IEC 61156-5-2020 Multicore and symmetrical pair/quad cables for digital communications – Part 5: Symmetrical pair/quad cables with transmission characteristics up to 1 000 MHz – Horizontal floor wiring – Sectional specification.
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 61 1 56-1 apply.
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4 Installation considerations
4.1 General remarks
Installation considerations are defined in IEC 61 1 56-1 :2007, Clause 4.
4.2 Bending radius of installed cable
The bending radius of the installed cable shall not be less than four times the outside diameter of the cable.
4.3 Climatic conditions
Under static conditions, the cables shall operate in the temperature range from –40 °C to +60 °C. The conductor and cable temperature dependence is specified for screened and unscreened cables and should be taken into account for the design of an actual cabling system.
Other temperature ranges may be specified in the relevant detail specification.
Under static conditions, the cable shall operate at least in the temperature range of the environment from –20 °C to +60 °C.
The attenuation increase due to the elevated operating temperature (temperature of the environment) is described in
In the case of application of remote powering, the maximum temperature of the conductor shall not exceed the maximum operation temperature under static conditions in order to maintain the integrity of the dielectric material performance which is aligned to the environmental temperature range.
Extended temperature ranges are permitted and may be specified in the relevant detail specification.
5 Materials and cable construction
5.1 General remarks
The choice of materials and cable construction shall be suitable for the intended application and installation of the cable. Particular care shall be taken to meet any requirements for EMC and fire performance (such as burning properties, smoke generation, evolution of halogen gas, etc.).
The cable construction shall be in accordance with the details and dimensions given in the relevant detail specification.
5.2 Cable construction
5.2.1 Conductor
The conductor shall be a solid annealed copper conductor, in accordance with IEC 61 1 56-1 :2007, 5.2.1 and should have a nominal diameter between 0,4 mm and 0,65 mm.
A conductor diameter of up to 0,8 mm may be used .
5.2.2 Insulation
The conductor shall be insulated with a suitable material. Examples of suitable materials are:
– polyolefin;
– fluoropolymer;
– low-smoke zero-halogen thermoplastic material.IEC 61156-5 pdf download.