IEC 62505-3-1:2020 is applicable to new low voltage devices for measurement, control and protection which are: – for indoor or outdoor fixed installations in traction systems, and – operated in conjunction with high voltage equipment with an AC line voltage and frequency as specified in IEC 60850. This document also applies to measurement, control and protective devices other than low voltage devices and not covered by a specific railway product standard as far as reasonably possible. Requirements of this document prevail. This second edition cancels and replaces the first edition published in 2009. This edition includes the following significant technical changes with respect to the previous edition: – distinguish between requirements and application guides – include requirements on devices for example control and protection relays not included before; – remove parts already included in other standards, for example EN 50633 for protection principles, which is intended to become an IEC standard.

IEC 62505-3-1:2020 -