Identification.............................................................................. 198Application................................................................................. 198Setting guidelines...................................................................... 199Equipment protection, transformers..................................... 199Power supply quality............................................................ 199The following settings can be done for the two stepovervoltage protection.......................................................... 199Two step residual overvoltage protection ROV2PTOV ................. 201Identification.............................................................................. 201Application................................................................................. 201Setting guidelines...................................................................... 201High impedance earthed systems........................................ 202Solidly earthed systems....................................................... 202Settings for two step residual overvoltage protection...........202Section 10 Frequency protection....................................................205Underfrequency protection SAPTUF ............................................. 205Identification.............................................................................. 205Application................................................................................. 205Setting guidelines...................................................................... 205Section 11 Secondary system supervision.....................................207Current circuit supervision CCSSPVC............................................207Identification.............................................................................. 207Application................................................................................. 207Setting guidelines...................................................................... 208Fuse failure supervision FRWSPVC...............................................208Identification.............................................................................. 208Application................................................................................. 208Setting guidelines...................................................................... 209DeltaU andDeltaI detection................................................. 209Dead line detection...............................................................210Sudden current and voltage change..........................................210Section 12 Control..........................................................................211Synchrocheck, energizing check, and synchronizing SESRSYN...211Identification.............................................................................. 211Application................................................................................. 211Synchronizing.......................................................................211Synchrocheck.......................................................................213Energizing check.................................................................. 215External fuse failure..............................................................216Application examples.................................................................217Single circuit breaker with single busbar.............................. 218Table of contentsRailway application RER670 2.2 IEC 5Application manual
