Function overview

• Differential protection for two-winding transformers (3-/1-phase)
• Differential protection for motors and generators
• Differential protection for short lines
• Differential protection for busbars up to 7 feeders (phase-segregated or with summation CT)

Protection functions

• Differential protection with phase-segregated measurement
• Sensitive measuring stage for low-fault currents
• Fast tripping for high-fault currents
• Restraint against inrush of the transformer
• Phase/ground-overcurrent protection
• Overload protection with or without temperature measurement
• Negative-sequence protection
• Breaker failure protection
• Low-or high-impedance restricted earth fault (REF)

Control functions

• Commands for control of c.b. and isolators
• Control via keyboard, binary inputs, DIGSI 4 or SCADA system
• User-defined logic with CFC

Monitoring functions

• Self-supervision of the relay
• Trip circuit supervision
• Oscillographic fault recording
• Permanent differential and restraint current measurement, extensive scope of operational values

Communication interfaces

• PC front port for setting with DIGSI 4
• System interface IEC 61850 Ethernet
  • IEC 60870-5-103 protocol
  • PROFIBUS-FMS
  • PROFIBUS-DP
  • MODBUS
  • DNP 3.0
  • Service interface for DIGSI 4 (modem)/temperature monitoring (thermo-box)
  • Time synchronization via IRIG-B/DCF 77