Solutions   for   Protecting   andManaging   the   Electrical   Network

STS   7041

Check synchronizing relay

The STS 7041 is a relay which verifies the synchronism between two sources. It is generally used to allow a closing signal to be trasmitted to a breaker which ties together two independent sources.
The relay is supplied in a modular plug-in case type R3, which may be mounted either as a separate relay, projecting or flush mounting, or as an element in a standard 19" rack cradle.
The STS 7041 is based on the analysis of signals by analogue and numerical systems granting it high precision and stability.


  • Synchro Check [25]


  • Settings by frontal switches / potentiometers
  • Setting ranges by switches:
    – voltage difference: ±3, 5, 10, 20, 30% Un
    – frequency difference: ±0.16, 0.08, 0.04, 0.02, 0.01% Hz
    – phase-angle difference: ±10, 20, 40 °
  • LED indication for each major function, with one LED flashing at slip frequency
  • Operating at 50 or 60 Hz
  • Auxiliary output relay with two high-power contacts
  • Security achieved by internal redundancy


  Device Doc Type Lang. Ref. Index
STS 7041 Leaflet EN / FR FA850 A
STS 7041 User Manual EN M.1748 B
STS 7041 Connection/Definition Diagram EN / FR 9848 D