GE MiCOM P143 Agile User Manual

7.2 Selective Logic Diagram 113
8 Timer Setting Selection 115
9 Negative Sequence Overcurrent Protection 116
9.1 Negative Sequence Overcurrent Protection Implementation 116
9.2 Non-Directional Negative Sequence Overcurrent Logic 117
9.3 Composite Earth Fault Start Logic 117
9.4 Directional Element 117
9.4.1 Directional Negative Sequence Overcurrent Logic 118
9.5 Application Notes 118
9.5.1 Setting Guidelines (Current Threshold) 118
9.5.2 Setting Guidelines (Time Delay) 119
9.5.3 Setting Guidelines (Directional element) 119
10 Earth Fault Protection 120
10.1 Earth Fault Protection Elements 120
10.2 Non-directional Earth Fault Logic 121
10.3 IDG Curve 121
10.4 Directional Element 122
10.4.1 Residual Voltage Polarisation 122
10.4.2 Negative Sequence Polarisation 123
10.5 Application Notes 124
10.5.1 Setting Guidelines (Directional Element) 124
10.5.2 Peterson Coil Earthed Systems 124
10.5.3 Setting Guidelines (Compensated networks) 128
11 Sensitive Earth Fault Protection 130
11.1 SEF Protection Implementation 130
11.2 Non-directional SEF Logic 130
11.3 SEF Any Start Logic 131
11.4 EPATR B Curve 131
11.5 Directional Element 132
11.5.1 Wattmetric Characteristic 133
11.5.2 Icos phi / Isin phi characteristic 134
11.5.3 Directional SEF Logic 135
11.6 Application Notes 136
11.6.1 Insulated Systems 136
11.6.2 Setting Guidelines (Insulated Systems) 137
12 Thermal Overload Protection 139
12.1 Single Time Constant Characteristic 139
12.2 Dual Time Constant Characteristic 139
12.3 Thermal Overload Protection Implementation 140
12.4 Thermal Overload Protection Logic 140
12.5 Application Notes 140
12.5.1 Setting Guidelines for Dual Time Constant Characteristic 140
12.5.2 Setting Guidelines for Single Time Constant Characteristic 142
13 Broken Conductor Protection 144
13.1 Broken Conductor Protection Implementation 144
13.2 Broken Conductor Protection Logic 144
13.3 Application Notes 144
13.3.1 Setting Guidelines 144
14 Blocked Overcurrent Protection 146
14.1 Blocked Overcurrent Implementation 146
14.2 Blocked Overcurrent Logic 146
14.3 Blocked Earth Fault Logic 146
14.4 Application Notes 147
14.4.1 Busbar Blocking Scheme 147
15 Second Harmonic Blocking 149
15.1 Second Harmonic Blocking Implementation 149
15.2 Second Harmonic Blocking Logic (POC Input) 150
Contents P14x
iv P14xEd1-TM-EN-1

GE MiCOM P143 Agile Specifications

General

Brand	GE
Model	MiCOM P143 Agile
Category	Control Unit
Language	English