Table Of Contents; Contents - Siemens 7SR224 Description & Operation

C
ONTENTS
Documentation Set.................................................................................................................................1
Document Release History....................................................................................................................2
Software Revision History.....................................................................................................................2
Contents ..................................................................................................................................................3
List of Figures.........................................................................................................................................5
List of Tables ..........................................................................................................................................6
Section 1: Introduction ..........................................................................................................................7
1.1 Current Transformer Circuits ....................................................................................................7
1.2 External Resistors.....................................................................................................................7
1.3 Fibre Optic Communication ......................................................................................................7
1.4 Front Cover ...............................................................................................................................7
1.5 Front Fascia ..............................................................................................................................7
Section 2: Hardware Description ........................................................................................................10
2.1 General ...................................................................................................................................10
2.2 Case........................................................................................................................................10
2.3 Front Cover .............................................................................................................................11
2.4 Power Supply Unit (PSU)........................................................................................................11
2.5 Operator Interface/ Fascia ......................................................................................................11
2.6 Current Inputs .........................................................................................................................13
2.7 Voltage Inputs .........................................................................................................................13
2.8 Binary Inputs ...........................................................................................................................14
2.9 Binary Outputs (Output Relays) ..............................................................................................15
2.10 Virtual Input/Outputs ...............................................................................................................16
2.11 Self Monitoring Of The Controller ...........................................................................................16
2.11.1 Protection Healthy/Defective......................................................................................16
2.12 Battery And Capacitor Test Facility Of The Recloser .............................................................17
Section 3: Protection Functions .........................................................................................................18
3.1 Current Protection: Phase Overcurrent (67, 51, 50) ...............................................................18
3.1.1 Directional Control of Overcurrent Protection (67).....................................................18
3.1.2 Instantaneous Overcurrent Protection (50)................................................................20
3.1.3 Time Delayed Overcurrent Protection (51) ................................................................21
3.2 Current Protection: Voltage Controlled Overcurrent (51V) .....................................................23
3.3 Current Protection: Measured Earth Fault (67G, 51G, 50G) ..................................................24
3.3.1 Directional Control of Measured Earth Fault Protection (67G) ..................................24
3.3.2 Instantaneous Measured Earth Fault Protection (50G) .............................................25
3.3.3 Time Delayed Measured Earth Fault Protection (51G)..............................................26
3.4 Current Protection: Sensitive Earth Fault (67SEF, 51SEF, 50SEF).......................................27
3.4.1 Directional Control of Sensitive Earth Fault Protection (67SEF) ...............................27
3.4.2 Instantaneous Sensitive Earth Fault Protection (50SEF) ..........................................28
3.4.3 Time Delayed Sensitive Earth Fault Protection (51SEF)...........................................29
3.5 Current Protection: High Impedance Restricted Earth Fault (64H) ........................................30
3.6 Current Protection: Cold Load (51c) .......................................................................................31
3.7 Current Protection: Negative Phase Sequence Overcurrent (46NPS) ...................................32
3.8 Current Protection: Under-Current (37) ..................................................................................33
3.9 Current Protection: Thermal Overload (49) ............................................................................34
3.10 Voltage Protection: Phase Under/Over Voltage (27/59).........................................................36
©2009 Siemens Protection Devices Limited
(1) Description of Operation 7SR224
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