|Overhead electrical lines exceeding AC 1 kV – Part 1: General requirements – Common specifications
|CLC/TC 11 - OVERHEAD ELECTRICAL LINES EXCEEDING 1 KV A.C. (1,5 KV D.C.)
This European Standard applies to new overhead electric lines with nominal system voltages exceeding AC 1 kV and with rated frequencies below 100 Hz. The extent of the application of this standard by each country in respect of existing overhead lines is subject to the requirements of the National Normative Aspects (NNA) applicable to that country. The specific definition as to the meaning and extent of a “new overhead line” is to be identified by each National Committee (NC) within their own NNA. At the least, it shall mean a totally new line between two points, A and B. Field of application This European Standard also applies to covered conductor overhead lines and overhead insulated cable systems with nominal system voltage exceeding AC 1 kV up to and including AC 45 kV and with rated frequencies below 100 Hz. Additional requirements and simplifications are specified that apply only for this voltage range. Design and construction of overhead lines with insulated conductors, where internal and external clearances can be smaller than specified in the standard, are not included for lines exceeding 45 kV. Other requirements of the Standard may be applicable, and where necessary NNAs should be consulted. This European Standard is applicable for optical Ground Wires (OPGWs) and optical Conductors (OPCONs). However the standard is not applicable to telecommunication systems which are used on overhead transmission lines either attached to the transmission line conductor/earth wire system (for example wraparound,…) or as separate cables supported by the transmission supports for example All Dielectric Self Supporting (ADSS) or for telecommunication equipment mounted on individual transmission line structures. When such cases are necessary, requirements can be given in the NNAs. This European Standard does not apply to: overhead electric lines inside closed electrical areas as defined in EN 61936-1; catenary systems of electrified railways, unless explicitly required by another standard. Structure of the European Standard EN 50341-1 Normative references, definitions and symbols with their significations are listed in Clause 2 below. In Clause 3, the basis of design according to this standard is given. The standard specifies in Clauses 4 to 6 the general requirements that shall be met for the structural and electrical design of overhead lines to ensure that the line is suitable for its purpose with due consideration given to safety of public, construction, operation, maintenance and environmental issues. Clauses 7 to 11 of this standard consider the structural and electrical requirements that shall be met for the design, installation and testing of overhead line components including supports, foundations, conductors, insulator strings and hardware as determined by the relevant design parameters of the line. Finally, Clause 12 considers the quality assurance requirements during design, manufacturing and construction. Flowchart 1.1 summarises the structure of the European Standard EN 50341-1 and its Clauses 1 to 12.