CHAPTER 9: THEORY OF OPERATION FAULT LOCATORD30 LINE DISTANCE PROTECTION SYSTEM – INSTRUCTION MANUAL 9-239If the FAULT REPORT 1 VT SUBSTITUTION setting value is “I0” and the VTs are connected in a wye configuration, the faultlocation is performed based on the actual phase to ground voltages. If the VTs are connected in a delta configuration, faultlocation is performed based on the delta voltages and zero-sequence voltage approximated based on the zero-sequencecurrent:Eq. 9-20where ZSYS0 is the equivalent zero-sequence impedance behind the relay as entered under the fault report setting menu.Figure 9-10: Fault locator schemeV A13-- V AB V CA–( ) Z SYS0 I 0–=V B13-- V BC V AB–( ) Z SYS0 I 0–=V B13-- V CA V BC–( ) Z SYS0 I 0–=SETTINGSSETTINGFAULT REPORTSOURCE:SHOT # FROMAUTO RECLOSUREFAULT REPORTTRIG:I A3I_0I CI BSRC 50DD OPXVA or VABVC or VCAVB or VBC827094A5.CDROff=0ANDFAULTLOCATOR 1RUN03 SECACTUAL VALUESDATETIMEFAULT TYPEFAULT LOCATIONFAULT# RECLOSE SHOTFAULT REPORT #Vn or V_0FAULT REPORT 1 Z1MAG:FAULT REPORT 1 Z1ANGLE:FAULT REPORT 1 Z0MAG:FAULT REPORT 1 Z0ANGLE:FAULT REPORT 1LENGTH UNITS:FAULT REPORT 1LENGTH:FAULT REPORT 1 VTSUBSTITUTION:FAULT REP 1SYSTEM Z0 MAG:FAULT REP 1SYSTEM Z0 ANGLE:SETTINGS
