
General settings................................................................... 169
Percentage restrained differential operation........................ 170
Negative sequence internal/external fault discriminator
feature.................................................................................. 172
Open CT detection............................................................... 173
Other additional options....................................................... 174
Low impedance restricted earth fault protection REFPDIF ........... 175
Identification.............................................................................. 175
Application.................................................................................175
Transformer winding, solidly earthed................................... 176
Transformer winding, earthed through zig-zag earthing
transformer........................................................................... 177
Autotransformer winding, solidly earthed............................. 178
Reactor winding, solidly earthed.......................................... 178
Multi-breaker applications.................................................... 179
CT earthing direction............................................................ 180
Setting guidelines...................................................................... 180
Setting and configuration......................................................180
Settings................................................................................ 181
Section 8 Impedance protection...................................................183
Full-scheme distance measuring, Mho characteristic ZMHPDIS .. 183
Identification.............................................................................. 183
Application.................................................................................183
Generator underimpedance protection application.............. 183
Setting guidelines...................................................................... 183
Configuration........................................................................ 183
Settings................................................................................ 184
High speed distance protection ZMFPDIS..................................... 187
Identification.............................................................................. 187
Application.................................................................................188
System earthing................................................................... 188
Fault infeed from remote end............................................... 191
Load encroachment..............................................................192
Short line application............................................................ 193
Long transmission line application....................................... 194
Parallel line application with mutual coupling....................... 194
Tapped line application........................................................ 200
Setting guidelines...................................................................... 203
General.................................................................................203
Setting of zone 1.................................................................. 203
Setting of overreaching zone................................................203
Setting of reverse zone........................................................ 204
Setting of zones for parallel line application......................... 205
Table of contents
4Generator protection REG670 2.2 IEC and Injection equipment REX060, REX061, REX062
Application manual