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Phase monitoring

In 3-phase networks, all phase parameters such as phase failure, phase sequence, and asymmetry should be monitored.

Phase failure monitoring: motor protection in 3-phase networks

Phase failure monitoring  

Phase failure monitoring

If one phase of a 3-phase network fails, a connected motor draws the necessary current from the other two phases. The uneven load causes damage. If the motor continues to operate under nominal load, the windings will overheat.

Phase sequence monitoring: direction of rotation detection for conveyor belt drives

Direction of rotation detection for drives  

Direction of rotation detection for drives

If two conductors are swapped in a 3-phase network, the direction of the rotating field changes. This reversal of the direction of rotation can lead to errors and damage your system.

Phase asymmetry monitoring for motors

Phase asymmetry monitoring  

Phase asymmetry monitoring

The most frequent cause of asymmetry is uneven load distribution in the individual phases. In this case, a proportion of the energy is converted into reactive power. This means that the efficiency of the motor decreases, while the thermal load increases.

Application examples:

  • Protection against motor damage in the event of phase asymmetry or phase failure
  • Protection of personnel and systems in the event that the direction of rotation is reversed
  • Monitoring of connection voltages for mobile three-phase loads


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