Siemens SIPROTEC 7SJ62 Instruction Manual page 10

6.6 Sensitive Ground Fault Detection (64, 50Ns, 67Ns).......................................................... 6-73
6.6.1 Description of Sensitive Ground Fault Detection ............................................................... 6-73
6.6.1.1 Voltage Element ................................................................................................................ 6-73
6.6.1.2 Current Elements............................................................................................................... 6-74
6.6.1.3 Determination of Direction ................................................................................................. 6-74
6.6.1.4 Location of Ground Connections ....................................................................................... 6-78
6.6.2 Programming Settings ....................................................................................................... 6-79
6.6.2.1 Settings for Sensitive Ground Fault Detection................................................................... 6-83
6.6.2.2 Information List for Sensitive Ground Fault Detection ....................................................... 6-85
6.7 Negative Sequence Protection (46)................................................................................... 6-86
6.7.1 Description of Negative Sequence Protection ................................................................... 6-86
6.7.1.1 Determination of Unbalanced Load ................................................................................... 6-86
6.7.1.2 Definite Time Elements (46-1, 46-2).................................................................................. 6-86
6.7.1.3 Inverse Time Element (46-TOC)........................................................................................ 6-87
6.7.2 Programming Settings ....................................................................................................... 6-89
6.7.2.1 Settings for Negative Sequence (Phase Balance) Current Protection .............................. 6-91
6.7.2.2 Information List for Negative Sequence Current Protection .............................................. 6-93
6.8 Motor Starting Protection (48)............................................................................................ 6-94
6.8.1 Description of Motor Starting Protection ............................................................................ 6-94
6.8.2 Programming Settings ....................................................................................................... 6-96
6.8.2.1 Settings for Motor Starting Time Monitoring ...................................................................... 6-97
6.8.2.2 Information List for Motor Starting Time Monitoring........................................................... 6-98
6.9 Thermal Overload Protection (49) ..................................................................................... 6-99
6.9.1 Description of Thermal Overload Protection...................................................................... 6-99
6.9.2 Programming Settings ..................................................................................................... 6-101
6.9.2.1 Settings for Thermal Overload Protection........................................................................ 6-104
6.9.2.2 Information List for Thermal Overload Protection ............................................................ 6-105
6.10 Start Inhibit for Motors (66/68) ......................................................................................... 6-106
6.10.1 Description of Start Inhibit for Motors .............................................................................. 6-106
6.10.2 Programming Settings ..................................................................................................... 6-108
6.10.2.1 Settings for Start Inhibit of Motors ................................................................................... 6-109
6.10.2.2 Information List for Start Inhibit of Motors........................................................................ 6-110
6.11 Voltage Protection (27, 59) .............................................................................................. 6-111
6.11.1 Description of Voltage Protection .................................................................................... 6-111
6.11.1.1 Measurement Principle .................................................................................................... 6-111
6.11.1.2 Overvoltage Protection (59)............................................................................................. 6-111
6.11.1.3 Undervoltage Protection (27)........................................................................................... 6-112
6.11.2 Programming Settings ..................................................................................................... 6-115
6.11.2.1 Overvoltage Protection .................................................................................................... 6-116
6.11.2.2 Settings for Overvoltage Protection ................................................................................ 6-116
6.11.2.3 Information List for Overvoltage Protection ..................................................................... 6-116
6.11.2.4 Undervoltage Protection .................................................................................................. 6-117
6.11.2.5 Settings for Undervoltage Protection ............................................................................... 6-118
6.11.2.6 Information List for Undervoltage Protection ................................................................... 6-119
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7SJ62 Instruction Manual
C53000-G1140-C121-1