IEC 62255-4-2005 pdf – Multicore and symmetrical pair/quad cables for broadband digital communications (high bit rate digital access telecommunication networks) – Outside plant cables – Part 4: Aerial drop cables – Sectional specification

IEC 62255-4-2005 pdf – Multicore and symmetrical pair/quad cables for broadband digital communications (high bit rate digital access telecommunication networks) – Outside plant cables – Part 4: Aerial drop cables – Sectional specification.
1 Scope This sectional specification relates to IEC 62255-1. This standard is applicable to aerial drop cables with or without a metallic screen over the cable core, a thermoplastic jacket, copper conductors, and solid or cellular insulation. These cables are typically available in 2 to 6 pair. These cables are intended for aerial applications and are self-supporting. The cables covered by this specification are differentiated by bandwidth and are classified by having a maximum reference frequency of 30 MHz, 60 MHz, or 100 MHz. 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. IEC 60304, Standard colours for insulation for low-frequency cables and wires IEC 62255-1:2003, Multicore and symmetrical pair/quad cables for broadband digital communications (high bit rate digital access telecommunication networks) – Outside plant cables – Part 1: Generic specification IEC 62255-4-1, Multicore and symmetrical pair/quad cables for broadband digital communications (high bit rate digital access telecommunication networks) – Outside plant cables – Part 4-1: Aerial drop cables – Blank detail specification 3 Terms and definitions For the purposes of this document, the definitions given in IEC 62255-1 shall apply. 4 Installation considerations See Clause 4 of IEC 62255-1.
5 Materials and cable construction 5.1 General remarks The choice of materials and cable construction shall be suitable for the intended application and method of installation of the cable. 5.2 Cable construction The cable construction shall be in accordance with the materials, dimensions, and assembly details given in the relevant detail specification. 5.3 Conductor The conductor shall be a solid annealed copper conductor having a diameter between 0,5 mm and 0,9 mm. Factory joints are permitted. The breaking strength of a joint shall not be less than 90 % of that of an unjointed conductor. 5.4 Insulation The conductor shall be insulated with a suitable polyolefin material. The type of the conductor insulation shall be solid or cellular or any combination thereof. The insulation may be made with or without a solid dielectric skin. The skin material may be different than the base material. Other multi-layer systems may be used. The insulation shall be continuous and shall have a thickness such that the finished cable meets the specified requirements. Joints in the insulated conductor are allowed. Joints shall be free from lumps and reinsulated with a non-hygroscopic dielectric material. The nominal thickness shall be compatible with the method of conductor termination. 5.5 Colour code The colour code of the insulation is not specified but shall be indicated in the relevant detail specification. The colours shall be readily identifiable and shall correspond reasonably with the standard colours shown in IEC 60304. 5.6 Cable element The cable element shall be a twisted pair or quad. 5.7 Cable make-up The cable elements shall be assembled into a circular core so as to provide the required number of pairs. The core of the cable may be wrapped with a protective layer(s) of a non-hygroscopic material.
5.8 Filling compound The core of the cable may be filled with a suitable water-blocking material. Examples of suitable materials are: – polyethylene modified petroleum jelly; – extended thermoplastic rubber; – absorbent thixotropic gel; – superabsorbent polymers with or without a carrier. The material shall be compatible with the cable components with which it is in contact. The type of material shall be indicated in the relevant detail specification. 5.9 Flooding compound A flooding compound may be provided. Examples of suitable materials are: – polyethylene modified petroleum jelly; – absorbent thixotropic gel; – superabsorbent polymers with or without a carrier; – atactic polypropylene. The material shall be compatible with the cable components with which it is in contact. The type of material shall be indicated in the relevant detail specification. 5.10 Screening of the cable core A screen for the cable may be provided. A protective buffer (wrapped, longitudinally applied, or extruded) may be applied under or/and over the screen.