NOTE 1 The generated electric power and the load in an island may be any combination of customer-owned and utility-owned

a) intentional island

island that is intentionally created, usually to restore or maintain generation of electricity in to a section of the utility grid affected by a fault

NOTE 2 An intentional island includes an agreement between the controlling utility and the operators of customer-owned generation

b) unintentional island

island in which the generation of electricity within the island that is supposed to shut down continues to operate

c) run-on

amount of time that an unintentional island exists

NOTE 3 “Run-on” is defined as the interval between the start of an abnormal condition on the distribution system and the time when the distributed generator ceases to energize the distribution system

NOTE 4 The time represented by run-on is also referred to as "trip time"