Siemens Siprotec 4 Siprotec 7SD610 Universal Differential Protection Relay

The Siprotec 7SD610 Protection Relay is a differential protection relay suitable for all types of applications and incorporating 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.Digital data communication for differential current measurement is effected via fiber-optic 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 7SD610 has a full range of configurable emergency and/or backup protection functions such as phase and earth over current 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 7SD610.

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 relay and protection data (R2R) communication
• 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 relay setting
• Function keys and 14 LEDs f. 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

SIPROTEC 4 leads the way in integrating protection, control, measurement, and automation functions in one device. The homogenous system platform, the unique DIGSI 4 engineering program, and extensive experience of more than a million successfully operating devices in the field worldwide – thanks to these unique advantages, SIPROTEC 4 enjoys top recognition among users worldwide. SIPROTEC 4 is the industry standard for digital protection technology today in all fields of application.