Apply the SEL-321 Relay for primary and/or backup single-or three-pole trip transmission line protection,including series-compensated lines.
Use the advanced single-pole tripping logic with phase selection, open-pole interval protection,and phase discordance logic with three-pole trip to protect against excessive single-pole-open events.
Choose from among the many communications-assisted tripping schemes available (POTT, DCUB, DCB, PUTT, DUTT, and DTT) including unique Mirrored Bits communications.
Select the load-encroachment feature to prevent operation of three-phase elements under high load conditions.
Use the time-overcurrent elements to provide current-dependent, time-delayed fault detection along the protected line and backup protection for remote terminals.
Use weak-infeed logic to rapidly clear both line terminals for internal faults near the weak terminal.
Select the SEL-321-5 Relay for enhanced performance on 50 Hz systems, including single-pole tripping.
Use SEL-5040 Power System Report Manager Software to automatically gather relay event reports on your PC and manage them with a database.
Use SEL-5010 Relay Assistant Software to manage your relay settings.
Use SEL-5601 Analytic Assistant Software to display oscillograms and vector diagrams to analyze event reports.