ABB RELION REX640 Technical Manual page 355

1MRS759142 F
Figure 212: Single-phase earth fault, phase A
In an example of the phasors in a two-phase short-circuit failure where the fault
is between the phases B and C, the angle difference is measured between the
polarizing quantity U
REX640
Technical Manual
and operating quantity I
AB
Protection functions
- I marked as φ.
B C
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