Archived 2016 Lapp Group International Catalog

Appendix Glossary

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

machines and machine configurations operating together (machine groups). The National Fire Protection Association (www.nfpa.org) is the issuer of this important standard. NFPA 79 applies to all electrical and electronic components in machinery with a maximum nominal voltage of 600 V. NFPA 79 was revised in 2006. The aim of this revision was to harmonise NFPA 79 with its European counterpart IEC/EN 60204. Nominal voltage The nominal voltage is the voltage to which the structure of the cable relates in terms of its electrical properties. The nominal voltage is expressed by specifying two AC voltages U 0 /U in V : U 0 = Effective value between an outer conductor and earth (non-insulating environ- ment). U = Effective value between two outer conductors in a multi-core cable or a system of single-core cables. Norms The German Federal Supreme Court gave the following statement on engineering rules on 14.05.1998: Recognised engineering rules are those that are recognised as correct by the theory and have demon- strated their effectiveness in practice. By contrast, according to the BGH DIN standards are only private engineering regulations with the nature of recommendations, which do reflect the recognised engineering rules but lag behind them or could actually be incorrect.

Order length The length of cable ordered by the customer.

OTDR Measuring method for testing glass fibres for faults or transmission quality. OTDR stands for Optical Time Domain Reflectometer. Outdoor cable Cables suitable for outdoor laying in the ground, in pipes, in the air, in rivers and lakes, in mines, on ships, for interior spaces or the most varied of industrial plants, etc. The design of the cable depends on the electrical, thermal, mechanical and chemical laying and operat- ing conditions. Outer conductor Conductors that connect current sources with consumables. For exam- ple, C1, C2 or C3 in a three-phase system but not conductors come from the midpoint or neutral point. The conductor is arranged concentri- cally around the inner conductor of a coaxial pair. Outer diameter Diameter of the smallest circle that will enclose the surface of the sheath.

Numeral identification See → Colour codes/Numerical identification

Outer sheath Enclosed cover for protection of the elements underneath.

Numerical aperture Sine of the maximum possible launch angle of a light waveguide.

Outer sheath On the one hand, refers to the outer covering of a cable. On the other hand, it is the entire optically transparent material in a light waveguide, excluding the core.

NYM These cables (standard cable for fixed installation) are designed for installation above, on and below ground, in dry, damp and wet areas and within walls and concrete, except for direct embedding in shaken, vibrated or compressed concrete.

Overcurrent If the permitted ampacity is exceeded, this is referred to as overcurrent.

Overcurrent protection devices Overcurrent protection devices break the current supply in case of overcurrent. They include overcurrent protective switches and safety fuses. Oxygen index Percentage oxygen content in the ambient air that is necessary to main- tain combustion after removal of a flame. As the natural oxygen content in the air is approx. 23%, materials with an oxygen index of greater than 24 are generally self-extinguishing when the flame is removed. This term comes up primarily in connection with halogen free cables.

O Ohmic resistance

The resistance per unit length records the losses in the metallic con- ductors. The conductor dimensions, material and the temperature determine the DC resistance Ro′. Because of skin effect, the conductor resistance increases as the frequency rises. It also shows a linear increase as the cable length increases.

ÖNORM-Format Austrian format for invitations to tender.

P Pad

Operating supplies All objects needed when using electrical energy, e. g. switch, motors and cables. Operating temperature range The range between the lower (lowest permissible temperature) and upper (highest permissible temperature) limit temperature that may be utilised by the operator. Operating voltage The actual voltage in a grid. This can fluctuate by up to 5%, caused by the alternating use of consumers.

Non-conductive element made of insulating material (PVC) or textile, used to fill up gaps in a strand group. Also known as a dummy core.

Pair Two stranded → cores within a larger strand group (see → Element). The inductive coupling of two parallel conductors is reduced by twisting the two cores together as tightly as possible (→ twist length). Panel mount base Panel mount bases are designed for the feeding through of cables from below. The panel mount base is mounted to control cabinet walls for connecting control or power cables.

Opposite direction of lay See → Stranding

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