Gives mathematical expressions for reliability, availability, maintainability and maintenance support measures defined in IEC 60050-191. The following classes of items are considered separately in this standard: - non-repaired items; - repaired items with zero time to restoration; - repaired items with non-zero time to restoration. In order to keep the mathematical formulae as simple as possible, the following basic mathematical models are used to quantify dependability measures: - random variable (time to failure) for non-repaired items; - simple (ordinary) renewal process for repaired items with zero time to restoration; - simple (ordinary) alternating renewal process for repaired items with non-zero time to restoration.

00/402267 DC : DRAFT MARCH 2000

BS EN 61703 : 2016

IEC 61703 : 2.0 - Identical