Patent ID: 8248739

Claim:
An electrical switching apparatus for another apparatus including a number of insulators, a number of temperature sensors operatively associated with said number of insulators, and a number of conductors operatively associated with said number of insulators, said electrical switching apparatus comprising: a number of separable contacts; an operating mechanism structured to open and close said number of separable contacts; a number of sensors structured to sense a number of currents flowing through said number of separable contacts and through said number of conductors; a processor structured to input the sensed number of currents from said number of sensors; and an output, wherein said processor is further structured to calculate at least one of: (a) a thermal age of said another apparatus from a number of sensed temperatures from said number of temperature sensors, and (b) the thermal age of said another apparatus from said sensed number of currents, and wherein said output includes the thermal age of said another apparatus, wherein said processor is further structured to determine temperature of said another apparatus and to determine insulation life expectancy of said another apparatus from e (a+b(ln(TEMP))) , wherein a, b and e are constants, ln is the natural logarithm, and TEMP is said determined temperature.