Over Fluxing Detector (81Hlb5); Figure 5.8-1 Logic Diagram: Over Fluxing Detector (81Hlb5) - Siemens Argus 7SR21 Technical Manual

5.8

Over Fluxing Detector (81HLB5)

Over fluxing detector elements monitor the line currents.
The inrush restraint detector can be used to block the operation of selected elements during transformer
magnetising inrush conditions.
The 81HBL5 Bias setting allows the user to select between Phase, Sum and Cross methods of measurement:
Phase Each phase is inhibited separately
Sum The inrush current from each phase is summated and compared to each operate current
individually
Cross All phases are inhibited when any phase detects an inrush condition
An output is given where the measured fifth harmonic component content is above the 81HBL5 setting.

Figure 5.8-1 Logic Diagram: Over Fluxing Detector (81HLB5)

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7SR210 & 7SR220 Description of Operation
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