The EN 50123 series specifies requirements for d.c. switchgear and controlgear and is intended to be used in fixed electrical installations with nominal voltage not exceeding 3 000 V d.c, which supply electrical power to vehicles for public guided transport, i.e. railway vehicles, tramway vehicles, underground vehicles and trolley-buses.
Part 1 specifies general requirements.
The other parts are covering
Part 2 D.C. circuit breakers,
Part 3 Indoor d.c. disconnectors, switch-disconnectors and earthing switches,
Part 4 Outdoor d.c. disconnectors, switch-disconnectors and earthing switches,
Part 5 Surge arresters and low voltage limiters for specific use in d.c. systems,
Part 6 D.C. switchgear assemblies,
Part 7-1 Measurement, control and protection devices for specific use in d.c. traction systems -Application guide,
Part 7-2 Measurement, control and protection devices for specific use in d.c. traction systems -Isolating current transducers and other current measuring devices,
Part 7-3 Measurement, control and protection devices for specific use in d.c. traction systems -Isolating voltage transducers and other voltage measuring devices
BS EN 50123-1:2003 history
2003BS EN 50123-1:2003 Railway applications. Fixed installations. D.C. switchgear. General
1996BS EN 50123-1:1996 Railway applications - Fixed installations - d.c. switchgear - General