ABB RELION RET670 - Page 17

Load encroachment....................................................................509
Under voltage seal-in
..................................................................510
Section 9
Current protection..............................................................513
Instantaneous phase overcurrent protection PHPIOC (50).................. 513
Identification.................................................................................... 513
Application....................................................................................... 513
Setting guidelines............................................................................ 514
Meshed network without parallel line..........................................515
Meshed network with parallel line...............................................517
Directional phase overcurrent protection, four steps
OC4PTOC(51_67)................................................................................ 519
Identification.................................................................................... 519
Application....................................................................................... 519
Setting guidelines............................................................................ 520
Settings for each step.................................................................522
Setting example..........................................................................526
Instantaneous residual overcurrent protection EFPIOC (50N)............. 531
Identification.................................................................................... 531
Application....................................................................................... 531
Setting guidelines............................................................................ 531
Directional residual overcurrent protection, four steps EF4PTOC
(51N/67N)............................................................................................. 534
Identification.................................................................................... 534
Application....................................................................................... 535
Setting guidelines............................................................................ 537
Common settings for all steps.................................................... 537
2nd harmonic restrain.................................................................539
Parallel transformer inrush current logic.....................................539
Switch onto fault logic.................................................................540
Settings for each step (x = 1, 2, 3 and 4)................................... 541
Transformer application example............................................... 544
Four step directional negative phase sequence overcurrent
protection NS4PTOC (46I2)..................................................................549
Identification.................................................................................... 549
Application....................................................................................... 549
Setting guidelines............................................................................ 551
Settings for each step ................................................................551
Common settings for all steps.................................................... 554
Sensitive directional residual overcurrent and power protection
SDEPSDE (67N)...................................................................................555
Table of contents
Transformer protection RET670 2.2 ANSI 11
Application manual