ABB Remote I/O RIO600 - Page 105

U
A
U
B
U
C
U
BC
U
AB
U
CA
I
A
I
B
I
C
j
90°
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
BC
and operating quantity
I
A
is marked as ϕ. Note that the polarizing quantity is rotated with 90°. The
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
CA AB
−
and operating quantity
I I
B C
−
is marked as ϕ.
Figure 55 and Figure 56 are valid if the phase rotation is ABC.
1MRS757488 H Section 6
Commissioning
RIO600 97
Installation and Commissioning Manual