Siemens SIPROTEC 4 7SD610 Line Differential Protection Relay

Description

7SD610 Relay

The SIPROTEC 7SD610 relay is a differential protection relay suitable for all types of applications and incorporates all those functions required for differential protection of lines, cables and transformers. Transformers and compensation coils within the differential protection zone are protected by means of integrated functions, which were previously to be found only in transformer differential protection. It is also well-suited for complex applications such as series and parallel compensation of lines and cables. It is designed to provide differential and directional backup protection for all voltage levels and types of networks. The relay features high-speed and phase-selective short circuit measurement. The unit is thus suitable for single-phase and three-phase fault clearance.

Functions Of Siemens Siprotec 7SD610 Relay

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 the 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 the 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

Features

  • Browser-based commissioning tool
  • Direct connection to digital communication networks

Digital data communication for differential current measurement is effected via fiberoptic cables, networks, or pilot wires connections so that the line ends can be quite far apart. The serial protection interface (R2R interface) of the relay can flexibly be adapted to the requirements of all existing communication media. If the communication method is changed, flexible retrofitting of communication modules to the existing configuration is possible. Apart from the main protection function, i.e. the differential protection, the SIPROTEC 4 7SD610 has a full range of configurable emergency and/or backup protection functions such as phase and earth overcurrent protection with directional elements if voltage transformers are connected. Overload, under and over-voltage/frequency, and breaker failure protection round off the functional scope of the SIPROTEC 7SD610.