Title: Regional aspects on creation of NNA for new standard for overhead lines EN 50341

Convenor: Kresimir Bakic, Slovenia

The new CENELEC (CLC) standard (EN 50341-1) for design and construction of overhead lines above 1 kV AC from December 2012 obligated members of CLC to prepare National Normative Annexes (NNA) reflecting national practices. In general, these NNAs include special national conditions (i.e. weather conditions), legal deviations and national complements. Due to the novel approach in designing considering reliability and increasing load on lines as well as new technologies in OHLs, some SEERC members expressed common interest to set up a working group with intention to exchange information on this important topic.


  • Basic principles for new designing approaches (based on EN 50341-1)
  • Comparison Action on lines comparison (wind loads, ice loads, combination)
  • Comparison of electrical requirements (clearances, corona effect, EMF)
  • Standardization of conductors (classical and HTLS)
  • Regional particularities
  • Report