Distance protection relay PCS-931S

over-voltageunder-voltageover-current

PCS-931S line differential relay integrates main and back-up protection functions, which is designed for overhead line, cables and hybrid transmission lines of various voltage levels and provides comprehensive protection and control solutions. With its flexibility and the powerful PCS-Studio configuration tool, PCS-931S offers future-oriented system solutions with high investment security and low operating costs. High-speed DPFC distance protection (21D) • Six zone phase-to-phase distance protection (21L) • Six zone phase-to-ground distance protection (21L) • DPFC current differential protection (87L) • Steady-state current differential protection (87L) • Neutral current differential protection (87L) • Pilot distance protection (85) • Pilot directional earth-fault protection (85) • Unique power swing blocking releasing logic (PSBR) • Six stages phase overcurrent protection (67P, 50/51P) • Six stages earth-fault protection (67G, 50/51G) • Two stages negative-sequence overcurrent protection (67Q, 50/51Q) • Switch-onto-fault (SOTF) logic • Two stages phase undervoltage protection (27P) • Two stages phase overvoltage protection (59P) • Two stages negative-sequence overvoltage protection (59Q) • Two stages residual overvoltage protection (59G) • Four stages overfrequency protection (81O) • Four stages underfrequency protection (81U) • Four stages frequency rate-of-change protection (81R) • Two stages reverse power protection (32R) • Two stages thermal overload protection (49P) • One stage undercurrent protection (37) • Breaker failure protection (50BF) • Flashover protection (50F) • Dead zone protection (50DZ) • Broken conductor protection (46BC)