Line differential protection SIPROTEC 7SD80

Line differential protection SIPROTEC 7SD80

Product Overview

Line differential protection SIPROTEC 7SD80 for selective line protection of power cables and overhead lines up to 24 km for all kind of starpoint configurations.

Features :

Fast and selective tripping is guaranteed even if the communication fails between the relays. The scope of functions includes protection functions as well as functions for control and monitoring. The interoperable connectivity to substation control systems is give by standard protocols like IEC 61850.

The general concept of redundance for protection and its communication gets completed by Ethernet redundancy protocols (PRP, HSR, RSTP) and thus increases the total system availability. Integrated functions for commissioning help and easy settings lead to short commissioning times.


  • 4 current transformers
  • 0/3 voltage transformers
  • 3/5/7 binary inputs (thresholds configurable using software)
  • 5/8 binary outputs (2 changeover)
  • 1 life contact
  • Pluggable current and voltage terminals.

Functions :

  • Differential protection, line (87L)
  • 3I0 differential protection (87N L)
  • Ground-fault differential protection for systems with resonant or isolated neutral (87Ns L)
  • Definite time-overcurrent protection with delay for phase and earth (50TD/50N TD (3 stages)
  • Inverse time-overcurrent protection (phase and ground) (51/51N)
  • Inrush current detection
  • Circuit-breaker failure protection (50BF)
  • Trip-circuit supervision (74TC)
  • Lockout (86)
  • Circuit breaker intertripping scheme (85 DT)
  • Undervoltage/overvoltage protection (27/59)
  • Underfrequency/overfrequency protection (81 U/O)
  • Directional time-overcurrent protection (phase and ground) (67/67N (3 stages))
  • Automatic reclosing (79)
  • Flexible protection functions for current, voltage, power, cos Φ, frequency
  • Thermal overload protection (49)
  • Control functions

More Information


+66 2 063 5262-3, +66 83 440 1404