing and through independent development, wrapped cable systems have also been supplied by French, Italian, German and Russian companies. The installation process for wrapped cables involves passing a drum of cable around and around the host conductor as the carrying device moves across the span. For installation on hosts within 10m of the ground (medium or low voltage overhead lines), it is possible to pull the wrapping machine by hand from the ground below the line. However, a radio controlled power unit using batteries or a petrol engine is normally required when the host conductor is on a high voltage transmission line. Wrapped cables can be applied to earth wires (ground wires, shield wires) on power transmission lines and to phase conductors on transmission, sub-transmission or distribution lines. SkyWrap is the most successful example of OPAC and is used together with more familiar optical fibre cables such as OPGW and All-dielectric self-supporting cable (ADSS) to build communications networks for power utilities == Etymology == The generic International Electrotechnical Commission (IEC) and IEEE designation for attached cable is "OPAC". OPAC can be used in the same sense as the nomenclature "OPGW" and "ADSS". OPAC refers specifically to fibre optic cables and specifically to installations where the host conductor is part of the electricity supply system. Installations using metallic cables (coax or copper telephone cables) or messenger wires as the host are not covered by the term OPAC. The term "Ground-Wire Wound Optical cable" (GWWOP) is sometimes used to describe wrapped fibre optic cables for installation on power lines. and may be a brand name owned by Furukawa Electric of Japan. The Russian language description for wrapped cable technology is "ОКНН" (оптоволоконного кабеля неметаллического навивной) (''in English:'' OCNN = Optical Cable, Non-metallic, coiling or wrapping (''Navivnoj'')). The French language term is "Câble Optique Enroulé" (COE) The name "SkyWrap" is one of three related brand names introduced by FOCAS in 1990 to describe its fibre optic cable products used in the construction of power utility communications networks, the others being ''SkyLite'' OPGW and ''SkySpan'' ADSS. When AFL acquired FOCAS in 2000, the SkyLite and SkySpan brand names were dropped but SkyWrap has continued to be used. Prior to 1992 the brand name was Rayfos. The ''Rayfos'' name is owned by Raychem Corporation, who developed the technology before selling it to FOCAS. ''Rayfos'' is a portmanteau name constructed from "Raychem" and "fibre optic system". 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Optical attached cable」の詳細全文を読む スポンサード リンク
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