BS EN 50124-1:2017 - Railway applications. Insulation coordination. Basic requirements. Clearances and creepage distances for all electrical and electronic equipment

BS EN 50124-1:2017

Railway applications. Insulation coordination. Basic requirements. Clearances and creepage distances for all electrical and electronic equipment

Status : Current   Published : March 2017



This European Standard deals with insulation coordination in railways. It applies to equipment for use in signalling, rolling stock and fixed installations.

Insulation coordination is concerned with the selection, dimensioning and correlation of insulation both within and between items of equipment. In dimensioning insulation, electrical stresses and environmental conditions are taken into account. For the same conditions and stresses, these dimensions are the same.

An objective of insulation coordination is to avoid unnecessary over dimensioning of insulation.

This standard specifies:

  • requirements for clearances and creepage distances for equipment;

  • general requirements for tests pertaining to insulation coordination.

The term equipment relates to a section as defined in 3.3 it may apply to a system, a sub-system, an apparatus, a part of an apparatus, or a physical realization of an equipotential line.

This standard does not deal with:

  • distances through solid or liquid insulation;

  • distances through gases other than air;

  • distances through air not at atmospheric pressure;

  • equipment used under extreme conditions.

Product standards should align with this generic standard.

However, they may require, with justification, different requirements due to safety and/or reliability reasons, e.g. for signalling, and/or particular operating conditions of the equipment itself, e.g. overhead contact lines which should comply with EN 50119.

This standard also gives provisions for dielectric tests (type tests or routine tests) on equipment (see Annex B).


For safety critical systems, specific requirements are needed. These requirements are given in the product specific signalling standard EN 50129.

Standard NumberBS EN 50124-1:2017
TitleRailway applications. Insulation coordination. Basic requirements. Clearances and creepage distances for all electrical and electronic equipment
Publication Date31 March 2017
Normative References(Required to achieve compliance to this standard)BS EN IEC 60112:2020, IEC 60112:2020, EN IEC 60112:2020, IEC 60071-1, EN 60587, EN 60060-1, IEC 60060-1, EN 50123, EN 50163, IEC 60587, EN 60071-1, EN 60664-1:2007, IEC 60664-1:2007
Informative References(Provided for Information)EN 60383-1, IEC 61109, EN 60099-1, IEC 60664-5, EN 61936-1, EN 60947-1, EN 60099-4, IEC 60664-2-1, 2008/57/EC, EN 60507, IEC 60664-3, EN 60529, EN 60383-2, IEC 60383-1, IEC 60099-1, IEC 61558, EN 60664-5, IEC 60168, IEC/TR 60815:1986, IEC 61245, EN 50153, EN 50152, IEC 60507, IEC 60077-1, EN 61558, IEC/TS 60815, EN 60660, IEC 61936-1, IEC 60529, EN 50121, EN 60077-1, IEC 60364, EN 60364, EN 50125, BS EN 50129:2018, EN 50129:2018, EN 60664-3:2017, EN IEC 60071-2:2018, BS EN IEC 60071-2:2018, EN 62271-1:2017, IEC 62271-1:2017, IEC 60660, BS EN 50119:2020, IEC 60071-2:2018, EN 50119:2020, EN 60168, IEC 60099-4, IEC 60947-1, EN 61109, IEC 60383-2, IEC/TR 60099-3
ReplacesBS EN 50124-1:2001+A2:2005
International RelationshipsEN 50124-1:2017
Draft Superseded By15/30298489 DC
DescriptorsElectrical equipment, Clearance distances, Electronic equipment and components, Signals, Electrical insulation, Electrical engineering, Railway equipment, Railway vehicles, Leakage paths Railway applications
Title in FrenchApplications ferroviaires. Coordination de l'isolement. Prescriptions fondamentales. Distances d'isolement dans l'air et lignes de fuite pour tout matériel électrique et électronique
Title in GermanBahnanwendungen. Isolationskoordination. Grundlegende Anforderungen. Luft- und Kriechstrecken für alle elektrischen und elektronischen Betriebsmittel
ISBN978 0 580 86076 8
File Size2.075 MB

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