European Committee for Electrotechnical Standardization

Railway applications - Communication, signalling and processing systems - Software for railway control and protection systems - Incorporating corrigendum February 2014
 N EN 50128

Annotation

This European Standard specifies the process and technical requirements for the development of software for programmable electronic systems for use in railway control and protection applications. It is aimed at use in any area where there are safety implications. These systems can be implemented using dedicated microprocessors, programmable logic controllers, multiprocessor distributed systems, larger scale central processor systems or other architectures.

This European Standard is applicable exclusively to software and the interaction between software and the system of which it is part.

This European Standard is not relevant for software that has been identified as having no impact on safety, i.e. software of which failures cannot affect any identified safety functions.

This European Standard applies to all safety related software used in railway control and protection systems, including

– application programming,

– operating systems,

– support tools,

– firmware.

Application programming comprises high level programming, low level programming and special purpose programming (for example: Programmable logic controller ladder logic).

This European Standard also addresses the use of pre-existing software and tools. Such software may be used, if the specific requirements in 7.3.4.7 and 6.5.4.16 on pre-existing software and for tools in 6.7 are fulfilled.