BS EN 61703:2016 - Mathematical expressions for reliability, availability, maintainability and maintenance support terms
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BS EN 61703:2016

Mathematical expressions for reliability, availability, maintainability and maintenance support terms

Status : Current, Under review   Published : December 2016



IEC 61703:2016 provides mathematical expressions for selected reliability, availability, maintainability and maintenance support measures defined in IEC 60050­192:2015. In addition, it introduces some terms not covered in IEC 60050-192:2015. They are related to aspects of the system of item classes (see hereafter). According to IEC 60050-192:2015, dependability [192-01-22] is the ability of an item to perform as and when required and an item [192-01-01] can be an individual part, component, device, functional unit, equipment, subsystem, or system. To account for mathematical constraints, this standard splits the items between the individual items considered as a whole (e.g. individual components) and the systems made of several individual items. It provides general considerations for the mathematical expressions for systems as well as individual items but the individual items which are easier to model are analysed in more detail with regards to their repair aspects. This standard is mainly applicable to hardware dependability, but many terms and their definitions may be applied to items containing software. This second edition cancels and replaces the first edition published in 2001. This edition constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition:

- standard made as self containing as possible;

- item split between individual items and systems;

- generalization of the dependability concepts for systems made of several components [introduction of the conditional failure intensity (Vesely failure rate);

- introduction of the state-transition and the Markovian models;

- generalization of the availability to production availability];

- introduction of curves to illustrate the various concepts. Keywords: mathematical expressions for dependability

Standard NumberBS EN 61703:2016
TitleMathematical expressions for reliability, availability, maintainability and maintenance support terms
StatusCurrent, Under review
Publication Date31 December 2016
Normative References(Required to achieve compliance to this standard)IEC 60050-192:2015, ISO 3534-1:2006
Informative References(Provided for Information)EN 61165, EN 61078, EN 61511, IEC 61078, IEC 61165, IEC 61511, EN 61025, IEC 60605, IEC 61025, IEC 61508, EN 61508
ReplacesBS EN 61703:2002
International RelationshipsEN 61703:2016,EN 61753-021-6:2008,IEC 61703:2016
Draft Superseded By15/30281629 DC
DescriptorsReliability, Quality assurance, Mathematical calculations, Mathematics, Electrical engineering, Availability, Terminology, Mathematical symbols, Maintenance, Quality control, Maintainability
Title in FrenchExpressions mathématiques pour les termes de fiabilité, de disponibilité, de maintenabilité et de logistique de maintenance
Title in GermanMathematische Ausdrücke für Begriffe der Zuverlässigkeit, Verfügbarkeit, Instandhaltbarkeit und Instandhaltungsbereitschaft
ISBN978 0 580 82730 3
File Size3.812 MB

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