This standard applies to single-phase instrument transformers of a nominal system voltage of 115 kV and above with capacitive insulation system for line-to-ground connection and for both indoor and outdoor application.
ANSI/IEEE C57.13.5:2009 history
2009ANSI/IEEE C57.13.5:2009 Standard of Performance and Test Requirements for Instrument Transformers of a Nominal System Voltage of 115 kV and Above