Keskijohdon

Keskijohdon is a Finnish term used in technical contexts to denote the central conductor of a multi-conductor system. It most commonly refers to the inner conductor of a coaxial cable, which carries the primary signal or power, while the surrounding insulation and outer conductor provide shielding and return paths. The central conductor defines the electrical parameters of the cable, such as impedance and resistance, together with the dielectric and outer conductor.

Etymology and usage: the word combines keskikoht or keskijohto elements meaning center or middle and johto meaning wire or conductor. In Finnish, keskijohdon is the genitive form used when describing characteristics or relationships, for example keskijohdon impedanssi or keskijohdon materiaali. The term is primarily found in Finnish-language electrical and telecommunications literature and may be used alongside more general terms like inner conductor or central conductor.

Technical context: the central conductor is typically a solid or stranded copper element, sometimes tin-coated, sized to meet impedance and current-carrying requirements of the system. In coaxial cables, its properties together with the dielectric determine the characteristic impedance (for example 50 ohms or 75 ohms). In other systems, such as multi-conductor cables or certain RF applications, the central conductor plays a direct role in signal integrity, attenuation, and shielding interactions. The exact specifications of keskijohdon vary by application, standard, and manufacturer.

Broader usage: beyond cables, the concept of a central or main conductor can appear in Finnish discussions of electrical installations, where references to a central bus or main conductor may also appear. Terminology can differ by sector, but keskijohdon generally denotes the core conductive path at the heart of a cable or network.