Archived 2016 Lapp Group International Catalog

Appendix Glossary

ÖLFLEX ® ACCESSORIES FLEXIMARK ® SILVYN ® SKINTOP ® EPIC ® HITRONIC ® ETHERLINE ® UNITRONIC ® APPENDIX

VDEW Abbreviation for Vereinigung Deutscher Elektrizitätswerke [Association of German Electricity Plants]. Velocity of propagation Transmission speed of the electrical energy in a length of the cable compared to the light speed in free space. Usually expressed as a percentage. Volt Electrical unit of measure for voltage. 1 Volt is the voltage produced by a current of 1 A with a resistance of 1 Ohm. Voltage = Resistance x Current Voltage-level classes We refer to four voltage levels. Everything that is < 1000 Volt (< 1 kV) belongs to the low voltage class. Voltages > 1 kV are classed as high voltage. In practice (no statutory specification), the high voltage class is divided into: Medium voltage 1 kV – 30 kV, high voltage 50 kV – 150 kV, extremely high voltage 150 kV – 400 kV. There are several different voltage levels within these classes. Voltage, tension Electrical unit of measure, measured in Volts, i. e. Voltage = Resistance x Current. VSWR (Voltage Standing Wave Ratio) Ratio of the transmitted signal voltage to the reflecting signal voltage measured along the transmission path. Vulcanising Technological process in which temperature, pressure and the use of sulphur compounds, for example, cause the molecules in rubber to form cross linkages. It is this process that gives rubber its permanent elasticity and makes it suitable for industrial use (see → Cross linking). Volt meter Instrument for measuring voltage.

(a is the core radius, l is the light wavelength). In practice, waveguide dispersion always acts in conjunction with material dispersion; its overall effect is referred to as chromatic dispersion. Wear resistance The characteristic of a cable, wire or material to withstand surface wear. WEEE directive Under electrical and electronic equipment legislation (ElektroG in Germany), the WEEE directive governs the withdrawal of electrical and electronic products. Wire drawing Cold forming process, in which a sequence of increasingly small draw- ing dies (carbide cores or diamonds) gradually reduce the cross-sec- tion of pressed wire or wire rod. Wire termination technique Depending on the application, different wire termination methods can be chosen. Where ease of service and maintenance is required, a screw fitting is used. If large numbers of plug connectors with a reliable connection method are required, crimping is the best choice. A cage clamp combines ease of service with reliable wire termination, although the space required per contact for the wire termination is the highest of all the methods described here. Wire–wrap connection This is an electrical connection made without soldering. The contact is made by wrapping a bare copper wire around a square rod made of bronze, brass or silver under high tension (also known as cold welding).

Wiring cable Cable for wiring equipment, control cabinets etc.

Wiring system Wiring systems are made up of a variety of individual elements, such as cable sheathing, contact plugs, connector shells, seals, fixing ele- ments, etc. In a car, the wiring system connects the electromechanical and electrical components and guarantees the transmission of infor- mation from and between the control units, as well as for the supply of energy to the consumers (engine, relay, lighting, etc.).

W Wall thickness The thickness of the insulation or sheath.

Working current, service current The maximum permissible current that may be transmitted.

WAN WAN is the abbreviation for Wide Area Network. This is a large network, which can extend worldwide. WANs normally connect LANs (Local Area Networks) via telephone cables. Routers and gateways connect the LANs using different technologies. WAN is a wide area transmission network for connecting distance users to a central network using pub- lic cables.

Woven cable Several conductors running parallel which are held together using a thin sheath. See also → Flat cable.

Z Zinc In the cable industry, galvanised steel tape or steel wire are used as the armouring material (→ Armouring) to protect against corrosion. ZVEH Abbreviation for Zentralverband der Deutschen Elektrohandwerke e.V. [Central Association of German Electrical Trades] (Germany). ZVEI Abbreviation for Zentralverband der Elektrotechnik- und Elektronik Industrie e.V. [Central Electrical Engineering and Electronics Industry Association] (Germany).

Watt Electrical unit of measure for power V x A = Watts (VA).

Wave lengths Length of a full wave oscillation (period). In optical signal technology, three wavelength ranges are normally used – 850 nm, 1300 nm and 1550 nm. Waveguide dispersion The dispersion that occurs with non-monochromatic light sources because the a/l relationship and, as a result, field distribution and group speeds of the modes in a light waveguide are wave dependent

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