ABB Remote I/O RIO600 Installation And Commissioning Manual page 105

1MRS757488 H
RIO600
Installation and Commissioning Manual
I
A
U
A
U
CA
I
C
U U
C BC
GUID-6DA409C2-E9BE-4A53-A5D3-38342B0D2352 V1 EN
Figure 55: Single-phase earth-fault of phase A
Figure 55 shows phasors in single-phase earth-fault, where the faulted phase is phase
A. The angle difference between the polarizing quantity U
I is marked as ϕ. Note that the polarizing quantity is rotated with 90°. The
A
Characteristic angle is assumed to be 0°.
Figure 56 shows phasors in two-phase short circuit failure, where the fault is between
phase B and phase C. The angle difference between the polarizing quantity
U U
and operating quantity
−
CA AB
Figure 55
U
AB
I
B
j
90°
U
B
I I
is marked as ϕ.
−
B C
and Figure 56 are valid if the phase rotation is ABC.
Section 6
Commissioning
and operating quantity
BC
97