7SR224 Argus Description of Operation
List of Figures
Functional Diagram of 7SR224 Relay Showing Possible External Connections ...........8
7SR224 with 12 Function Keys and 3 + 8 LEDs in E10 Case......................................10
Logic Diagram: Voltage Controlled Overcurrent Protection .........................................22
Logic Diagram: Measured Directional Earth Fault Protection ......................................24
Logic Diagram: Measured Instantaneous Earth-fault Element.....................................24
Logic Diagram: Measured Time Delayed Earth Fault Element (51G)..........................25
Logic Diagram: SEF Time Delayed Element (51SEF) .................................................28
Logic Diagram: Negative Phase Sequence Overcurrent (46NPS)...............................31
Typical Autoreclose Sequence with 3 Instantaneous and 1 Delayed trip ....................41
Sequence Diagram: Quick Logic PU/DO Timers (Counter Reset Mode Off)...............55
List of Tables
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