Protection relays

Protection relays

Basic functions:

  • Minimum voltage relays
  • Maximum voltage relays
  • Differential voltage relays
  • Minimum current relays
  • Maximum current relays
  • Differential current relays
  • Interval voltage relays
  • Frequency protection relays
  • Phase sequence relays


  • High galvanic separation
  • No auxiliary supply needed, stand alone
  • High reliability, no maintenance due to reliable and proven electromechanical technology
  • Strong ability to withstand high overloads
  • Equipped with weld no transfer
    contacts for critical applications

For On-Board applications:

  • Traction brake monitoring relay
  • Traction overcurrent relay
  • Traction isolation breakdown relay
  • Catenary min. voltage detection relay
  • Catenary max. voltage detection relay
  • Wheel slip relay
  • Insulation breakdown relay
  • Battery monitoring relay
  • Motor/alternator monitoring relay
  • Pre-load filter detection relay
  • Ground fault detection relay

For Trackside applications:

  • Directional current detection relay (reverse current detection in power distribution)
  • Catenary voltage (1500V) detection relay
  • 3rd rail voltage detection relay
  • Substation ground fault detection relay
  • Heat tracing cable surveillance relay
  • Current overload relay (15000A)