BS EN 50122-2:2010

1 Scope
2 Normative references
3 Terms and definitions
4 Identification of hazards and risks
5 Criteria for stray current assessment and acceptance
6 Design provisions
7 Provisions for influenced metallic structures
8 Protection provisions applied to metallic structures
9 Depots and workshops
10 Tests and measurements
Annex A (informative) - Measurement of track characteristics
Annex B (informative) - Stray current assessment - Rail
         insulation assessment using rail potential
Annex C (informative) - Estimation of stray current and impact
         on metal structures
Annex ZZ (informative) - Coverage of Essential Requirements of
          EC Directives
Bibliography

Defines requirements for protective provisions against the effects of stray currents, which result from the operation of d.c. traction systems.

This European Standard specifies requirements for protective provisions against the effects of stray currents, which result 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 European Standard only deals with stray currents flowing from a d.c. traction system. This European 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, material transportation systems. This European Standard does not apply to: mine traction systems in underground mines, cranes, transportable platforms and similar transportation equipment on rails, temporary structures (e.g. exhibition structures) in so far as these are not supplied directly from the contact line system and are not endangered by the traction power supply system, suspended cable cars, funicular railways. This European Standard does not specify working rules for maintenance.