socomec 4145 - Power Quality Monitoring Parameters; Power Quality Monitoring Table Survey

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During an Interruption the voltage sinks well below its nominal value. In 3-phase
systems, an Interruption begins when the voltages on all phases are below threshold
and ends when one phase is equal to or above the interruption threshold plus
hysteresis. The trigger conditions for interruptions are threshold and hysteresis.
Interruptions are characterized by duration, magnitude and time of occurrence. The
picture explain this:
Picture: Characteristics of a voltage interruption
Rapid voltage changes are quick transitions of the RMS voltage between two steady-
states. Rapid voltage changes are captured based on steady voltage tolerance,
steady time, minimum compensation and minimum rate detected. When voltage
change exceeds dip or swell threshold, it is considered as Dip or Swell instead of
Rapid Voltage Change. The events list shows voltage step change and transient
time. The detailed events list shows maximum voltage change over nominal voltage.
Voltage change trend is shown in the following pictures:
Picture: Characteristics of a rapid voltage change