AC Protection Relays


Siemens protection concept is based on deployment of the Siprotec 4 system family, the standard for numerical protection systems. The protective devices guarantee selective and fast switch-off of faulty overhead contact lines and traction power lines and protect transformers, cables and switchgears.

These devices can also control and monitor the switching devices of the respective switchgear panel, which means fewer secondary components are required and the amount of installation and wiring work is reduced. The compact design of the devices allows them to be installed in the low-voltage compartment of the medium-voltage switchgear. 

Station control system: Our Sitras SCS-AC station control system operates with proven and globally available Simatic S7 automation components, which makes it not only universally deployable but also particularly simple to parameterize thanks to the system interfaces. The benefit to the operator is to be found in the uniform nature of the control, automation and protective equipment. It is this uniformity that enables the following tasks to be combined in the station control system:

  • Substation control

  • Process visualization and information management

  • Automated substation functions

  • Monitoring functions

  • Recording of signals

  • Systems and installation protection

The system is open for interfacing with higher-level control systems, and functions can also be conducted via a LAN or WAN.