Function Application 1 Application 2Directional over-power protection GOPPDOP(32)Application dependent Application dependentNegative sequence based overcurrentprotection DNSPTOC (46)Application dependent Application dependentTwo step undervoltage protection UV2PTUV(27)Application dependent Application dependentTwo step overvoltage protection OV2PTOV(59)Application dependent Application dependentTwo step residual overvoltage protectionROV2PTOV (59N)Disabled EnabledUnder frequency protection SAPTUF (81)(instance 1)Application dependent Application dependentUnder frequency protection SAPTUF (81)(instance 2)Application dependent Application dependentOver frequency protection SAPTOF (81)(instance 1)Application dependent Application dependentOver frequency protection SAPTOF (81)(instance 2)Application dependent Application dependentRate-of-change of frequency protectionSAPFRC (81) (instance 1)Application dependent Application dependentRate-of-change of frequency protectionSAPFRC (81) (instance 2)Application dependent Application dependentCurrent circuit supervision CCSRDIF (87) Enabled EnabledFuse failure supervision SDDRFUF Enabled EnabledBreaker close/trip circuit monitoringTCSSCBREnabled EnabledSynchrocheck, energizing check, andsynchronizing SESRSYN (25)Application dependent Application dependentAutorecloser SMBRREC (79) Enabled Enabled2.3.4 Bus coupler in a solidly grounded networkNormally the following fault scenarios require back-up protection functions:• Short circuits on one of the busbar sections and short circuits on outgoing lines. Forthese faults the four step phase overcurrent protection should be used. The four stepphase overcurrent protection has the possibility of directional function as well asdifferent time delay characteristics. It is important to base the setting on faultcalculations considering different operational states as well as time delaycoordination with other protections in the system.• Phase-to-ground faults one of the busbar sections and phase-to-ground faults onoutgoing lines. For these faults the four step residual overcurrent protection should beused. The four step residual overcurrent protection has the possibility of directional1MRK 511 286-UUS A Section 2Application35Application manual
