Siprotec 7SD61 cable differential siemens protection Relay

Product Description

Protection functions

• Differential protection for universal use with power lines and cables on all voltage levels with phase-segregated measurement (87L)

• Two line ends capability

• Suitable for transformers in protected zone (87T)

• Restricted earth-fault protection (87N) if a transformer is within the protection zone

• Well-suited for serial compensated lines

• Two independent differential stages: one stage for sensitive measuring for high resistance faults and one stage for high current faults and fast fault clearance

• Breaker-failure protection (50BF)

• Phase and earth overcurrent protection with directional element (50, 50N, 51, 51N, 67, 67N)

• Phase-selective intertripping (85)

• Overload protection (49)

• Over/undervoltage protection (59/27)

• Over/underfrequency protection (81O/U)

• Auto-reclosure single/three-pole (79)

Control functions

• Command inputs for control of CB and disconnectors (isolators)

Monitoring functions

• Self-supervision of the relay

• Trip circuit supervision (74TC)

• 8 oscillographic fault records

• CT-secondary current supervision

• Event logging / fault logging

• Switching statistics

Front design

• User-friendly local operation

• PC front port for convenient relay setting

• Function keys and 8 LEDs for local alarm

Communication interfaces

• 1 serial protection data (R2R) interface

• Front interface for PC connection

• System interface 
  

  • IEC 61850 Ethernet 
  • IEC 60870-5-103 protocol 
  • PROFIBUS-DP, DNP 3.0 and MODBUS

• Service / modem interface (rear)

• Time synchronization via IRIG-B, DCF77 or system interface

Features

• Browser-based commissioning tool

• Direct connection to digital communication networks