Technical description
Table of Contents
VM259.EN007
VAMP 24h support phone +358 (0)20 753 3264
41
Table of Contents
Introduction .......................................................................... 45
Main features ................................................................... 46
Principles of numerical protection techniques .......... 47
Protection functions ............................................................. 49
Maximum number of protection stages in one
application ................................................................................ 49
List of protection functions ............................................. 49
General features of protection stages ........................ 50
Distance protection Z< ................................................... 54
Short circuit distance protection Z< (21) ............. 54
Earth-fault distance protection Ze< (21N) .......... 57
Distance protection applications ........................ 66
Line differential protection LdI> (87) ............................ 71
Overcurrent stage I> (50/51) ......................................... 73
Directional overcurrent protection I
> (46) ................................. 83
Undercurrent protection I< (37) .................................... 84
Directional earth fault protection I
> (50N/51N) ............................. 91
Zero sequence voltage protection U
Thermal overload protection T> (49) ........................... 99
Overvoltage protection U> (59) ................................. 103
Undervoltage protection U< (27) ............................... 105
Reverse power and underpower protection P< (32)
Overfrequency and underfrequency Protection f>, f<
(81H/81L).................................................................................. 110
Rate of change of frequency (ROCOF) protection
df/dt (81R) ............................................................................... 112
Synchrocheck (25) ........................................................ 117
>(51F2) .................... 121
Circuit breaker failure protection CBFP (50BF) ......... 122
Programmable stages (99) .......................................... 124
Arc fault protection (50ARC/50NARC)- optional ..... 127
Inverse time operation ................................................. 131
Standard inverse delays IEC, IEEE, IEEE2, RI ...... 133
Free parametrisation using IEC, IEEE and IEEE2
equations ........................................................................... 143
Programmable inverse time curves ................... 144
Supporting functions .......................................................... 145
Event log ......................................................................... 145
Disturbance recorder ................................................... 147
Cold load pick-up and inrush current detection ..... 152
Voltage sags and swells ............................................... 154
Voltage interruptions .................................................... 156