IEVref: 692-08-05 ID: Language: en Status: Standard Term: mean duration of a customer interruption Synonym1: customer average interruption duration index, CA US [Preferred] Synonym2: CAIDI [Admitted] Synonym3: Symbol: TI Definition: sum of durations of all supply interruptions to individual customers during a time interval, divided by the number of these supply interruptionsNote 1 to entry: If tij is the duration of the ith interruption of supply to customer j and nj is the number of times customer j is affected during a time interval of duration T, then the mean duration of a customer interruption is given by${T}_{\text{I}}=\frac{{\sum }_{i}{\sum }_{j}{t}_{ij}}{{\sum }_{j}{n}_{j}}$ Note 2 to entry: Only sustained interruptions are considered. Note 3 to entry: The term "customer" represents the end user and not some intermediate distribution system or company. Note 4 to entry: Mean duration of a customer interruption can be used to describe past performance or to estimate expected future performance. Note 5 to entry: This measure is also equal to service unavailability per customer served divided by interruption frequency per customer served. Note 6 to entry: This entry was numbered 191-27-05 in IEC 60050-191:1990. Publication date: 2017-12-15 Source: Replaces: Internal notes: CO remarks: TC/SC remarks: VT remarks: Domain1: Domain2: Domain3: Domain4: Domain5: