
7.2 Out-of-step protection OOSPPAM (78)............................................................................................103
7.2.1 Identification.....................................................................................................................................103
7.2.2 Application.........................................................................................................................................103
7.2.3 Setting guidelines............................................................................................................................106
Section 8 Current protection.............................................................................................. 109
8.1 Four step phase overcurrent protection OC4PTOC(51/67).........................................................109
8.1.1 Identification.................................................................................................................................... 109
8.1.2 Application........................................................................................................................................ 109
8.1.3 Setting guidelines............................................................................................................................ 110
8.1.3.1 Settings for each step.................................................................................................................. 112
8.2 Four step residual overcurrent protection, (Zero sequence or negative sequence
directionality) EF4PTOC (51N/67N).................................................................................................. 114
8.2.1 Identification..................................................................................................................................... 114
8.2.2 Setting guidelines.............................................................................................................................115
8.2.2.1 Settings for each step (x = 1, 2, 3 and 4)................................................................................... 115
8.2.2.2 Common settings for all steps................................................................................................... 117
8.2.2.3 2nd harmonic restrain.................................................................................................................. 118
8.2.2.4 Parallel transformer inrush current logic..................................................................................119
8.2.2.5 Switch onto fault logic................................................................................................................. 119
8.3 Four step directional negative phase sequence overcurrent protection NS4PTOC (46I2)... 120
8.3.1 Identification.....................................................................................................................................120
8.3.2 Application.........................................................................................................................................120
8.3.3 Setting guidelines.............................................................................................................................122
8.3.3.1 Settings for each step .................................................................................................................122
8.3.3.2 Common settings for all steps...................................................................................................125
8.4 Sensitive directional residual overcurrent and power protection SDEPSDE (67N).................126
8.4.1 Identification.....................................................................................................................................126
8.4.2 Application.........................................................................................................................................126
8.4.3 Setting guidelines.............................................................................................................................127
8.5 Thermal overload protection, one time constant Fahrenheit/Celsius LFPTTR/
LCPTTR (26)............................................................................................................................................135
8.5.1 Identification.....................................................................................................................................136
8.5.2 Application.........................................................................................................................................136
8.5.3 Setting guideline.............................................................................................................................. 136
8.6 Directional underpower protection GUPPDUP (37)....................................................................... 137
8.6.1 Identification..................................................................................................................................... 137
8.6.2 Application.........................................................................................................................................137
8.6.3 Setting guidelines............................................................................................................................ 139
8.7 Directional overpower protection GOPPDOP (32)......................................................................... 143
8.7.1 Identification.....................................................................................................................................143
8.7.2 Application.........................................................................................................................................143
8.7.3 Setting guidelines............................................................................................................................ 145
Table of contents
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Application manual