Product reliability testing for railway applications: Implementing EN50125–3

Reliability, an important design attribute, can be assessed quantitatively or qualitatively in myriad ways. For any one product such a broad gamut of testing can be narrowed by understanding the application environment, for example indoor or outdoor; the specific suitability of a particular test and if it can be done directly or indirectly; and the possible failure modes from unnecessary or excess testing. These aspects must be incorporated into any comprehensive, reasonable test plan intended for exercising and verifying product reliability for real world applications. In these situations reliability is often tied to industry standards, the requirements of which do not always translate to definitive guidelines for specific testing. In such cases the necessary testing needs to be inferred through engineering judgment and experience. In this paper we demonstrate how we employed this tack to interpret railway standard EN50125-3 in developing our internal reliability test procedure for an amplifier product to be deployed along train tracks.