BS EN 50290-2-1:2005 – Communication cables — Part 2-1: Common design rules and construction
1 Scope
This European Standard harmonises the standardisation of symmetrical, coaxial and optical cables used for the infrastructure of communication, multimedia and control networks. Most of the cables covered by this European Standard are primarily intended to be used in IT networks. However, they can also be used for other applications with the exception of those which presume a direct connection to the mains electricity supply.
EN 50290-2-1 gives the common rules for the design and construction of symmetrical, coaxial and optical cables used for the infrastructure of communication and control networks. It is to be used in conjunction with EN 50290-1 -1 and is completed by generic, sectional, family and detail specifications, as appropriate, to describe in a detailed manner each type of cable with its specific characteristics.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
EN 50290-1 -2 Communication cables – Part 1 -2: Definitions
EN 50290-2-23 Part 2-23: Materials – PE insulation
EN 50290-2-24 Part 2-24: Materials – PE sheathing
EN 50290-2-25 Part 2-25: Materials – Polypropylene insulation compounds
EN 50290-2-26 Part 2-26: Materials – Halogen free flame retardant insulation compounds
EN 50290-2-27 Part 2-27: Materials – Halogen free flame retardant thermoplastic sheathing compounds
IEC 60304 Standard colours for insulation for low-frequency cables and wires
IEC 60028 International standard of resistance for copper
IEC 60793-1 Optical fibres – Part 1 : Generic specification.
3 Definitions
For the purpose of this standard, the definitions given in EN 50290-1 -2 apply.
4 Common design rules
4.1 Materials
4.1 .1 Conductor materials
4.1 .1 .1 Wires and inner conductors
The construction and material of wires or inner conductor shall be specified in the relevant specification.
The conductor shall be either solid or stranded annealed copper. The conductivity of the copper shall be in accordance with IEC 60028. Alternatively, the conductor shall consist of copper-clad steel. The layer of copper cladding shall be continuous, and shall adhere to the steel; the cross-section shall be circular, such that the maximum resistance of the clad conductor shall not exceed that given for copper conductor, in accordance with IEC 60028, by more than a factor of 4,8, 3,5 and 2,8, respectively, for 21 % (minimum), 30 %, and 40 % nominal conductivity grade copper-clad steel.
The percentage elongation at break, when tested in accordance with test methods given in 9.7 shall be not less than 1 %. The minimum tensile strength shall be 827 N/mm², 792 N/mm², 760 N/mm² for 21 %, 30 %, and 40 % grade, respectively.
Alternatively, the conductor shall consist of copper clad aluminium. The layer of copper cladding shall be continuous, and shall adhere to the aluminium, the cross section shall be circular, such that the maximum resistance of the clad conductor shall not exceed that given for copper conductor, in accordance with IEC 60028, by more than a factor of 1 .8. The percentage elongation at break, when tested in accordance with test methods given in 9.6 shall not be less than 1 %. Conductor joints made after the last drawing operation are not allowed.
The stranded conductor shall consist of wires circular in section and assembled, without insulation between them, by concentric stranding or bunching. The individual wires of the solid or stranded conductor may be plain or metal-coated.
BS EN 50290-2-1:2005 – Communication cables — Part 2-1: Common design rules and construction