PSC 113.0602(8)(8) “Electric distribution line” means circuits operating at less than 50,000 volts. PSC 113.0602(9)(9) “Forced outage” means an outage which cannot be deferred. PSC 113.0602(10)(10) “Major catastrophic events” means train wrecks, plane crashes, or explosions that are beyond the utility’s control and result in widespread system damages causing customer interruptions that affect at least ten percent of the customers in the system or in an operating area and/or result in customers being without electric service for durations of at least 24 hours. PSC 113.0602(11)(11) “Major storm” means a period of severe adverse weather resulting in widespread system damage causing customer interruptions that affect at least ten percent of the customers on the system or in an operating area and/or result in customers being without electric service for durations of at least 24 hours. PSC 113.0602(12)(12) “Momentary interruption” means an interruption of electric service with a duration shorter than the time necessary to be classified as a customer interruption. PSC 113.0602(13)(13) “Operating area” means a geographical sub-division of each electric utility’s service territory that functions under the direction of a company office and may be used for interruption reporting under this part. These areas may also be referred to as regions, divisions, or districts. PSC 113.0602(14)(14) “Outage” means the failure of a power system component that results in one or more customer interruptions. PSC 113.0602(15)(15) “Outage duration” (reported in minutes) means the one minute or greater period from the initiation of an interruption to a customer until service has been restored to that customer. PSC 113.0602(16)(16) “Partial circuit outage customer count” means where only part of a circuit experiences an outage, the number of customers affected is estimated, unless an actual count is available. When power is partially restored, the number of customers restored is also estimated. Most utilities use estimates based on the portion of the circuit restored. PSC 113.0602(17)(17) “Planned outages” means those outages which the utility schedules. When customer service interruptions are necessary, the utility should notify affected customers in advance. These interruptions are sometimes necessary to connect new customers or perform maintenance activities safely. They shall not be included in the calculation of reliability indices. PSC 113.0602 NoteNote: Also see s. PSC 113.0502, Planned service interruptions. PSC 113.0602(18)(18) “Police actions” means request or order of police or fire officials to interrupt service due to an emergency. PSC 113.0602(19)(19) “Reliability” means the degree to which electric service is supplied without interruption. PSC 113.0602(20)(20) “Reliability indexes” include the following performance indices for measuring frequency and duration of service interruptions that have been developed by the Edison Electric Institute (EEI), the Institute of Electrical and Electronics Engineers (IEEE), the Canadian Electric Association (CEA) and the American Public Power Association (APPA). They are recognized as standard definitions for the electric utility industry and may be applied to entire distribution systems, operating areas, sub-operating areas or individual circuits. Customer interruptions attributed to major storms, major catastrophic events, or police actions, as defined herein, shall be included in the calculation of these indices throughout this standard. PSC 113.0602(20)(a)(a) System Average Interruption Frequency Index (SAIFI). The SAIFI index is the average number of interruptions per customer during a year. It is determined by dividing the total annual number of customer interruptions by the average number of customers served during the year. SAIFI = total number of customer interruptions
average number of customers served
PSC 113.0602(20)(b)(b) System Average Interruption Duration Index (SAIDI). The SAIDI index is the average customer-minutes of interruption per customer. It is determined by dividing the annual sum of customer-minutes of interruption by the average number of customers served during the year. SAIDI = sum of customer-minutes of interruption
average number of customers served
PSC 113.0602(20)(c)(c) Customer Average Interruption Duration Index (CAIDI). The CAIDI index is the average customer-minutes of interruption per customer interruption. It approximates the average length of time required to complete service restoration. It is determined by dividing the annual sum of all customer-minutes of interruption durations by the annual number of customer interruptions. CAIDI = sum of customer-minutes of interruption
total number of customer interruptions
PSC 113.0602 HistoryHistory: Cr. Register, July, 2000, No. 535, eff. 8-1-00; CR 02-027: am. (8), Register December 2002 No. 564, eff. 1-1-03. PSC 113.0603(1)(1) Aggregate system reliability performance. Each electric utility with 100,000 customers or more shall keep a record of the necessary interruption data and calculate the SAIFI, SAIDI and CAIDI indices of its system and of each operating area, if applicable, at the end of each calendar year for the previous 12-month period. PSC 113.0603(2)(2) Individual circuit reliability performance. Each utility also shall, at the end of each calendar year, calculate the SAIFI, SAIDI and CAIDI indices for each circuit in each operating area. Each circuit in each operating area shall then be listed in order separately according to its SAIFI index, its SAIDI index and also its CAIDI index, beginning with the highest values for each index. PSC 113.0603(3)(3) Utilities shall maintain as much information as feasible on momentary outages. Each utility shall keep an annual count of recloser operations, or equivalent information through application of monitoring technology. PSC 113.0603 HistoryHistory: Cr. Register, July, 2000, No. 535, eff. 8-1-00.