DIN EN 50122-2:2011-09

This standard specifies requirements for protective provisions against the effects of stray currents resulting from the operation of d.c. traction systems. As experience for several decades has not shown evident corrosion effects from a.c. traction systems and actual investigations are not completed, this standard only deals with stray currents flowing from a d.c. traction system. This standard applies to all metallic fixed installations which form part of the traction system, and also to any other metallic components located in any position in the earth, which can carry stray currents resulting from the operation of the railway system. This European Standard applies to all new d.c. lines and to all major revisions to existing d.c. lines. The principles may also be applied to existing electrified transportation systems where it is necessary to consider the effects of stray currents. It provides design requirements to allow maintenance. The range of application includes railways, guided mass transport systems such as tramways, elevated and underground railways, mountain railways, trolleybus systems, and magnetically levitated systems, which use a contact line system, as well as material transportation systems. The responsible Committee is AK 351.2.1 "Sicherheit, Erdung, Schutz, Streuströme" ("Safety, earthing, protection, stray currents") at Subcommittee UK 351.2 "Ortsfeste Anlagen" ("Fixed installations") of the DKE (German Commission for Electrical, Electronic and Information Technologies) at DIN and VDE.