ABB RELION 620 Series Technical Manual page 19

620 series ANSI
Technical Manual
Functionality............................................................................... 389
Operation principle..................................................................... 389
Application.................................................................................. 398
Signals........................................................................................402
Settings.......................................................................................403
Monitored data............................................................................404
Technical data............................................................................ 404
Differential protection............................................................................404
Motor differential protection 87M..................................................... 404
Identification............................................................................... 404
Function block............................................................................ 405
Functionality............................................................................... 405
Operation principle..................................................................... 405
Application.................................................................................. 411
Signals........................................................................................419
Settings.......................................................................................419
Monitored data............................................................................420
Technical data............................................................................ 421
Stabilized and instantaneous differential protection for 3W
transformers 87T............................................................................. 421
Identification............................................................................... 421
Function block............................................................................ 422
Functionality............................................................................... 422
Operation principle..................................................................... 422
CT connections and transformation ratio correction...................436
Application.................................................................................. 438
Recommendations for current transformers............................... 446
Signals........................................................................................450
Settings.......................................................................................451
Monitored data............................................................................453
Technical data............................................................................ 456
Numerical stabilized low impedance restricted earth-fault
protection 87L0ZREF...................................................................... 456
Identification............................................................................... 456
Function block............................................................................ 456
Functionality............................................................................... 456
Operation principle..................................................................... 457
Application.................................................................................. 461
Signals........................................................................................465
Settings.......................................................................................465
Table of contents
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