Functions
l Breaker failure protection. (50BF)
l Two-zone overcurrent protection for energizing a bus or a line (50E)
l Overcurrent protection of dead zone faults. (50D)
l Pole discrepancy function.
l Re-tripping after other protection tripping.
l Synchronism check. (25)
l Single pole and three pole auto-reclosing. (79)
l Circuit breaker monitoring.
l VT pole open detection logic.
l Line voltage failure supervision.
l Operating circuit supervision.
l Auto adjustment of voltage and current drift.
l Self diagnostic test.
l GPS clock synchronization.
l Fault Recorder.
l 256 event reports.
l High resolution oscillography of last 24 oscillograms.
(Compatible with international COMTRADE format)
l Rear communication ports: Ethernet with IEC 61850 or 2 RS-485 with IEC 60870-5-103 protocol,
1 RS-485 with clock synchronization, 1 RS-232 or RS-485 with printer.
l Front communication port: 1 RS-232 for testing and setting.
Features
l Overcurrent protection is provided in the relay for energizing a faulty bus or energizing a faulty line.
l The overcurrent element for dead zone protection in RCS-921 can clear the fault between breaker and CT.
l The relay will selectively re-trip when the phase current is larger than setting after other protection tripping.
l The patented adaptive floating threshold method is adopted, which is insensitive to system unbalance and disturbance. The measuring element can get both high security and high speed simultaneously.
l Innovative technology to prevent any undesired trip caused by any component failure is adopted. The relay has two independent data acquisition paths, one for a fault detector and the other for protection and its logic. Tripping outputs are supervised by the fault detector to prevent a mal-operation.
l The connector type can be selected as connectorized wiring connector and crimp terminal connector. The unique connectorized wiring connectors from the relay rear panel to the terminal blocks on the rack or cabinet makes the on-site commissioning and replacement much easier than when you do the commissioning using the traditional screw terminals on the rear panel.
l On the premise of 24 samples per cycle, all data measurement, calculation and logic discrimination could be done within one sampling period. The event recording and protection logic calculation are completed simultaneously.
l The relay provides GPS clock synchronization, including second pulse, minute pulse and IRIG-B synchronization.
l The format of event report is compatible with international COMTRADE file.
l The relay is compatible with multiple protocols- IEC61850 and IEC 60870-5-103. It provides networking interface such as RS485, RS232 and Ethernet port.