CYG PRS-7367 - Page 14

Table of contents
6 PRS-7367
3.21 Frequency gradient protection 81R .......................................................... 111
3.21.1 81R Overview................................................................................................................. 111
3.21.2 81R Protection Principle ................................................................................................ 111
3.21.3 81R Application Scope ................................................................................................... 112
3.21.4 81R Settings................................................................................................................... 113
3.22 Automatic Reclose 79AR ........................................................................... 113
3.22.1 Overview ........................................................................................................................ 113
3.22.2 Operation Principle ........................................................................................................ 115
3.22.3 Settings ..........................................................................................................................126
3.23 Synchronism check 25SYN ....................................................................... 127
3.23.1 Overview ........................................................................................................................127
3.23.2 Operation Principle ........................................................................................................129
3.23.3 Logic ...............................................................................................................................130
3.23.4 Settings ..........................................................................................................................132
3.24 Current unbalance protection 51NA ......................................................... 133
3.24.1 51NA Overview ..............................................................................................................133
3.24.2 51NA Protection Principle ..............................................................................................134
3.24.3 51NA Application Scope ................................................................................................136
3.24.4 51NA Settings ................................................................................................................136
3.25 Three phase current unbalance protection 51NT .................................... 137
3.25.1 51NT Overview ..............................................................................................................137
3.25.2 51NT Protection Principle ..............................................................................................138
3.25.3 51NT Application Scope .................................................................................................140
3.25.4 51NT Settings ................................................................................................................141
3.26 Voltage unbalance protection 59NA ......................................................... 141
3.26.1 59NA Overview ..............................................................................................................141
3.26.2 59NA Protection Principle ..............................................................................................142
3.26.3 59NA Application Scope ................................................................................................144
3.26.4 59NA Settings ................................................................................................................144
3.27 Three phase voltage unbalance protection 59NT ................................... 145