ABB Relion Technical Manual page 234

Section 8
Current protection
228
ANSI06000650 V2 EN
Figure 102: Characteristic with ROADir restriction
The function indicates forward/reverse direction to the fault. Reverse direction is defined
as 3I ·cos (φ + 180°) ≥ the set value.
0
It is also possible to tilt the characteristic to compensate for current transformer angle error
with a setting RCAComp as shown in the figure 103:
3I Operate area
0
-3V
3I cos
0
ROA
1MRK 502 048-UUS A
=-
=V RCA = 0°
V 3V
ref o
0 ref
ANSI06000650-2-
vsd
en06000650_ansi.vsd
Technical manual