Two step overvoltage protection OV2PTOV ..................................192Identification.............................................................................. 192Application................................................................................. 193Setting guidelines...................................................................... 193Equipment protection, such as for motors, generators,reactors and transformers.................................................... 194Equipment protection, capacitors......................................... 194Power supply quality............................................................ 194High impedance earthed systems........................................ 194The following settings can be done for the two stepovervoltage protection.......................................................... 194Two step residual overvoltage protection ROV2PTOV ................. 197Identification.............................................................................. 197Application................................................................................. 197Setting guidelines...................................................................... 197Equipment protection, such as for motors, generators,reactors and transformersEquipment protection fortransformers......................................................................... 198Equipment protection, capacitors......................................... 198Power supply quality............................................................ 198High impedance earthed systems........................................ 198Direct earthed system.......................................................... 199Settings for two step residual overvoltage protection...........200Section 10 Frequency protection....................................................203Underfrequency protection SAPTUF ............................................. 203Identification.............................................................................. 203Application................................................................................. 203Setting guidelines...................................................................... 203Overfrequency protection SAPTOF ...............................................204Identification.............................................................................. 204Application................................................................................. 205Setting guidelines...................................................................... 205Rate-of-change of frequency protection SAPFRC .........................206Identification.............................................................................. 206Application................................................................................. 206Setting guidelines...................................................................... 206Section 11 Secondary system supervision.....................................209Current circuit supervision CCSSPVC............................................209Identification.............................................................................. 209Application................................................................................. 209Setting guidelines...................................................................... 209Fuse failure supervision FUFSPVC................................................210Table of contentsLine differential protection RED650 2.2 IEC 5Application manual
