20/30430757 DC

This standard 20/30430757 DC BS EN 50122-1. Railway applications. Fixed installations. Electrical safety, earthing and the return circuit is classified in these ICS categories:

• 29.280 Electric traction equipment
• 29.120.50 Fuses and other overcurrent protection devices

This document specifies requirements for the protective provisions relating to electrical safety in fixed in-stallations associated with AC and/or DC traction systems and to any installations that can be endangered by the electric traction power supply system. This also includes the requirements which are present at the in-terface with the live parts on the outside of the vehicles. It also applies to all aspects of fixed installations that are necessary to ensure electrical safety during maintenance work within electric traction power supply systems. This document applies to all new lines and to all major revisions to existing lines for the following electric traction power supply systems: a) railways; b) guided mass transport systems such as 1) tramways, 2) elevated and underground railways, 3) mountain railways, 4) trolleybus systems 5) electric traction supplies for road vehicles, which use an overhead contact line system, and 6) magnetically levitated systems, which use a contact line system; c) material transportation systems. This document does not apply to: d) mine traction systems in underground mines, e) cranes, transportable platforms and similar transportation equipment on rails, temporary structures (e.g. exhibition structures) in so far as these are not supplied directly or via transformers from the contact line system and are not endangered by the electric traction power supply system, f) suspended cable cars, g) funicular railways. This document does not specify working rules for maintenance.