10.4.3 Functionality...................................................................................................................... 1848
10.4.4 Analog channel configuration........................................................................................ 1849
10.4.5 Operation principle.......................................................................................................... 1849
10.4.6 Application......................................................................................................................... 1854
10.4.7 Signals.................................................................................................................................1854
10.4.8 VSQVUB Settings...............................................................................................................1855
10.4.9 VSQVUB Monitored data................................................................................................. 1856
10.4.10 Technical data ................................................................................................................... 1857
11 General function block features........................................................1858
11.1 Definite time characteristics.......................................................................................................... 1858
11.1.1 Definite time operation................................................................................................... 1858
11.2 Current based inverse definite minimum time characteristics............................................... 1862
11.2.1 IDMT curves for overcurrent protection.......................................................................1862
11.2.2 Reset in inverse-time modes.......................................................................................... 1885
11.2.3 Inverse-timer freezing......................................................................................................1895
11.3 Voltage based inverse definite minimum time characteristics...............................................1895
11.3.1 IDMT curves for overvoltage protection...................................................................... 1895
11.3.2 IDMT curves for undervoltage protection....................................................................1902
11.4 Frequency measurement and protection ....................................................................................1906
11.5 Frequency adaptivity and generator start-up protection.........................................................1907
11.6 Measurement modes....................................................................................................................... 1908
11.7 Calculated measurements...............................................................................................................1910
11.8 Test mode............................................................................................................................................1911
11.8.1 Functionality.......................................................................................................................1912
11.8.2 Application configuration and Test mode....................................................................1912
11.8.3 Control mode......................................................................................................................1913
11.8.4 Application configuration and Control mode.............................................................. 1913
11.8.5 Authorization......................................................................................................................1913
11.8.6 LHMI indications................................................................................................................1914
12 Requirements for measurement transformers................................1915
12.1 Current transformers........................................................................................................................1915
12.1.1 Current transformer requirements for overcurrent protection............................... 1915
12.1.2 Current transformer requirements for transformer differential protection.........1918
13 Protection relay's physical connections........................................... 1922
13.1 Module diagrams...............................................................................................................................1922
13.2 Communication modules.................................................................................................................1936
13.3 Arc sensor interface.......................................................................................................................... 1938
Contents
28 REX640
Technical Manual