SIPROTEC 4 7SJ63 Multifunction Protection Relay - Siemens

5 Overcurrent Protection / 7SJ63Application5The SIPROTEC 4 7SJ63 unit is a numericalprotection relay that also performs controland monitoring functions and therefore supportsthe user in cost-effective power systemmanagement, and ensures reliable supply ofelectric power to the customers. Local operationhas been designed according to ergonomiccriteria. A large, easy-to-read graphicdisplay was a major design aim.ControlThe integrated control function permits controlof disconnect devices (electrically operated/motorizedswitches) or circuit-breakersvia the integrated operator panel, binary inputs,DIGSI 4 or the control and protectionsystem (e.g. SICAM). The present status (orposition) of the primary equipment can bedisplayed. 7SJ63 supports substations withsingle and duplicate busbars. The number ofelements that can be controlled (usually 1 to5) is only restricted by the number of inputsand outputs available. A full range of commandprocessing functions is provided.Programmable logicThe integrated logic characteristics (CFC)allow the user to implement their own functionsfor automation of switchgear (interlocking)or a substation via a graphic userinterface. The user can also generate userdefinedmessages.5/118Line protectionThe 7SJ63 units can be used for line protectionof high and medium-voltage networkswith earthed (grounded), low-resistanceearthed, isolated or compensated neutralpoint.Motor protectionWhen protecting motors, the 7SJ63 relays aresuitable for asynchronous machines of allsizes.Transformer protectionThe 7SJ63 units perform all functions ofbackup protection supplementary to transformerdifferential protection. The inrushsuppression effectively prevents tripping byinrush currents.The high-impedance restricted earth-faultprotection detects short-circuits and insulationfaults on the transformer.Backup protectionThe relays can be used universally for backupprotection.Metering valuesExtensive measured values, limit values andmetering values permit improved systemsmanagement.Fig. 5/105 Function diagramSiemens SIP · 2006